Technology Assessment Report - AMTonline

Technology Assessment Report

on

Current Global Advanced Research Projects in Fixed Abrasive Grinding

January 2005

AMT – The Association for Manufacturing Technology

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A Report Compiled and Prepared

by

Dr. John A. Webster, President Cool-Grind Technologies

673 Chaffeeville Road Storrs, CT 06268, USA

http://www.cool-grind.com [email protected]

for

AMT – The Association for Manufacturing Technology

Published by: AMT – The Association for Manufacturing Technology 7901 Westpark Drive, McLean, VA 22102 Printed in the United States of America Copyright © 2005 AMT – The Association for Manufacturing Technology all rights reserved. No part of this publication may be reproduced in any form, in an electronic retrieval system or otherwise, without prior written permission of the publisher.

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Preface............................................................................................................................................. 6

1. Introduction to Grinding ..................................................................................................... 7 1.1. Definition .................................................................................................................... 7 1.2. Modes of Grinding...................................................................................................... 7 1.3. Where is Grinding Positioned as a Finishing Process ................................................ 7 1.4. Future of Grinding ...................................................................................................... 8

2. Grinding as an Input-Output process .................................................................................. 9 2.1. The Process Inputs ...................................................................................................... 9 2.2. The Grinding Process.................................................................................................. 9

2.2.1. Grinding Interactions .......................................................................................... 9 2.2.2. Process Stability.................................................................................................. 9

2.3. The Process Outputs ................................................................................................. 10 3. Review of Fixed Abrasive Grinding Around the World................................................... 10

3.1. Workpiece Materials................................................................................................. 10 3.1.1. Ceramics ........................................................................................................... 10 3.1.3. Glass.................................................................................................................. 11 3.1.4. Tungsten Carbide and Powder Metals .............................................................. 11 3.1.5. High-temperature Gas Turbine Materials ......................................................... 12 3.1.6. Super-abrasive Materials (CBN and Diamond) [G54, IN1, C23] .................... 12 3.1.7. Silicon/AlTiC Electronic Materials .................................................................. 12 3.1.8. Ductile Materials............................................................................................... 13 3.1.9. Stone and Concrete ........................................................................................... 13 3.1.10. Fiber-reinforced Ceramics and Composites...................................................... 13 3.1.11. Ferrous .............................................................................................................. 13

3.2. Externally Assisted Grinding Processes ................................................................... 14 3.2.1. Electro-discharge .............................................................................................. 14 3.2.2. Electrolytic........................................................................................................ 14 3.2.3. Vibration-assisted [G10, G38, J1, J12, U9, U12, U13, U14, G74] .................. 15 3.2.4. Thermally assisted ............................................................................................ 15 3.2.5. Electro-chemica ................................................................................................ 15 3.2.6. Particle assisted................................................................................................. 16 3.2.7. Chemo-mechanica............................................................................................. 16 3.2.8. Combinations of above ..................................................................................... 16

3.3. Fluid Application ...................................................................................................... 17 3.3.1. Traditional Fluid Application ........................................................................... 17 3.3.2. Fluid Type and Evaluation................................................................................ 17 3.3.3. Reduced Flowrate Lubrication.......................................................................... 18 3.3.4. Nozzle design.................................................................................................... 21 3.3.5. Optimization of Flowrate/Pressure ................................................................... 22

3.4. Grinding Machine Design and Characteristics [GB34, C28, GB26, G66, SP2] ...... 22 3.4.1. Control Architecture ......................................................................................... 23 3.4.2. Slides/Servos/Positioning ................................................................................. 23 3.4.3. Spindles............................................................................................................. 24 3.4.4. Subsystems........................................................................................................ 24 3.4.5. Combined Grinding and Other Process ............................................................ 24

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3.4.6. Controlled Kinematics ...................................................................................... 25 3.4.7. Dynamic Response Characteristics of Wheel-work ......................................... 27 3.4.8. Static Stiffness .................................................................................................. 28

3.5. Abrasive Grinding Tools........................................................................................... 28 3.5.1. Tool Developments........................................................................................... 28 3.5.2. Testing of Tools ................................................................................................ 41 3.5.3. Engineered Abrasive Patterns ........................................................................... 43

3.6. High Speed Grinding ................................................................................................ 44 3.6.1. High Wheel Speed ............................................................................................ 44 3.6.2. High Work Speed.............................................................................................. 46 3.6.3. High Removal Rate........................................................................................... 47

3.7. Analysis, Simulation and Modeling.......................................................................... 49 3.7.1. Analysis of Empirical Data............................................................................... 49 3.7.2. Inductively Derived Models ............................................................................. 49 3.7.3. Deductively Derived Models ............................................................................ 51

3.8. Control of Grinding................................................................................................... 53 3.8.1. Artificial Intelligence........................................................................................ 54 3.8.2. Sensor-feedback with Constraint ...................................................................... 56

3.9. In-process Monitoring and Post-process Measurement Techniques [GB20, GB21, SP7] 57

3.9.1. Acoustic Emission and Audible Sound............................................................. 57 3.9.2. Force ................................................................................................................. 58 3.9.3. Spindle Power ................................................................................................... 58 3.9.4. Temperature ...................................................................................................... 59 3.9.5. Wheel Wear ...................................................................................................... 59 3.9.6. Workpiece Size ................................................................................................. 60 3.9.7. Vibration ........................................................................................................... 60 3.9.8. Displacement..................................................................................................... 60 3.9.9. Remote Monitoring........................................................................................... 61

3.10. Stability of Grinding [G12, G21, G43, G50, SP1, C32, U56, J46] ...................... 63 3.10.1. Vibration and Chatter........................................................................................ 63 3.10.2. Lobing ............................................................................................................... 64 3.10.3. Loading of Wheel Surface ................................................................................ 65 3.10.4. Stiffness Limitation........................................................................................... 66

3.11. Quality of Grinding Output [GB28, G59, G75].................................................... 67 3.11.1. Surface integrity................................................................................................ 67 3.11.2. Surface Finish ................................................................................................... 68 3.11.3. Burr Formation and Edge Chipping.................................................................. 69 3.11.4. Shape and Form ................................................................................................ 69 3.11.5. SEM, AFM, TEM Observations ....................................................................... 69

3.12. Truing and Dressing.............................................................................................. 70 3.12.1. Conventional Setups ......................................................................................... 70 3.12.2. Externally-Assisted ........................................................................................... 70 3.12.3. Unique Configurations...................................................................................... 72

3.13. Ultra-precision Grinding [A2, A12, C2, C11, C12, C15, C22, J19, J31, J34, K2, K4, T1, U10, U20, U42, C32, GB20, GB21, GB25, GB28, G74, J37, J38, U47] ............... 73

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3.14. Economic and Environment Drivers..................................................................... 74 3.14.1. Economically Driven ........................................................................................ 74 3.14.2. Environmentally Driven.................................................................................... 75

3.15. Optimization and Grindability Assessment .......................................................... 76 3.15.1. Design of Experiments...................................................................................... 76 3.15.2. Repetitive Grinding to Find Optimum.............................................................. 76

4. Conclusions....................................................................................................................... 76 5. References Cited and Further Reading Suggestions......................................................... 77 5.1. Additional References used in this Report.................................................................... 77

5.2. Useful Books............................................................................................................. 79 5.3. Useful Journals and Transactions obtained from Summaries................................... 79

6. Background of the Author ................................................................................................ 81 7. Acknowledgements........................................................................................................... 81

AUSTRALIA................................................................................................................ 83 AUSTRIA ..................................................................................................................... 99 BELGIUM .................................................................................................................. 101 BRAZIL ...................................................................................................................... 104 CANADA ................................................................................................................... 124 CHINA........................................................................................................................ 131 CZECH REPUBLIC ................................................................................................... 179 GREAT BRITAIN...................................................................................................... 185 GERMANY ................................................................................................................ 231 GREECE..................................................................................................................... 314 HOLLAND ................................................................................................................. 317 HONG KONG ............................................................................................................ 320 INDIA ......................................................................................................................... 324 IRELAND................................................................................................................... 330 ITALY......................................................................................................................... 333 JAPAN ........................................................................................................................ 338 KOREA....................................................................................................................... 390 POLAND .................................................................................................................... 398 RUSSIA ...................................................................................................................... 404 SINGAPORE .............................................................................................................. 409 SLOVENIA................................................................................................................. 412 SPAIN......................................................................................................................... 417 SWEDEN.................................................................................................................... 425 SWITZERLAND ........................................................................................................ 428 TAIWAN .................................................................................................................... 431 TURKEY .................................................................................................................... 433 UKRAINE................................................................................................................... 436 USA............................................................................................................................. 438

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Preface The following report was based on the use of a one-page summary format obtained from researchers that were contacted by email and telephone, during a 2-month period. From these abstracts, key words (categories) were deduced that helped to structure the report by: materials ground: the fluid application used; grinding tool design examined, etc. These keywords have been used to structure the report, and the same text may appear in different sections when appropriate. The summaries are referenced in each section, using country code pre-fixed letters, and can also be found in the appendix, sorted by country. References which are not pre-fixed by country code letters are additional publications that clarify some of the statements, and are listed in Section 5.1. The summaries contain full contact details for the researcher, an abstract of the research topic, details of any key issues that arose during the research, and a list of recent publications for further reading. The author did not advocate the use of graphics within the one-page summary format due to the huge increase in file size for electronic distribution, and a reduction in the text description would also have resulted. In the case when there are no publications cited, the reason may be either that the project is too recent, or there is a proprietary nature to the work. In most cases, the researchers will generally be pleased to receive communication on the topic outside of the confidential aspects. Although the initial objective was to identify projects which have been active within the last 5 years, the majority of summaries show much more recent research. A total of 198 research institutions from 32 different countries were contact, after being identified from an extensive literature search. From these 198 institutions, 14 did not do fixed-abrasive grinding research and only 10 did not respond to the initial request and reminders. In many cases, multiple summaries were provided by institutions, with Aachen WZL the greatest number at 16. In fact, at 79 summaries, Germany also submitted the most project information for the report. The total number of summaries receive by the cut-off date was close to 360. This report can therefore be considered as an accurate account of the status of fixed-abrasive grinding research around the world. Dr. John A. Webster Cool-Grind Technologies January 2005

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1. Introduction to Grinding 1.1. Definition

Fixed abrasive grinding is a collective name for machining processes that uses hard abrasive particles to remove material from softer materials, commonly called workpieces. It is one of the oldest machining processes in the world, as natural gritty rock was used to sharpen tools and weapons. According to Malkin [1], nowadays, grinding is a major manufacturing process which accounts for approximately 20-25% of the total expenditure on machining operations in industrialized nations. Without grinding, precision bearings, computer hard drives, sharp cutting tools, are some of the products that would not be available in the form they are today.

1.2. Modes of Grinding There are many modes of fixed abrasive grinding, too many to list here. The basic modes are cylindrical and surface grinding, where accuracy levels of rough, precision, and ultra-precision can be met with the right combination of machine, tool, fluid, and process conditions. Text books are a useful reference for further information on grinding modes

1.3. Where is Grinding Positioned as a Finishing Process

Figure 1. Comparison of Manufacturing Processes (courtesy Saint Gobain)

Flame CuttingSnaggingSawingPlaning, ShapingDrillingChemical MillingEDMMillingBroachingReamingBoring, TurningBarrel FinishingElectrolytic Grind.Roller BurnishingGrindingHoningPolishingLappingSuper FinishingPolishing/FAVSSand CastingHot RollingForgingPerm. Mold CastingInvestment CastingExtrudingCold RollingDie Casting

Process Roughness (microinches)

Roughness (microns)

2000 32 1 0.016

50 0.20 0.018 0.0004average



Roughness (microns)

2000 32 1 0.016

50 0.20 0.018 0.0004average



Roughness (microns)

2000 32 1 0.016

50 0.20 0.018 0.0004average

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Figure 1 shows fixed abrasive grinding to be at the precision side of standard manufacturing processes, with surface roughness Ra values in the order of one nanometer possible for the Fixed Abrasive Vertical Spindle setup. Chemo-mechanical polishing, standard polishing, lapping, single-point diamond turning and magneto-rheological finishing can all reach higher levels of surface finish than grinding, under the best conditions.

1.4. Future of Grinding In 1983, Norio Taniguchi published a famous chart showing machining accuracy capability versus time, for several precision processes. Although his prediction stops at the year 2000, the trend continues. The chart is shown in Figure 2.

1940 1960 1980 2000

100 (0.1mm)

10

1 (1µm)

0.1

0.01

0.001 (1nm)

0.3 nm Atomic Lattice

0.0001 (1Å)

Machining accuracy capability (µm

)

Ultra Precision Machining

Precision Machining

Normal Machining

Turning and milling machines Grinding machines CNC machines Lapping and honing machines Jig boring & grinding machines Step and repeat cameras Optical lens grinding machines Precision grinding machines Super-finishing machines Diamond grinding machines High precision mask aligners Ultra precision diamond turning machines Diffraction grating ruling engines Free abrasive machining Electron beam lithography Soft X ray lithography Ion beam machining STM/AFM molecular manipulation

Taniguchi Figure 2. Taniguchi’s Machining Accuracy Trend Chart

The future of grinding depends on competing technologies. For example, hard turning is encroaching on the precision and surface integrity of grinding, with often better economics, at the micron level of Ra values. However, grinding is moving more into the ultra-precision domain to keep ahead, even with relatively standard grinding machines. Stephenson [GB22] has recently produced the best ever reported surface finish (2.3nm Ra compared to 30nm Ra) on directly ground hard steels and bi-metallics, produced at stock removal rates typically one order of magnitude higher than previously published. The need to use ultra-fine abrasive grits (typically <1 um) and small depth of cut (at the micron or sub-micron level) to achieve nanometre surface finish has been shown to be unnecessary if a dynamically stiff machine tool is used. The current work has used 75 μm CBN grits and depths of cut up to 500μm on a Tetraform machine. However he has also done some grinding of glass (BK7) on a High Efficiency Deep Grinding Machine with resin-bond, electrolytically dressed, diamond wheels,

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and achieved around 5nm Ra. Although form accuracy generated on such a machine is not what you would call ultra-high precision, the surface finish value is impressive.

2. Grinding as an Input-Output process Grinding can be considered as an input-output process. Below are listed the inputs to the process, what happens during the process, and what are the outputs of the process. These terms will be used elsewhere in the report, so a brief introduction here may clarify the process.

2.1. The Process Inputs In order to grind a specific material to the required form and quality, a suitable machine tool is required with the necessary range of feeds and speeds, suitable static and dynamic stiffness, and can be positioned to the required accuracy. The abrasive tool must be chosen based on compatibility with the machine tool, the economics and batch size being produced, the type of truing/dressing system available, and the material being ground. To reduce the temperatures in the grinding zone and to lubricate the wheel and flush the chips away, a suitable grinding fluid and delivery system are required. Process conditions, such as: optimum infeed rates; infeed switching points; wheel and work surface speeds; and truing/dressing conditions; must also be set.

2.2. The Grinding Process

2.2.1. Grinding Interactions During the grinding process, several interactions take place between: the grain and the work; the bond and the work, and the chip and the bond. The interaction between the grain and the work is the desired chip removal process, with some degree of rubbing and plowing. The interaction between the chip and bond results in friction and bond erosion. Interaction between the bond and work also results in undesirable friction. If the wheel is optimized to the process, the interactions will be predominantly chip removal, with sufficient bond erosion to maintain chip space, and a low specific grinding energy will result. 2.2.2. Process Stability Chatter vibration, lobing (or waviness), deflection, and wheel loading, can all be considered as instabilities of the process. • Chatter vibration will results in marking of the workpiece and uneven wheel wear,

requiring frequent wheel dressing to compensate for it. • Lobing (or waviness) is a geometric error (out-of-roundness) on the workpiece that

may compromise the function of the workpiece. • Deflection of the wheel-work system leads to size error and longer cycle time to

relax the system. • Loading of the grinding wheel with workpiece material can occur if the material is

very ductile, the chip produced is long and curly, there is insufficient chip space between the abrasive grits, the grinding forces are higher than normal, and the fluid has poor lubricity. Wheel loading increases the grinding force and can lead to surface finish and surface integrity issues.

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• There can also be other forms of instability in the grinding process, such as film-boiling and local expansion of hot spots.

2.2.3. Heat Generation. The heat and temperatures experienced in the grinding zone are a function of the sharpness of the grain, the properties of the work material, the effectiveness of the fluid, the chip space available, and the chip thickness produced.

2.3. The Process Outputs The process outputs can be considered as: the final geometry; surface finish; surface integrity; tolerances; cost; and environmental impact. The input output system is shown schematically in Figure 3.

Figure 3. Grinding as an Input/Output System 3. Review of Fixed Abrasive Grinding Around the World The use of keywords to structure the report was felt to be the easiest way to link the data received and to allow for future updating with new summaries, if required. The format also allows for easier statistical analysis of the data by the author, for presentation at a future AMT meeting.

3.1. Workpiece Materials General categories of materials are listed in this section. A more detailed description of the materials will be available from either the summary or the full paper of the work. In many summaries the material type was not available or relevant, especially in the case of modeling and simulation work.

3.1.1. Ceramics: [A8, A3, A11, CA4, G2, G10, G38, P3, C4, C6, C12, C13, C16, C17, C20, CZ1, G35, IN2, IN3, IN4, J3, J18, J21, J20, J22, U9, U14, U16,U30, U31, U32, U33, U39, U40, U41, U42, C38, CZ5, C27, C32, G57, G58, G72, G79, J37, J44, SD2, U50, U53, U54]

Ceramics materials are the most popular test materials, after the ferrous group. Ceramics include silicon nitride, silicon carbide, alumina, zirconia, etc, with pressure-less, hot-pressing, hot-isostatic pressing, slip-casting, reaction bonding, etc. The critical issues when grinding ceramics is surface finish, surface damage, sub-surface damage, fatigue life reduction, and economical material removal rates when attempting to operate in the ductile removal regime.

Inputs

• Machine tool

• Work material

• Abrasive tool

ooling fluid

• ycle parameters

ruing/dressing conditions

• C

C

• T

Process

• Grinding interactions

• Process stability

• Heat generation

Outputs

• Final geometry

• Surface finish

• Surface integrity

• Tolerances

• Cost

• Environmental impact

Inputs Outputs

• Machine tool

• Work material

brasive tool

ooling fluid

• ycle parameters

ruing/dressing conditions

• Final geometry

• Surface finish

• Surface integrity

• Tolerances

• Cost

• Environmental impact

Process

• Grinding interactions

• Process stability

• Heat generation

• A

• C

C

• T

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Applications for ceramic components are numerous, i.e. water faucet valves, however the use of ceramics for structural components is growing and includes engine valves, fuel injectors and pump pistons. In such applications, good surface finish and surface integrity are paramount for long life when replacing traditional metal components. The grinding of ceramic coatings can also be a challenge, with failure modes such as de-lamination and edge chipping occurring. These materials are used as thermal barrier coatings for gas turbine hot-end blades and vanes, and also wear resistant surfaces. There has been some research on grinding nano-structured coatings with ultra-fine grain structure [U31], as well as with conventional ceramic coatings that are deposited by thermal spray and high-velocity oxy-fuel methods. 3.1.2. Metal Matrix Composites: [IT1] Only one summary was obtained on the grinding of Metal Matrix Composites. The material in question is the aluminum-silicon carbide material being developed for brake rotors. Although there have been encouraging results using single-point turning for this product, the tip wear due to the abrasive SiC particles requires frequent tool changes. The multi-point nature of diamond-wheel grinding may have better economics. Such tests are possibly restricted to private industry research institutions at this time. 3.1.3. Glass: [A2, CA3, C11, C12, C19, C22, GB3, GB16, G14, G15, G16, J6, J10, J31,

K2, U42, GB20, GB25, J39, J47, K5] Glass grinding generally encompasses the shaping and polishing of spherical and aspherical optical components to specula finish levels of quality. As with ceramic materials, glass is also ground in the ductile regime for best surface integrity, however there is often some brittle regime grinding (using larger grit size) to form the rough shape, followed by decreasing grit size operations to achieve final size. Some researchers have correlated damage depth to grit size, with final operations being achieved in the ductile regime after the previously damaged layer has been removed. In lens grinding applications, abrasive wear can be critical, especially with large components, since the disturbance of a dressing operation part way through the cycle is not desirable. For this reason, the ELID dressing technology [J31], described in the following chapter, is so successful for producing a mirror-finish. The use of compliant fixed-abrasive tools has also proved successful in achieving close to mirror-finish Some work is also being done on optic fiber end polishing to minimize attenuation at couplings and maximize transmission distance and bandwidth [C19]. 3.1.4. Tungsten Carbide and Powder Metals [A12, CA2, C5, C15, G31, J34, G63, G64,

G67, G69, G73, J37, J38, SD2, U51] Tungsten carbide is primarily used as a cutting tool material, however, other significant uses for the material include: long-life mold dies and inserts; and precision mirrors. Diamond grinding wheels are generally used to grind and sharpen the material, which

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presents the difficulty of truing using conventional techniques. Novel, externally-assisted, truing and dressing techniques will be described later on in the report. 3.1.5. High-temperature Gas Turbine Materials [C14, GB5, GB6, GB7, GB8, GB10,

GB12, GB13, G3, G5, G39, G48, G53, J5, J32, R1, R4, U3, U4, U28, U29, U44, C34, G68, J43, SP4, U56, CA6]

This group of materials includes the ductile alloys based on nickel, titanium, and intermetallics such as gamma titanium-aluminide, which are more brittle. The materials can be either: isotropic or directionally solidified; polycrystalline; or single-crystal. The critical issues that exist when grinding such materials are the reduction in surface integrity that occurs due to the high grinding temperatures. The materials have extremely low values of thermal conductivity and diffusivity, as compared to steels. These properties prevent the heat from escaping from the grinding zone through the bulk of the material, relying solely on the grinding fluid, or the chip, to remove it [U3][2]. The materials are also regarded as being abrasive to the wheel grain, and far lower G-ratios are produced as compared to hard steel materials.

The use of diamond and CBN grinding wheels, which have high thermal conductivity, is generally the preferred approach to grinding these materials [U29]. However, the economics of grinding versus machining, is a strong debate by gas turbine manufacturers, especially with titanium [GB5]. The use of high wheel speed [G5], electro-chemical assistance [GB8], speed-stroke [G48] and High Efficiency Deep Grinding (HEDG) [GB19] are currently being explored to address these economics. The more common continuous-dress creep feed (CDCF) grinding is popular for nickel alloy grinding, with a lot of recent advanced in cycle design and wheel cleaning, that is giving shorter cycle times and reduced wheel wear [U28]. In addition, recent research into robot grinding of turbine blades yields the possibility of replacing lines of workers who de-flash castings, with a single robot working 24 hours a day, without health related issues such as white finger [J5, BE1, U56].

3.1.6. Super-abrasive Materials (CBN and Diamond) [G54, IN1, C23] As well as being superb grinding wheel abrasives, diamond and CBN are also excellent cutting tool materials when formed into polycrystalline form, using binders such as cobalt. The difficulty comes when trying to grind accurate cutting edges using the same material in a grinding wheel. In some cases it has been reported that grinding PCD inserts with resin-bond diamond wheels, can yield G-ratios of less than 0.01, whereas grinding tungsten carbide can yield a ratio of 100 (10,000 times different). Loss of form of the grinding wheel can also be a big problem when trying to hold tight tolerances. Systems have been developed to aid the grinding process using electrical and chemical assistance, and these methods will be discussed in a later section. 3.1.7. Silicon/AlTiC Electronic Materials [A3, C1, C2, IR1, J7, J8, J11, J12, J29, J30,

J31, J35, T1, U8, U10, J36, J40, J46] Silicon is another brittle material that has to be ground in the ductile regime to avoid surface and sub-surface damage. Silicon is subject to ductile flow when the strain is restrained within 0.02%-0.03% [J7]. Fixed diamond abrasive wheels are traditionally used to planarize silicon wafers after sawing, with a subsequent polishing operation to

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remove the sub-surface damage. After formation of the microcircuits on the polished and etched surface, the backside of the wafer is also ground and polished before dicing of the individual circuits. Dicing of silicon ingots is generally achieved using ID saws with stressed cutting discs (like drum skins) to give an accurate, straight cut, however these saws cut one wafer at a time. These machines are being replaced by loose-abrasive wire saws that can cut many wafers at a time, albeit slower per single cut than the ID saw. A third method being researched and introduced is the fixed-abrasive wire saw, with far higher cut rate than the loose abrasive, with the same advantage of many wafers being created simultaneously [J11, J30]. The bonding of the diamond abrasive to the wire will be discussed later. 3.1.8. Ductile Materials [A8, J9, J40] In the context of this report, ductile materials means soft metals, such as unhardened steel, aluminum, copper, etc. They usually form a longer chip, require greater specific grinding energy, are more prone to loading the grinding wheel surface, and more likely to re-adhere onto the parent surface, than hard materials. In order for grinding to compete with the machining of ductile metals, the use of non-stick grain coatings [3] and high-pressure wheel cleaning are being explored, in conjunction with open-structure wheels that can accommodate the long, curly chip. Single-layer bronze bond wheels have some success in this area due to their high ratio of grit exposure. 3.1.9. Stone and Concrete [C7, C8, C9, C10, IT3, C24, C25] Construction materials, such as marble, granite, concrete, vitrified tiles and bricks, are often cut, shaped and polished by grinding. They can be hard to grind and easily damaged by the heat of the process. The diamond grinding wheels are often starved of coolant, and sometimes used dry, leading to a huge amount of dust generation and the associated environmental impact. In the case of marble and granite, they can be multiply sliced using ganged slitting wheels, or a linear frame saw with several blades. 3.1.10. Fiber-reinforced Ceramics and Composites [A6, G28, BE2] Few researchers are investigating the grinding of fiber reinforced materials. One researcher found that the direction of the fiber has a big influence on the sub-surface damage generated 3.1.11. Ferrous [ A1, A4, A5, A7, A9, B1, B3, B4, B6, B7, B8, B9, B12, C3, CZ3, GB1,

G4, G12, G13, G18, G19, G20, G21, G22, G25, G33, G34, G42, G44, G46, G49, G50, IT2, J17, J23, J28, K1, P2, R3, R4, SP1, SW1, SW2, TU1, U26, U27, U34, C30, C28, GB21, GB22, GB23, GB24, GB28, G60, G62, G70, J42, J43, SP6, U51, U52, U57, U58, CA5, CA6]

By far the most common materials being used for grinding research are from the ferrous family. These include steels, high-alloy steels and cast irons. They are very common materials in automotive and domestic appliances, with many of these manufacturers funding university research. Another reason for ferrous materials being common in research is their low cost and excellent grindability when the objective of the research is not based on the material itself, but verifying of a simulation model, or new grinding

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wheel design, is required. Ferrous materials are easily ground using inexpensive alumina/corundum abrasive, or CBN for superabrasive research.

3.2. Externally Assisted Grinding Processes In this context, externally-assisted grinding processes are those that are enhanced by electrical energy, dynamic motion, chemical activity or thermal input. The follow processes often overlap with externally assisted dressing techniques if the role of the assistance helps keep the grinding wheel sharp and clean from loading. Several externally-assisted grinding, or truing/dressing systems, have been developed in the last decade. The systems have been developed for diamond tool grinding, diamond wheel preparation, ceramic grinding, and others. The following acronyms describe a few of the electrically-assisted systems: • Electro-Chemical Discharge Machining (ECDM) • Contact Discharge Truing and Dressing (CDTD) • Electro-Contact Discharge Dressing (ECDD) • Electro-Discharge Machining and Grinding (EDMG) • Electrochemical in-process Controlled Dressing (ECD) • Electro-Discharge Diamond Grinding (EDDG) • Rotary Electro-Discharge Machining by grinding wheel (REDM) • Abrasive Electro-Discharge Grinding (AEDG) • Electrolytic In-process Dressing (ELID)

Some of the above systems will work with standard metal-bond superabrasive wheels, although in some cases, specially developed electrically-conductive bonds and coatings have been developed to enhance the process. A selection of these systems, identified by the one-page summaries covering recent work, are as follows:

3.2.1. Electro-discharge [IN2, IN4] Electro-Discharge Diamond Grinding (EDDG) has been developed for grinding PCD cutting tool inserts. The process has primarily been developed empirically up to now, however some modeling of the process is now being done, including FEM and parametric studies. The surface integrity of the tool material after EDDG is also being examined through FEM and experimental verification. 3.2.2. Electrolytic [C5, C12, G14, J31, GB29, GB21, GB22, U47] A variation of the ECDM technique is ELID [J31], where the grinding wheel is the anode and the electrolyte is supplied into the inter-electrode gap. The aim is to eliminate wheel loading and ensure permanent dressing. Using this technique on an ultra-stiff precision grinding machine, surface finish values of less than 10 nm Ra, have been achieved [GB21]. ELID usually employs a cast-iron fiber-bonded grinding wheel. An oxide layer (expensive rust) is produced on the wheel surface, during the electro-chemical reaction between bond and fluid, shedding worn diamond grains (see Fig 4). ELID enables the use

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of nano-order diamond grain sizes to be used, and can be applied to most modes of precision grinding.

+

Cast iron fiber bonded (CIFB) grinding wheel

coolant (electrolyte)

workpiece

source : Ohmori/Nakagawa, Japan

+-

electrode= cathode (copper, graphite)

grinding wheel (CIFB)= anode

brush

workpiece

coolant(electrolyte)

U

U

electrode= cathode

+-

outer diameter (OD) grinding rotation grinding

++

Cast iron fiber bonded (CIFB) grinding wheel

coolant (electrolyte)

workpiece

source : Ohmori/Nakagawa, Japan

+-

electrode= cathode (copper, graphite)

grinding wheel (CIFB)= anode

brush

workpiece

coolant(electrolyte)

U

U

electrode= cathode

+-

outer diameter (OD) grinding rotation grinding

Figure 4. Principle of ELID [J31] 3.2.3. Vibration-assisted [G10, G38, J1, J12, U9, U12, U13, U14, G74] Ultrasonic Assisted Grinding has appeared during the last 5 years for the grinding of ceramics and other brittle materials, giving relatively high material removal rates and low process temperatures. Both empirical and kinematic simulation studies have been investigated, especially on damage depth, surface finish and chip-size distribution [U13, G10]. The process is said to change the nature of the removal behavior of ceramic grinding by leaving a smoothed-over appearance to the surface that is less prone to particle detachment and therefore is superior for tribo-mechanically loaded surfaces [G38]. UAG can also be used for precision grinding of small holes in ceramic materials, decreasing grinding forces by up to 70% and improving surface finish by up to 30%. In silicon dicing applications, UAG has also shown benefit, although the study is relatively young. Rotary Ultrasonic Machining and Grinding (RUMG) combines the virtues of diamond grinding and ultrasonic machining, resulting in higher material removal rates and lower cost that some of the alternatives (EDM and laser-assisted) [U9]. A simple example of vibration assistance can be a segmented wheel giving rise to intermittent cutting action [U14]. 3.2.4. Thermally assisted [J3, U53] Experimental research has been done to fabricate electro-formed diamond tools which are used in conjunction with laser-assistance. The thermal softening of the otherwise brittle ceramic material aids chip removal and lowers grinding forces, as with EDM-G. 3.2.5. Electro-chemical [GB8, SD2] Titanium poses difficulties for conventional manufacturing owing to its low thermal conductivity, which can cause high thermal tool loads, and its high reaction affinity with atmospheric oxygen. An alternative technique, Electro-Chemical Grinding ECG, has been developed, in which mechanical and electro-chemical removal mechanisms occur [GB8]. Optimization of the process to secure appropriate machining variables for acceptable surface quality and rate of metal removal has been carried out, and also the

15

development of artificial intelligence techniques for a knowledge-based system arising from these results. The electrical conductivity of the grinding wheel, from arbor to abrasive, is critical to the process. 3.2.6. Particle assisted [J10] The combination of grinding in the presence of a slurry is not new, however, recent work has been done using an alumina fiber brush and peach powder slurry for the polishing of mirrors. 3.2.7. Chemo-mechanical [J8, C7, J36, J40] Although it is likely that Chemo-mechanical polishing will be the topic of a separate Technology Assessment, chemo-mechanical grinding is also being developed, which uses fixed abrasives instead of loose abrasive. 3.2.8. Combinations of above [CA2, SD2] ECDM combines ECM and EDM. The ECM action is assisted by the thermal erosive effects of the discharges. The grinding wheel must have a conducting metal bond, preferably bronze or copper. The ECM and EDM time periods need to be balanced. In the first stage ECM occurs and anodic dissolution of the outer layer of the workpiece takes place. In parallel, mechanical grinding also occurs. On increasing the voltage in the second stage of the process, the concentration of the ions increases until electrical discharges occur. A plasma channel is created and material removed by evaporation. The technique has also been applied to truing and dressing of grinding wheels [SD2], which are then used for high precision grinding of cylindrical workpieces. Grinding wheel surface quality and roundness error are claimed to be superior to those obtained by conventional grinding.

Workpiece

metal bond wheel

vf

abrasive

Workpiece

metal bond wheel

vf

abrasive

Figure 5. Principle of EDM-G (CA2) Electro-Discharge Machining-Grinding is a hybrid machining process that integrates EDM with grinding [CA2]. The electrical spark discharges in the grinding zone, thermally softening the work material and reducing the grinding forces. The method is also very effective in preventing the wheel from loading during grinding. A suitable workpiece material would also be poly-crystalline diamond (PCD).

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3.3. Fluid Application Coolant application is possibly the last part of a grinding system that is considered by a process engineer. Often a machine tool is fitted with crushed pipes just days before customer run-off, with tweaking done to the aim and aperture during the trials. The investment made in nozzles and pipework is much less than on grinding wheels, dressing systems and orders of magnitude less than the machine, however improper coolant application can severely limit the potential of the process. The following sections describe the use of conventional coolant set-ups, fluid evaluation studies, reduced flowrate environmental approaches, nozzle design and optimization studies.

3.3.1. Traditional Fluid Application [B1, B6, B8, B11, CZ3, GB4, GB5, GB7, G9, J13, J32, K1, P3, R1, TU1, TU2, G59, G71, J41, SP4, U50]

The term ‘traditional’ relates to the use of low pressure pumps, crush or low precision nozzles, turbulent flow conditions and non-optimized flowrate/pressure. In many cases the fluid conditions are not known to the researcher, except for an approximate pressure and flowrate, based on the pumps’ documented characteristics rather than actual measurements. The author has seen huge pressure drops (90%) from the pump to the nozzle, due to bends and restrictions. In the case of grinding tests where fluid pressure is a variable condition, the test can be invalid if the same nozzle is used for each test, as the flowrate will also increase with pressure. The true way to do such a test is to fit different nozzle apertures to create the same flowrate at different pressures. If the objective of the test is to vary the flowrate through the same nozzle, then the same concern occurs with the resulting pressure change. The references attributed to this section are those of researchers that state that they use coolant application but do not infer much knowledge about optimizing the conditions they use. In some cases, the researchers are comparing traditional application with reduced quantity approaches, especially with respect to the surface integrity, surface finish, grinding zone temperature, wheel wear and process forces/power. If the traditional set-up has not been optimized the comparison may not be valid. High-porosity grinding wheels are designed to transport greater quantities of fluid through the grinding zone [R1]. Maintaining sufficient structural strength at high levels of porosity can be difficult to achieve. In the case of creep-feed grinding wheels, the structural strength does not have to be as high as in shallow-cut grinding, as the contact area is large and unit stress much lower. The use of continuous dress also enforces a wheel wear rate greater than the natural wear rate. 3.3.2. Fluid Type and Evaluation [B5, B6, B8, B11, B14, C3, C7, C16, G2, G40, U12,

U38, SP5, U51] Traditionally, grinding fluids fall into the following categories: emulsions, semi-synthetics, fully synthetics, and straight mineral oils (without the addition of water). The properties and chemistry of the fluids dictate their lubricity, cooling ability, microbial resistance, corrosive effect, drag-out loss, wheel loading resistance, filterability, working life, and disposal cost. Recent developments in biodegradable fluids [B11] have reached a

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stage where they can compete with traditional fluids, but without some of the drawbacks. The most environmentally friendly fluid is pure water, which is often used in silicon wafer grinding, to eliminate the potential for contamination. Dental grinding wheel research must also use water as a medium when being compared to carbide burrs [C16]. Many researchers have compared different fluids types, and a standard test procedure has been developed by TechSolve, Cincinnati, Ohio, to evaluate new fluids in comparison to their database. Their website is: www.techsolve.org. The reduced flowrate methods, to be described in the next section, often require newly developed fluids to operate effectively, and may not require some of the attributes of a fluid designed for relatively high flowrates, such as, anti-foaming, bio-resistance, etc. 3.3.3. Reduced Flowrate Lubrication [B14, G24, G66, G75, J41, K5, SP5][4] The term ‘reduced flowrate’ is a relative term. Traditional grinding uses ‘optimum’ flowrate models of 25GPM per inch width of grind (4 liter/min.mm), or 2 GPM per grinding horsepower (10 liters/min.kW) [4]. The fluid serves the function of providing lubrication, cleaning the wheel, cooling the part, thermally stabilizing the machine structure, and flushing the chips from the machine bed. By comparison, the term Minimum Quantity Lubrication (MQL) can mean much less than 1 GPH is injected into the grinding zone. The reduced flowrate approach is usually based on environmental considerations rather than improved grinding performance. The cost benefits may not be due to the grinding performance, but be more associated with reduced ground contamination, less dragout, less bio-film and dermatitis issues, close to zero disposal cost, lower mist levels, higher value chip waste, reduced pumping and cooling energy, and less fluid maintenance staff. Even if the MQL systems reduced productivity by 50%, the economic and environmental benefits of the system may still offset the disadvantages. High pressures, and low flowrates has proved to be extremely successful in machining, however, the larger chip size and resulting lower specific cutting energy creates far lower residual surface temperatures than grinding. The challenge of grinding, with small chip thickness and undefined cutting edge geometry, will be a significant hurdle to overcome, unless the environmental case dominates.

3.3.3.1.MQL [A4, B1, B2, G30, G40, G42, G49, J17, K1, P3, U38, B16, GB24, G76] MQL is understood to be the application of a mist of lubricant into a high pressure air stream. The air is generally not cooled and fluid flowrates are extremely low. It has been stated that in MQL the cooling comes from the latent heat of vaporization of the fluid quenching the grinding energy. Once vaporized, the product has to be collected and condensed elsewhere, and not discharged back into the environment to be truly environmentally correct. The author feels that the greatest impact of MQL will not be due to direct substitution with existing high flowrate grinding processes, but with HEDG regimes where most of the grinding energy goes into the chip produced rather than the ground surface. In

18

HEDG, this desirable energy partitioning at high wheel speeds and table speeds, maintains acceptable part temperatures with little cooling effect required by the fluid [G42][2]. The lubrication aspect of the fluid with regards abrasive wear, may well be more important than the cooling effect in this regime. Contrary to the above statement, advocates of MQL have generally only used the technology for very small depths of cut [J17]. Grinding processes that are compromised by high hydrodynamic pressures, such as high contact area applications, will experience less push-off with MQL and may therefore require reduced sparkout times. 3.3.3.2.Cryogenic and Cool Air [A4, HK2, J13, J15, J17, J32, K1, TU1, C34, G59,

J43] The cooling ability of a gas or liquid depends on the temperature difference between the hot part and the gas or liquid, i.e. cold air can take away more heat than warm air. This effect has been exploited by researchers who may use either cooled air or liquid nitrogen, and with or without an oil lubricant. Since nitrogen is the most abundant gas in the atmosphere, it is unlikely to cause environmental problems. Cooled air is similarly benign and the method uses a refrigeration unit [HK2], vortex tube [K1], or liquid nitrogen supply [J13, G59] to reduce the air temperature. Even without air or gas, some researchers have cooled the grinding fluid to less than 320F (00C) to be able to conduct more heat away from the grinding zone [HK2]. The results were compared to room temperature fluids, showing significant benefits. Fu [C34] is investigating cryogenic pneumatic mist jet impinging cooling technology for grinding titanium alloy. 3.3.3.3.Dry [7] J13, J17, J32, P3, R2, TU1, TU2, GB24, G76, J43, J44, U51] Not surprisingly, no researchers reported any advantages of grinding dry, without using a cooled air supply. The finished surfaces were often covered with chips and a lot of sideflow (plowing) existed. A highly porous grinding wheel was reported to have created up to 4 times less workpiece heat than a conventional wheel, with up to 40 times the removal rate [R2]. It is likely that the porous structure acted like a radial flow pump and generated its’ own air supply. The greater chip space would form a larger chip, with associated reduction in specific grinding energy. 3.3.3.4. Water and Water-Air [IR2, C35, J43, J44] Torrance has been experimenting with air/water mists propelled at close to Mach 1 into the grinding zone. Multiple jets were recommended for best effect. The system is very inexpensive to set up and presents little environmental impact. The benefit from wheel cleaning appears to be significant. Fu [C35] has tested water jets at 110m/s in order to study the change in critical power flux and heat transfer for different conditions. 3.3.3.5. In-wheel Lubricants and Coatings [IN1, J40][3][5][6] The push towards minimum quantity fluid application and a reduction in fluid disposal costs, has encouraged researchers to examine the integration of lubricants

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into the structure of the grinding wheel. This has resulted in several patented designs, including: • Superabrasive segments impregnated with resin and proprietary solid lubricant • Sol-gel alumina grain in vitrified bond, filled with oil/wax mixture • Vitrified aluminium oxide wheels impregnated with water-insoluble, sulphur

bearing, organic substance

Salmon [3] used cutting tool coating technology on CBN grains to counter the boric oxide formation when water-based fluids are used. His two-step approach was to use a hard titanium aluminium nitride (TiAlN) coating on an electroplated grinding wheel, followed by a layer of molybdenum disulphide (MoS2) hard lubricant. Salmon’s tests on MAR nickel-based alloy showed that the coatings gave longer life, lower grinding power, and no grain capping, despite the absence of cleaning jets. Tang [6] also explored the use of MoS2 lubricant, but with titanium alloy workpieces and silicon carbide wheels. Tang found a reduction in grinding forces, lower specific grinding energy due to reduced ploughing and sliding, and less adhering of titanium on the SiC grains. Unlike Salmon, or Tang, the approach taken by Shaji [5] was based on a unique wheel design that incorporated a solid lubricant. The vitrified aluminium oxide wheel, shown in Figure 6, has dovetail slots on the periphery, filled with a phenolic resin-alumina-graphite mixture. Dry grinding tests on Rc60, EN31 bearing steel showed: better surface finish, lower spindle power, and higher wheel wear, as compared to wet grinding without the solid lubricant. The researcher attributed this to the interrupted cutting action promoting high forces on the leading edges, resulting in breakdown of the vitreous structure.

Figure 6. Graphite Impregnated Wheel [5]

In order to overcome the hydrodynamic problems associated with fluids in chemo-mechanical finishing of silicon wafers, Enomoto developed a grinding wheel with microcapsules of oil incorporated into its’ structure [J40]. Lee also had problems with

20

hydrodynamic pressure and aimed the fluid against the direction of the grinding wheel to reduced the film thickness [K5].

3.3.4. Nozzle design [A10, B1, B8, B12, G23, G24, S2, U38, GB30, GB19, GB23, SP6] Nozzle design is a very broad topic as the objectives of each designer are different. Some researchers require a coherent jet of fluid to target the grinding zone some distance away from bulky fixturing. Another designer may want to exploit the high porosity of a creep feed grinding wheel, and the shoe nozzle may be the best option. High-pressure cleaning jets have different geometries, and the jet may fan-out to cover a wide area. Adjustable nozzles may be required for MQL application where the minimum effective flow is sought. The coherent jet nozzle has been developed from firehose designs, where it is designed to fire a high flowrate jet of water into a 5th story window. The benefits of coherent jets has been proved by the author, in many applications, as a simple but effective tool to achieve high grinding performance [B12][7]. Since the jet is so coherent, it should ideally be positioned relative to the workpiece, not the wheelhead, to prevent misalignment as the grinding wheel diameter reduces (Figure 7)

Figure 7. Coherent Jet at 15 bar [GB19] Shoe nozzles force the grinding fluid into the wheel structure by wrapping around the wheel surface just ahead of the grinding zone, and can incorporate internal flowguides for best effect. Passive designs need to be adjusted as the wheel diameter reduces, which is less of an issue with superabrasive types [G23, S2, B12]. Active designs are self-compensating by seeking the wheel surface. However, large wheel diameter changes (new to stub size) are not easily accommodated by this design, as conformity to the change in curvature is only possible in a radial direction to the wheel, which is not a convenient location. Ninomiya’s design [8] uses a replaceable tip that is ground by the wheel to form a good seal. Such designs are also being used for superabrasive applications, where the diameter change is less severe.

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Megasonic nozzles [9][10] show promise since they use very low fluid flowrates for medium stock removal rates. Ultrasonic agitation of the fluid gives it greater energy, allowing it to travel a greater distance at much lower pressures and flowrates than coherent jet nozzles would need. 3.3.5. Optimization of Flowrate/Pressure [IR2, G40, G24, G23, G21, G18, G5, G3, B14,

B12, B8, B1, A11, A10, GB30, GB34, GB19, GB23, K5, SP6, SD1, U47] As stated earlier, there are several flowrate models for traditional fluid application, either based on grinding width or grinding power, or both [G23, G24]. Webster performed creep-feed grinding tests, using a wedge-shaped workpiece, and interrogated several flowrate models [4]. It has been shown by many researchers that the effective flow through the grinding zone is a fraction of the applied flowrate. In the case of resin-bond diamond wheels for grinding ceramics, Spur [11] showed only 5% of the applied flowrate was effective. In the case of creep-feed grinding wheels, Malkin [12] showed that more than 50% of the applied flowrate may be pumped by the wheel through the grinding arc. In applications where the effective flowrate is low, a more efficient application of a much lower flow rate should theoretically achieve the same grinding performance as a high flowrate applied poorly. Of course, the bulk cooling and flushing benefits of the ‘wasted’ flowrate are ignored by this statement. To achieve the desired flowrate, the nozzle aperture must be correct in order to create the required pressure inside the nozzle. The pressure requirement is usually based upon the common practice of matching the jet speed with the wheel speed. The pressure to achieve this match can be obtained through Bernoulli’s equation, based on fluid density, the nozzle efficiency and the required velocity. It has been shown that when the two velocities are matched, the maximum benefit is reached, providing that the flowrate is also optimum. It is speculated that the matched jet breaks through the air barrier that surrounds the wheel and has an undisturbed entry into the grinding zone [13][14].

Morgan [GB30] developed a model for estimating the flowrate between a rotating grinding wheel and a workpiece. It was found that the useful flow that passes through the contact zone is a function of the spindle power for fluid acceleration, wheel speed, and delivery nozzle jet velocity. Two loss coefficients having values less than 1 are required to be calibrated for the particular grinding wheel and fluid delivery type. The model is then valid for a range of delivery flowrates for the particular wheel and nozzle conditions. The model makes it possible to determine a suitable value of nozzle outlet gap to achieve a required fluid film thickness in the grinding zone. Morgan [GB30] is also developing a guide for optimization of the jet velocity in relation to the power required to accelerate the fluid and the particular velocity of the wheel. The model has been validated experimentally. Its’ simplicity and accuracy allow application to a wide range of practical grinding situations.

3.4. Grinding Machine Design and Characteristics [GB34, C28, GB26, G66, SP2] This section only includes grinding research that has an impact on the machine tool and may help to improve the machine tools of the future. It is not intended to cover grinding machine design, which would justify a Technology Assessment of its’ own.

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3.4.1. Control Architecture [B12, B13, C6, C11, G17, SL1, U1, U2, U5, U26, U35, U37] Open architecture control (OAC) systems are more robust than PCs but share some of the virtues with respect to ease of use, familiarity and low cost, i.e. the Windows operating system can be used. This control hardware technology has replaced a lot of the dedicated and inflexible CNC systems of the 80’s and 90’s. They can be fitted with Analog-Digital and Digital-Analog converters for measurement signal input and control output. OACs can also be connected to the internet to order new grinding wheels automatically, or report errors. The integration of Acoustic Emission sensors, for wheel/work contact, dresser/wheel contact, collision, and wheel surface mapping, into the OAC structure is being done by Oliviera [B12]. The system is being developed for crankshaft grinding, and integrates with the independent controller used for CNC chase-the-pin actuation of the wheelhead. 3.4.2. Slides/Servos/Positioning [SL1, J24, J7, J47, HK3, G53, G51, G31, G22, C17,

U28] The machine tool slideway position, velocity and acceleration values are now controlled through Programmable Multi-Axis Controllers (PMAC) [C6, C11], which communicate with the OAC. Adaptive control of crossfeed axis displacement in surface grinding can have a significant impact on the cycle time. Okuyama [J24] has developed a hydrophone acoustic sensor that detects the initial contact and end of contact between the wheel and the workpiece. Once the wheel has left the part, the table is instructed to reverse. The system can also be used to detect downfeed contact with the part. Guo [U28] also controls the cross slide position in CDCF grinding. He decelerates the wheel into the part at initial contact until steady state grinding occurs, then accelerates the wheel out of the part at the end of the cut, thus shortening the cycle time. Gao [HK3] has developed a composite control system that gives rapid approximate positioning, with trimming of the exact position done using slow actuating piezo-electric linear actuators (PZT). The system relies on accurate linear encoders to be sure of the true position. The Abbe offset between the wheel position and the measuring position will control the ultimate accuracy of the system. The manufacture of linear guides is being made easier by Brinksmeier [G22]. His team have successfully employed the grind-hardening method to rough-grind, surface-harden and finish-grind the rails in one setup, avoiding the distortion and increased cost through an intermittent heat treatment operation. Speed-stroke grinding is a surface grinding process where the acceleration (up to 50g) and velocity of the worktable are very high (650 fpm, or 200m/min), in order to create high material removal rates and low thermal damage [G53]. High-power linear motors are expensive but the obvious choice for a linear velocity profile, however rotary motors and 4-bar linkages [C17] have been used as well, but will be subject to a sinusoidal velocity profile. Mass damping and counter-balancers are required to reduce seismic

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vibration which will require additional off-time before the table settles and can be confidently reversed. At IFW [G72], the development of automated grinding of free form surfaces of low-wear ceramic implants (consider knee joints as an example) is promoted with the aim of optimized lifetime. The basic mechanisms of five-axis grinding and polishing are analyzed and, based on this process and tool design, the development of a suitable manufacturing strategy take place. This technology will enable the fabrication of a variety of complex prostheses for medical technology, such as wrists and ankles. 3.4.3. Spindles [J12, S2, SL1, GB32, GB27, J41, SP4] Much university research has been done on generic machine tool spindle and motor design, however, designs specific to grinding are less common. Suwabe [J12] has developed a unique high-speed spindle system, with integral ultrasonic actuator, for the dicing of silicon wafers. In an effort to minimize the drag (and heat) associated with grease-packed and oil-mist lubricated rolling element bearing spindles, Yeo [S2] has developed a new method of mist lubrication that minimizes mist collision, has better tribological behavior, and better heat management. Suzuki has developed an ultra-precision air-bearing spindle for tungsten carbide micro-surface grinding applications, which rotates at a frequency of 150,000 rpm, and uses miniature grinding wheels to produce small lens molding dies [J37]. 3.4.4. Subsystems [U10, SL1, G51] In this report, ‘machine tool subsystems’ includes truing and dressing systems, workholding systems, load/unload mechanisms, etc. Pei [U10] is investigating the use of a soft pad beneath a silicon wafer, instead of a rigid chuck, as a more effective method of removing the wire-saw waviness during single-sided flat grinding. An active workblade has been developed by Klocke [G51] to improve the rounding mechanism in centerless grinding. The blade adjusts the vertical height of the workpiece above center to round up the odd number frequencies quickly, without creating new lobing frequencies before size is finalized. Chatter vibration avoidance may also be improved with the system. 3.4.5. Combined Grinding and Other Process [C22, G30, G46, H2, J3] In terms of precision, the least number of times a workpiece is fixtured and re-fixtured, the more precise the geometry of the individual features are (relative to each other). In the case of cylindrical grinding machines, the integration of OD and ID wheels on the same machine has resulted in better concentricity between internal and external surfaces. If machining and grinding were also integrated into the same machine, the machined and ground surfaces would also be very concentric, perpendicular or parallel. It is now common practice for machining centers to have grinding wheels in their tool-changers, and they have been fitted with greater spindle speed-ranges to take advantage of grinding

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wheels. There may be compromises made in fluid type since to avoid the space taken by a truing device on the machining center, electroplated superabrasive wheels are often use. Neat oil fluids yield far higher electroplated wheel life than water-based types, however electroplated wheels are often asked to run in the water-based fluid preferred for the machining operations. Guo [C22] is developing a prototype machine that can ultra-precision grind micro-aspheric lenses and magneto-rheological fluid polish them, on one machine. He uses locus optimization and error compensation to develop the process accuracy. Instead of comparing the economics of grinding versus hard turning, Weinert [G30] has exploited the virtues of each in his combined hard-turning and grinding machine. A two-step approach of roughing-by-turning and finishing-by-grinding, is used. The application of MQL for lubrication allows effective ID grinding to also be done. Klocke is combining three processes into the HHFlex machine [G46]: hard-turning; grinding; and hard-roller burnishing. Rough machining by hard-turning is followed by fine-finishing by grinding, with subsequent burnishing to improve the fatigue life through compressive surface stresses. Karpuschewski’s research focuses on the machining of small bores (2-6 mm in diameter) in hardened steel. He has developed a machine with two spindles that can hard drill the component, followed by internal grinding. The length-to-diameter ratio of the holes is a controlling factor in this operation [H2]. The application of heat to a ceramic material prior to grinding has also been studied. Senba [J3] used a laser within an ultraprecision grinding machine, to increase the grindability of the material. Marinescu [U53] has taken a similar approach on a conventional creep-feed surface grinder. 3.4.6. Controlled Kinematics [J28, J24, J6, J5, IR1, H1, G53, G48, G36, G26, G6, GB15,

C22, C17, C11, CA3, A2, A1, GB24, G58, G62, G64, G67, G68, G70, G72, G79, J37, J38, J47, U50, U57]

Chase-the-pin CNC crankshaft grinders can control the path of a grinding wheel to an accuracy of 1μm, with a throw of several inches, and a crankshaft rotational frequency of 3-4 Hz. The kinematics of such a machine are very complex with compensations for deflection built-in for greater precision. The variation in forces during such an operation have been studied by Hodgson [A1]. He produced a mathematical model based on system stiffness, complex geometrical relationships, and material removal rate. The force model was verified and deemed to be suitable for production applications. Fujiwara is using simulation for a similar application, cam grinding [J28]. Zhou [C30] is developing a simulation model for both cam and crank grinding. Koshy [CA3] is developing novel kinematics for the cylindrical traverse grinding of brittle materials. Since conventional cylindrical grinding machines produce a grinding lay pattern in the same plane as cracks would develop under bend testing, the flexural

25

strength would be reduced. With surface grinding brittle testpieces are often ground lengthwise to achieve the best flexural strength. With cylindrical grinding this is not an option. For this reason Koshy is designing a machine that produces lay marks in an axial direction to the part. Taking this approach he has achieved a 30% increase in flexural strength. It is well known that exact integer frequency ratios between the grinding wheel and a cylindrical workpiece, will generate the same number of integer waves on the surface of the workpiece if any forced vibration exists, especially wheel unbalance. In the late 70’s, Trmal and Kaliszer looked at this phenomena and ensured that they did not do cylindrical grinding studies at exact integer ratios. In the late 90’s, Trmal and Pearce developed a waveshift control strategy to ensure high levels of roundness. Waveshift is defined as a measure of the phase shift between the waviness produced on the workpiece in successive revolutions [GB15]. It is calculated as follows: The wheel rpm is divided by the work rpm. The resulting ratio is then subtracted from the next highest integer. The remainder is known as the waveshift and represents the way that waviness produced by wheel run-out overlaps from one workpiece revolution to the next. An exact integer ratio of rpm gives a waveshift of 0, in which the waviness over successive workpiece revolutions is in-phase. This leads to maximum values of roundness errors that are equal to the wheel run-out, regardless of the amount of spark-out. The overlapping effect from non-integer ratios reduces the roundness errors, particularly during spark-out. Weinert has looked at similar strategies with surface grinding, but has taken the approach of varying the grinding wheel frequency small amounts after leaving the work surface, to destroy any synchronization effect that could take place [G26]. The planetary motion of lapping machines produces relatively even platen wear and random lay marks on the workpiece surfaces. TUB have developed double-disc grinding machines with lapping kinematics, in order to get the same benefits with fixed abrasive wheels. More recent work has been on simulation work to predict the material removal mechanism and surface finish produced [G6]. Hoffmeister has developed self-adhesive diamond abrasive foils that replace conventional fixed abrasive wheels on these planetary grinders. They need no dressing and do not result in carrier disk wear [G58]. Although Karpuschewsky’s approach to profiling superabrasive wheels can be regarded as truing, it is also pertinent to include in the machine tool section. Profiling of diamond wheels is extremely difficult using conventional CNC truing disks, since the truer geometry does not remain constant if relative motion is created between both wheels and wear occurs. The new method perfectly synchronizes the truer to the wheel, using a feedback control loop. The operation is done at frequencies lower that used for grinding, but with the added precision of being done on the grinding machine instead of a separate truing station. The 100% crushing action that occurs with the system produces extremely accurate profiles. Denkener is using a similar approach, but is also developing traverse crushing, to generate wheel forms [G64, G67]. Industrial robots are versatile and tireless, but as compared to grinding machines they are much more compliant and also have lower positional resolution. As previously mentioned,

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robots can replace human beings in hand fettling and deburring operations if the control only requires positional feedback for consistent part geometry. For blending repair brazing on the airfoil surface of turbine blades without damaging the original surface, force feedback and measurement systems are necessary. This approach is being taken in Japan [J5], Belgium [BE1] and the US [U56]. 3.4.7. Dynamic Response Characteristics of Wheel-work [C21, GB17, G26, G35, G49,

G53, GB32, C30, G62] Modal analysis is an effective tool for analyzing the harmonic response and natural frequencies of a grinding machine. Pearce [GB17] measures the vibration characteristics of a grinding machine to identify speeds and feeds that may disturb the grinding process by causing chatter vibration. He is developing a stability boundary model that incorporates stiffness, mass and damping characteristics, in order to understand the modes and responses of the machine that should be avoided. The replacement of conventional abrasives by superabrasives has led to an increased tendency for regenerative chatter. According to Sexton [40] this is due to the increased contact stiffness of thin-rim CBN wheel design over a monolithic conventional abrasive wheel design. Aurich, et al, used the Finite Element Method (FEM) to optimise the dynamic behaviour of a diamond wheel for grinding ceramics. Using FEM analysis, they compared the synthetic resin aluminium composite to a solid aluminium disk. Using this data, they predicted the dynamic behaviour of both grinding wheel designs, and their influence on the material removal mechanism. Figure 8 shows the FEM analysis of the contact stiffness [G35].

synthetic resin alu-minum composite hub

aluminum hub

grinding wheel deformation relative tothe circumference of the rotating

grinding wheel non

contact elements simulatingsliding and penetration

nodal displacement(vector sum, aluminum hub wheel)

workpiece materialdepth of cutcutting speedfeed rate

::::

hot-pressed silicon nitridea = 1.5 mmv = 50 m/sv = 160 mm/min

ecw

dimensions : displacement1 : 400 µm

0123

circumference of the grinding wheelrotating

circumference of the grinding wheelrotating

4 µm

9.4 µm

F’ = F’ = 110 N/mmresultantn

F’ = 18 N/mm

t

b

a d

c

Figure 8. FEM analysis of contact stiffness [G35]

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3.4.8. Static Stiffness [U32, U31, U6, SL1, G49, G15, A1, G62, G74, J36] Conventional grinding machines may have a static stiffness of anywhere from 25,000 pounds/inch, to 3 million pounds/inch, depending on their design and physical size. A grinding machine with a static stiffness of 100,000 pounds/inch will deflect by 0.0001” with a normal grinding force of 10 pounds. If the instructed downfeed of the machine is 0.001” and a normal force of 10 pounds is generated, the true depth of cut will be 0.0009”. For this reason, researchers should quote true depth of cut in their results, not the instructed value. National Physical Laboratory, UK, developed an ultra- stiff grinding machine, known as the Tetraform. The design has been extensively tested by Cranfield and Bremen Universities [U15] and cited in many publications. Using such a machine for grinding tests on brittle materials, ensures that the measured grinding output is truly created by the grinding process and the data has not been distorted by the dynamic and static responses of the grinding machine. For this reason, Zhang [U32] investigated the effect of machine loop stiffness on the grinding of ceramics. He developed an adjustable stiffness workholding system and found that if the static stiffness is above a critical value, no chatter should occur in the grinding process. In contrast, if the stiffness fell below the critical value he got chatter. He used an extremely stiff grinding machine for his tests so that the static stiffness of the workholding system was dominant in the total stiffness value. Libo [J36] is developing a 3D analytical model, which incorporates tool stiffness and the infeed system, to study the influence of tool stiffness on the planarization process.

3.5. Abrasive Grinding Tools This section deals with research on fixed abrasive grinding tools, or where a special tool was developed to achieve a specific result.

3.5.1. Tool Developments Fixed abrasive products can be regarded as engineered composite materials, made of four elements: One or several abrasives: either conventional-fused (e.g. Al2O3, SiC or ZrO2 based);

conventional-sintered; or super -abrasives (e.g. cBN or diamond) A bond to hold or support the abrasive(s): resin or polymer based; vitrified or ceramic

based; or metal based, sometimes in a single-layer brazed or electroplated format. Some porosity and/or additives. Porosity is typically present to provide clearance for

the chips created during the grinding process, for fluid transport, and to enhance the various interactions taking place in the grinding zone. The porosity itself can either be natural or artificially induced. Various grinding aids, fillers and lubricants can be added.

Tool design, including the composite abrasive profile, abrasive thickness, hub material (if not a monolithic design), strength to withstand rotational stresses, precision and resistance to chemical attack, belt backing material, etc.

These four constituents are deployed by the abrasive product manufacturers to achieve the desired workpiece requirements (shape, finish, removal rate etc.). Abrasive

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manufacturers in turn tend to refer to their products as either: bonded abrasives (conventional grinding wheels), superabrasives, or coated abrasives (belts).

3.5.1.1.Grain [GB3, GB16, G44, G45, U25, G56, J39] The abrasive grain is the hard-phase component of a grinding tool and has the greatest influence on the output and viability of a grinding process. For example, the size of the grain has significant influence on the forces, power, wear rate, surface finish, etc. With respect to conventional grain materials, Sintered Sol-Gel aluminum oxide abrasives are the state-of-the art. They present significant advantages compared to their fused counterparts – particularly in term of life – and are much less expensive than superabrasives. When properly used, sintered abrasives can also result in significantly increased volumetric removal rates, reduced forces and lower work surface temperature during grinding. It is frequently a viable alternative to CBN, particularly in light of the ease of truing and dressing, and the initial wheel cost. The size of the crystalline structure plays an important role in the performance of the grinding products, with a typical sintered sol-gel having micron-sized grains. Nano-sized powders of alpha alumina have also been developed. Generally, the finer the crystallite structure, the sharper the wheel acts, since new cutting edges are more frequently being exposed than with a coarser crystallite structure. Diamond can be both: ‘natural’; or ‘synthesized’, with specific performance characteristics based on size, shape, toughness, coating applied and bond. Synthetic diamond prices have tumbled in recent years due to large volumes being produced in China and Eastern Europe, and is now cosidered as a commodity. CBN does not appear in nature and is only synthesized. Since mono-crystalline CBN was initially introduced, additional developments have been made with polycrystalline forms of CBN, and more recently, with nano-crystalline CBN abrasive, having a crystal grain size below 1µm) [16]. In 1985, Malkin reported on the current trends in CBN grinding [17]. Since then, improvements to the grain structure, shape, toughness, and price, have moved the abrasive firmly into the market place [23]. With such low manufacturing costs, CBN is following synthesised diamond towards being a commodity product. Engineered abrasive grains may also encompass diamond fibres produced by depositing diamond on to tungsten wire, using hot filament CVD [GB3, GB16]. The diamond that is produced has a poly-crystalline structure giving multiple cutting edges on each wire. Tests on a single diamond wire, bonded radially into a narrow disk, showed that once the leading edge diamond crystals were chamfered by initial wear, and many more of them became active, the wear rate reduced dramatically. Subsequent tests on multiple fibres, randomly positioned into a metal bond matrix, produced optical quality surfaces on BK7 glass, with a surface finish value of 70nm Ra, and less than 2µm sub-surface damage. Furthermore these tests suggested that diamond fibres could lead to longer wheel life, when grinding in the ductile region, compared with existing resin bond wheels.

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Zhao, et al, [15] carried out high-pressure synthesis of well-sintered millimetre-sized bulks of superhard BC2N and BC4N materials in the form of a nano-crystalline composite with diamond-like amorphous carbon grain boundaries. These new high-pressure phases of B-C-N compound have extreme hardnesses, second only to diamond. The final products are well-sintered millimetre size chunks which are translucent and yellowish in colour. The synthesized BC2N and BC4N materials have a zinc-blend structure and a face-centred cubic unit cell. The hardness measurements show that the BC2N and BC4N samples synthesized under high pressure and temperature have nominal hardnesses of 62 GPa and 68 GPa respectively, which is very close to diamond and far higher than CBN (see Figure 9). C (diamond)

B N cBN

B4C

C3N4

BC4N BC2N

Figure 9. Superhard Materials in B-C-N System [15] Zhao [15] also states that reactive sintering of diamond-SiC nano-composites, based on thorough mixing of diamond and silicon nano-size powder, can be applied to produce large specimens. It is expected that by better sample preparation, carefully designed mixing protocols, and by using silicon powder of smaller grain size, it will be possible to eliminate graphitization, reduce porosity and decrease SiC content, and thus further improve properties of diamond-SiC nano-composites. Figure 10 shows some B-C-N materials by comparison to diamond and CBN.

Phase Hardness

(GPa) Bulk Mod. (GPa)

Shear Mod. (GPa)

Diamond 70-90 443 535 Cubic BN 48 400 409 Cubic C3N4 ?? 496 332* β - C3N4 ?? 437 320* BC2N 60 408 445* BB4C 30 247 171

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Figure 10. Measured and Calculated Modulus Values [15]

3.5.1.2.Bond [UK1, R4, R3, R1, P4, J33, J30, J4, G45, G44, C36, C26, J45, J46, U46] Kovalenko [UK1] demonstrated laser sintering of a composite 80%Co-20%Sn and diamond abrasive, using up to 2 kW/cm2 power density. No evidence of graphitisation, or reduction of toughness, was detected by Kovalenko. Using a special 90% cobalt composite and diamond, clusters of the abrasive were produced. This work is highly relevant to future single-layer diamond wheel production (Figure 11).

133μm133μm133μm

Figure 11. Laser sintering of single-layer diamond [UK1] Experimental investigations by Herman [P4] have revealed that the substitution of glass binders, widely applied so far to abrasive tool engineering, for glass-crystalline binders makes it possible to obtain tools marked by high grinding performance. The work of adhesion (Wa) for grain-bond fixing was higher when glass-crystalline binders were applied. Due to the crystallization of binders the mechanisms of micro-chipping in the process of grinding could be closer which allowed the grinding power to be reduced. Herman showed it is possible to increase the fracture toughness index, compared with amorphous binders through the proper selection of binder chemical composition. Test tools made of sub-microcrystalline aluminum oxide and boron nitride, on the basis of such binders, were experimentally investigated in the course of inside diameter grinding of rings made of bearing steel. Bond bridges of porous metal-bonded diamond wheels were set up by sintering Ni-Cu-Sn coated grains in the vacuum furnace [J33]. The mechanical properties of the bond bridge, including the bending strength, shearing strength, and elastic modulus, were improved by a phosphorating treatment, a second heat treatment and a subzero treatment. However, because the metal compound of the bond bridges is still phosphor bronze, their mechanical properties are limited. The researchers tried to improve them by diffusing some high-strength metals into the bond bridges. These metals make an alloy with Cu and Sn, change the metal composition and crystalline structure of the bond bridges and impart greater strength to the bond bridge alloy, with subsequently better diamond grain retention.

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The gradual replacement of loose-abrasive wire saws by the fixed-abrasive type, for slicing silicon wafer ingots, required the development of rapid, strong and precise deposition of diamond grains onto the base wire, in order to be economically viable. The sawing machines require miles of abrasive wire to fill the bobbins. Resin-bond [J30] and electroplated-bond [J11] versions of the wire are currently on the market. With the resin-bond wire, during the heat-curing process of the resin, blue brittleness occurs in the core wire and the breaking twist strength of the core piano-wire deteriorates considerably. By adding copper powder to the bonding resin, Enomoto [J30] improved the breaking twist strength and also the resistance to heat. Figure 12 shows a schematic of the wire saw process.

work

nozzle

take-off spool

take-up spool

work

nozzle

take-off spool

take-up spool

Figure 12. Fixed Abrasive Wire Saw Machine Maekawa [J4], has developed metal bonded abrasive tools by the ‘Greentape’ laser sintering method. ‘Greentape’ refers to the tape of abrasive and binders prior to sintering. The tapes are formed in advance with the required density of abrasive grains and copper-based bond content. This method is potentially more consistent than the traditional re-coating method. The ‘Greentape’ can also be pressed before each pass of the laser, to give greater packing density. Abrasive products using diamond, CBN and aluminium oxide have been produced by this method. Tanaka [J45] has developed a grinding wheel and polishing disk by piling and curing ultraviolet-cured resin mixed with an abrasive grain. The grinding characteristics of the resin-piled grinding wheel (RP wheel) were analyzed by a grinding test. He found that the cured depth and width of the ultraviolet-cured resin increases with the duration of exposure, and that only a 5-10 second exposure time of ultraviolet light is necessary to fabricate the small surface area of the grinding wheels. He also found that not only hard and strong wheels, but also elastic wheels were obtained by the selection of resins, with the possibility to manufacture polishing disks and grinding wheels that tightly hold and uniformly distribute the abrasive grains.

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Industrial application of Rapid Prototyping as a material additive manufacturing process started fifteen years ago. Since then, several methods of building grinding wheels have been researched, based on ceramic, metallic and polymer bonds. The most popular method explored is Selective Laser Sintering (SLS). The idea of using selective laser sintering for making grinding wheels is especially attractive for low volume customized production of special profiles. The viability of this approach was reported by Hon and Gill [18], who produced polyamide/SiC matrix composites. Samples were produced using FEPA standard SiC F240 grit blended with polyamide to produce a 50/50 mix. The sample reached a UTS value of 31 MPa and a Young’s Modulus of 2100 MPa. Jackson [U46] is also looking at such laser-based rapid prototyping techniques, for micro- and nano-fabrication tools. Figure 13 shows a schematic of SLS.

scanning head

recoat roller

delivery piston

fabrication piston

laser

laser

powdersinteredlayer

scanning head

recoat roller

delivery piston

fabrication piston

laser scanning head

recoat rollercomponent being produced

delivery piston

fabrication piston

laser

laser

powdersinteredlayer

laser

powdersinteredlayer

powder

scanning head

recoat roller

delivery piston

fabrication piston

laser

laser

powdersinteredlayer

scanning head

recoat roller

delivery piston

fabrication piston

laser scanning head

recoat rollercomponent being produced

delivery piston

fabrication piston

laser

laser

powdersinteredlayer

laser

powdersinteredlayer

powder

Figure 13. Selective Laser Sintering The application of ultrasonic vibration during electroless nickel plating has been shown to improve the wetting between an abrasive grain and the nickel matrix. This grain exposure is comparable to electroplated nickel wheels [19]. The plating rate is claimed to increase with vibration amplitude, up to a maximum value of 11 µm at a frequency of 15.5 kHz. The process is experimental at this time but has potential for complex forms due to reduced tendency to build up at sharp corners, as compared to the electroplated process. Enomoto has developed a lapping film, utilizing agglomerative superfine zirconia abrasives, to overcome the environmental problems associated with loose abrasive finishing. His experiments on optical glass BK7 revealed that the surface quality obtained was as good as that obtained by polishing with ceria slurry, while the finishing efficiency was much higher. Furthermore, the possibility to achieve

33

excellent surface quality with high removal rate in large-diameter workpieces is also verified from the results of 200 mm P-TEOS finishing [J39]. 3.5.1.3. Abrasive Tool Design [U39, U41, A4, C22, GB3, GB7, GB8, GB16, G9, G17,

G19, G28, G29, G35, G42, G49, G53, G56, J3, J4, J10, J11, J18, J30, J35, U11, U14, U35, U46, C33, C35, C26, G56, G58, G60, G66, G68, G69, G74, J38, J39, J40, J41, J45, J46, J47, SD1, U46]

Tool design, in the context of this report, covers modifications to the shape or attributes of an existing tool design, or a new tool design with unique characteristics. There are many summaries that fit into this category, but only a few will be discussed in detail. The design of the grinding wheel is as critical to the success of the abrasive product as the three components that make up the abrasive composite. Design includes: the physical dimensions, the form produced on the abrasive surface, the hub material to withstand rotational and thermal stresses, the rotational error, dynamic balance, chemical resistance, and sensor integration. The future can expect to see greater applications of single-layer superabrasive wheels, especially as electroplating and brazing single-layer manufacturing techniques become faster, and their geometry becomes more accurate, since they will replace some milling tools in tool changing cabinets. The increased integration of HSK tapers and other similar spindle mounts, into the wheel body, will reduce the radial and axial error associated with collets and adapters. Advances in the friability, structure and shape of synthesised superabrasives will also improve the performance of these wheels in terms of life and form-holding. Recent tests grinding nickel alloy, using polycrystalline CBN abrasives with ultra-fine crystal structure, have recently shown G-ratio improvements up to 15 times greater than conventional polycrystalline CBN [20] with lower specific grinding energy. It is also expected that the nano-crystalline CBN will constantly regenerate micro cutting edges as radial wear progresses, much in the same way as a sol-gel sintered alumina.

Figure 14. Internal Rootforms Produced by Point Grinding [GB7]

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Re-entrant internal slots, such as dovetails and turbine disk rootforms, are traditionally produced using a large broaching machine. Turbine disk broaching machines are extremely large and contain hundreds of cutting edges to produce the slots. The sheer cost, space allowance and maintenance of such machines, makes the process expensive and destined to remain inside the turbine manufacturer plants. Recent developments in mounted point grinding have showed the viability of producing entire disks with just a few small, profiled wheels, on a modified machining centre, making future production possible at subcontractor facilities. Figure 14 shows an example of both pre-formed and finished slots in a disk, using rough and finish electroplated CBN mounted points [GB7]. The design innovation in this broaching replacement process, is in the precision and stiffness of the mounted points, and negligible form error from the 1st to 70th slot, without thermal damage. The rotational precision of a single-layer superabrasive wheel is generally a function of the grain size distribution and the electroplating method. However, micro-truing of these wheels by 2-4 μm is possible, in order to reduce the surface roughness [21]. The above process uses wheel speeds between 50-100,000 rpm, on difficult-to-grind nickel-based alloys [GB7], with 2 or 3 different wheelforms to convert the rough slot (produced by grinding, milling or electrochemical machining) into the final precise form. Since the rotor disks are extremely expensive, carbide shanks are used since they will fracture, not bend, to ensure that the spindle nose and workpiece are not damaged during an unexpected collision or if abrasive stripping occurs.

Figure 15. CVD coated abrasive burr [G56]

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Much work has been done developing CVD coatings, and their application for wear resistance, improved thermal properties, etc. However some work has also been done using the coating as a single-, or multi-layer, abrasive tool. Although this work by Hoffmeister, et al [G56], involved the manufacture of small abrasive burrs, there may be potential for creating larger wheels if the process cost can be reduced. Using a hot-filament CVD reactor, 240 tools were coated with crystal sizes up to 50 μm. Although the coating time was 90 hours, economies-of-scale can make the process viable. A close up of the CVD abrasive burr is shown in Figure 15. Full depth, traverse grinding can also be used to generate internal forms in a component, as a replacement for plunge or reciprocating grinding, which require much wider wheels. One of the biggest advantages with this approach by Weinert [G29][22] is a reduction in the total grinding force, and therefore a reduction in the tendency to produce a tapered hole. The process uses a narrow CBN grinding wheel with a tapered roughing zone and a cylindrical finishing zone. The radial infeed motion takes place outside of the workpiece. During the axial feed motion, the tapered roughing zone removes the material and the cylindrical finishing zone generates a good surface quality. Due to the tapered geometry, high material removal rates can be achieved, because the consumed power of the grinding process is distributed over a large surface area. The specific material removal rate determines the grinding wheel power. The process cannot be used for finishing square-bottomed holes unless a relief groove is incorporated in the bottom of the hole during the machining stage (see Figure 16)

Grindingwheel

work

Grindingwheel

work

Figure 16. Contact Zone in Deep Traverse Grinding [G29][22] Traverse, contour or peel grinding, as the process can known, was developed in Germany in the 1990’s. The crux of the process is that it focuses all of the material removal into a narrow contact length of less that 0.08” (1mm) to allow the maximum material removal rate with the lowest specific grinding energy. Very specific grinding

36

conditions are required to minimize wheel wear and prevent burn. This has led to the design of dedicated grinders, such as Landis, Giustina-RDC, Junker, Schaudt, etc. Until recently the process was limited to Europe due to the need for oil fluid and metal bond wheels, however, with the introduction of high strength CBN grains [23] and vitrified bonds, peel grinding is becoming a viable alternative to hard-turning in the USA, where water-based fluids are preferred. [GB23][G62].

HSG-wheel

1A1-wheel

600

400

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ctiv

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ress

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00 50 100 150 200

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atio

ncentral bore

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bs = 5 mm p = 2,71 kg/dm³ vs = 500 m/s

HSG-wheel

Figure 17. Reduced Stress Design with Radial Elongation [21] Rotational stresses during high-speed grinding can lead to failure if the hub is not correctly designed (Figure 17). The use of FEM analysis for design of the hub and the number of segments (in the case of superabrasive wheels) [21, 24], plus the improved guarding of modern machines, has reduced the risk of injury due to incorrect wheel design. Grinding wheels for vertical spindle and double-disc applications have traditionally been constructed by bonding large flat segments onto a metal core. These segments are relatively inexpensive with conventional abrasives, but require molds for a large range of segment shapes. The segments are sometimes machined with grooves to promote coolant flow and allow the chips to be cleared away. This large-segment method of manufacture is therefore not economical for superabrasive wheels. Pellet type wheels consist of large quantities of cylindrical pellets that are glued onto a flat face wheel. The pellets can be glued in a variety of patterns to produce even wear and promote better fluid flow [25]. Since the pellets are all the same size, automatic pressing techniques can be employed to reduce the manufacturing costs. They have the additional advantage that damaged sections can be repaired using a few new pellets. The wheels can be used for both single- and double-sided applications. Hoffmeister has developed self-adhesive diamond pads that replace the bonded products described above. They do not need dressing and prevent wear of the carrier disk [G58].

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In the quest for lower process cost and improved quality, machine tool companies and end users are increasingly integrating sensors into grinding machine systems for in-process and post-process control. Typically, these sensors measure displacement, motor power, grinding force, vibration and acoustic emission (AE). In some cases, the outputs from these sensors are used to indirectly predict the conditions occurring within the grinding arc. To improve the measurement accuracy, it is advantageous to make these measurements within the grinding zone and transmit them to a signal processing system. Three University research teams have developed innovative CBN wheel hubs with integral sensors to monitor the grinding process. Malkin [U35] integrated an AE sensor into the aluminium hub of the wheel, and fixed a force transducer underneath one of the CBN segments. Using Digital Signal Processing (DSP) and Radio Frequency Transmission (RFT), both signals were received by a host computer. Force monitoring was successfully applied to identify wheel rounding during truing. The AE signal was found to be sensitive to grinding and truing parameters, and could identify initial wheel-work contact to help minimize air grinding time. The technology behind this wheel has been patented. Inasaki, et al [J18], based their grinding monitoring system on an AE sensor-integrated wheel. They showed that the wheel and signal processing system could be used to reliably detect events, such as: wheel-work contact, for reduced cycle time; and wheel-dresser contact, to ensure the minimum number of truing passes are given. The ground part surface finish was also monitored by the integral AE sensor. With the help of a fuzzy neural system, based on parameters calculated from sensor data, a roughness prediction can be achieved.

source: IWT, Bremen

telemetry ring

telemetry stator

temperature sensor

Figure 18. Sensor Integrated Grinding Wheel [G19]

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Brinksmeier, et al [G19], integrated temperature, vibration and force sensors into their wheel. The temperature sensor was proved to have sufficient response time (20-50 ns) to measure the temperature close to the grinding zone, and can be compensated for changing abrasive layer thickness as the wheel wears. The piezoelectric force and vibration, thin-film, sensors are still being perfected for this application. Figure 18 shows a schematic of the wheel. The ‘Sensor Integrated’ wheel concept needs to be embraced by machine tool manufactures, in order to become seamlessly embedded into the process control, and not considered as a retrofit. Future designs must also consider the easy removal and replacement of glued vitrified CBN segments, without causing damage to the hub each time.

source: T. Tawakoli

Figure 19. Segmented T-tool Design [G75]

T-tool is a tool that combines the virtues of both a milling cutter and a grinding wheel, as shown in Figure 19. Tawakoli [G75] claims that this type of tool allows for a reduction in fluid flowrate down to that typically used for milling, with the advantage of having multiple cutting edges that are active, and those that will become active behind them, as the tool wears. By contrast, a milling cutter is replaced when the defined cutting edges are worn. The T-tool can either be produced with a solid fluted core using electroplated superabrasive grains, or, built with replaceable superabrasive segments with vitrified, resin or metallic bonds. It is also claimed that the interrupted abrasive surface between successive segments, leads to more engagement by the following segment, and hence reduces the power consumption in a way that is similar to how a reduced abrasive concentration produces larger chips. It is also claimed that as the abrasive surface wears there is no profile loss, since the contact point moves around the periphery of the tool to a position where the profile is intact. Suto et al [26] developed a similar serrated grinding wheel based on electroplated CBN, incorporating a ‘timed’, thru-the-wheel, coolant application method to take advantage of the design. 3.5.1.4.Porosity and Structure [R1, R2, R3, G45, GB32, U46] The structure of a grinding wheel is a measure of the spacing between the abrasive grain. The porosity of a grinding wheel can be described as a local effect within the

39

wheel structure, allowing the transport of fluid into the process, and giving space for the chips to form. Permeability is interconnected porosity throughout the entire structure of the abrasive composite. An analogy of porosity is closed-cell foam, where there is air trapped within each cell which can have local influence. An analogy of permeability is open-cell foam which can freely pass liquids and gases through the structure [27][28]. It has been discovered that grinding performance cannot be predicted only on the basis of porosity as a volume percentage of the abrasive tool. Instead, the structural openess (i.e., the pore interconnection) of the wheel, quantified by its permeability to fluids (air, coolant, lubricant, etc.), also influences the abrasive tool performance. Permeability also permits the clearance of material (e.g., metal chips or swarf) removed from an object being ground. Debris clearance is essential when the workpiece material being ground is difficult to machine or gummy (such as aluminium or some alloys), producing long metal chips. Loading of the grinding surface of the wheel occurs readily and the grinding operation becomes difficult in the absence of wheel permeability. A method for measuring permeability is described by DiCorleto [27], who monitored the flowrate of air, at a fixed pressure, through the structure.

Figure 20. High Aspect Ratio Grain in Wheel [27]

Figure 20 shows a structure that is produced by using high aspect-ratio (8:1) abrasive grains (filaments) within a vitrified structure [28]. The high aspect-ratio grains are produced by extruding a seeded-gel of hydrated alumina into continuous filaments, drying the filaments, cutting to the desired length, and then firing the filaments to a temperature of not more than 15000C. The alpha alumina crystallites that make up the abrasive filaments are less than 1 µm in diameter. When these abrasive filaments are formed into a grinding wheel, the bond posts are produced mainly at the interfaces where the grains touch each other, leading to a high-strength, very open, structure. During grinding, the micro-crystalline abrasive grains remain sharp until fully consumed by wear, or by truing, giving the economics to justify the higher initial cost compared to fused alumina.

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3.5.2. Testing of Tools [C10, GB4, G4, G5, G8, G37, G44, G50, J19, J30, P4, SW1,

U10, U11, U16, U34, U39] This section highlights newly developed grinding tool testing methods using both scientific and experimental techniques. For example, Shore [GB4] developed a standardized assessment method that generates "performance benefits" data of grinding wheels. The format of the data is designed to support a grinding knowledge based system (KBS). This KBS system is used to advise optimum grinding cycles for specified mass production systems and workpieces. From the standpoint of an "end-user" the general need for standard wheel testing procedures is advocated. The method proposed in this project was found to be useful for assessing abrasive products from the viewpoint of a major “end-user” of such products. Clearly, the method discussed within this paper has been developed in mind of precision cylindrical grinding operations for a major bearing manufacturer. However, the researcher considers the advocated testing method to be a realistic basis from which to develop some industrial and academically agreed basis for describing grinding wheel “performance benefits”. This work is part of a broader Intranet-based system for grinding cycle optimisation, which considers grinding cycle design, machine tool and workpiece, as well as the grinding wheel selection. Uhlmann [G8] has also developed an experimental test method for grinding wheels. The testing method allows the comparison between an existing and tested tool with good performance and a new unknown tool. After few hours the potential of the new tool can be estimated and the decision for further efforts in optimizing the process can be made. The method is based on correlations between the measured grinding forces, the tool wear and the work result. The hardness of a grinding wheel is defined as the resistance against grain pullout. This is directly influenced by the strength of the bonding at the grain and the strength of the bonding bridges. Several commercial testing systems are available to determine the hardness, including the following: • Zeiss-Mackensen tester, which correlates hardness to depth of air penetration • Grindo Sonic tester, that estimates E-Moduli from natural frequency and correlates

this to the hardness The above two methods assess the bond hardness indirectly, and against known standards. They can also be used to assess the consistency of a batch of grinding wheels and, in the case of the Grindo-Sonic, whether dangerous cracks exist inside the wheel structure. Klocke [G44] developed a grain pullout system that can establish the strength of the bond and bond bridges, using a mechanical probe, to address homogeneity problems, variation of wheel hardness, variation of concentration, and inconsistent wheel behaviour. The system pushes individual grains to determine the force at which bond fracture, grain

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pullout, or grain fracture occurs. The system has also been used in an axial direction to scratch across the wheel surface. Using an acoustic emission sensor, the signal produced by the scratch was used to identify the grain/bond failure mechanisms (see Figure 21).

Bond breakage

Grain pullout

Bond breakage

Grain pullout

Figure 21. Bond Strength Testing (G44) Several methods are routinely used for the characterization of abrasive grains. These include friability, hardness, toughness, and various abrasion and single-grit wear tests. None of these tests are application tests, hence, correlation to the actual behaviour of the grits in an abrasive product must be sought. The idea of testing the strength of individual abrasive grains and relating the results to grinding behaviour has been proposed by Brecker [29], who developed a diametral compression test of abrasive grains with the purpose of relating fracture characteristics to grinding forces. Both a quasi-static diametral compression and a roll crushing technique were used. The effective tensile strength of each grain was calculated assuming the irregular grain shape is somewhere between a sphere and a cube. Good correlation between the two methods was found, and Weibull analysis was performed on the strength data. It was concluded that the Weibull modulus was similar for the series of grains tested, and the median strengths ranked with white aluminas on the weak end to sintered aluminas on the strong end. It was further concluded that the method had significant promise as a grain characterization tool. Recent work by Breder et al [30] showed the fracture loads were size dependent and followed a Weibull scaling approach fairly well. Chandrasekaran, has standardized the wedge grinding technique at SIMR [SW1]. The method uses an inclined test component on a surface grinding machine, such that as the wheel passes over it the depth of cut increases. This method allows a range of depths of cut to be tested in a single pass. The critical depth of cut before burn can be deduced from the distance the wheel travel before the damage is detected. The method is much quicker

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to execute than normal full factorial tests and therefore more economical. Care must taken using the method as the maximum depth of cut must be within the capability of the wheel and machine, and also the burn indication may be driven horizontally to confuse the exact start of burn. It is recommended that confirmation tests are run around the region of burn. The method is described in more detail elsewhere [4]. Malkin [U34] and Ivester [U16] have described the experimental testing of single-layer CBN wheels on steel, and single-layer diamond wheels on ceramic. They used several techniques to characterize the wear, power consumption change with time, forces, surface integrity changes, surface finish, and wheel stripping point. These types of tests are typical when evaluating a new process or abrasive tool. 3.5.3. Engineered Abrasive Patterns [G37, CA4, C33, C36, SD1] Discussions on the “deterministic” performance of machining versus the “black art” of grinding, are often based on the fact that cutting tools have evenly spaced cutting edges of defined geometry (unless worn). In North America, HEDG is sometimes referred to as “micro-milling” due to the large ductile chips that are removed from the workpiece by coarse grit electroplated wheels. In an attempt to take some of the randomness out of grinding, several researchers have developed engineered grinding wheels of defined distribution and, in some cases, defined orientation.

axial profile

resulting workpiece surfaces

Δz = 300 µmV

Δz = 200 µmV

possible defect:gap in grit pattern

axial profile

resulting workpiece surfaces

Δz = 300 µmV

Δz = 200 µmV

possible defect:gap in grit pattern

Figure 22. Influence of Grit Displacement on Work Surface [G37] Aurich [G37] built and tested a wheel with defined grain structure, using kinematic simulation to develop the pattern. The CBN grains were glued onto the hub in the required pattern, followed by electroplating over the top with nickel. The aim of the work was to improve the process stability, minimise heat generation and achieve better surface quality, all without compromising the material removal rate. Figure 22 shows one pattern investigated by the simulation, and the possible defect that may occur if a single peripheral line around the wheel has no abrasive. A new generational manufacturing technology for diamond tools on brazing process cooperated with optimum distribution of grains is put forward by Fu [C36]. Monolayer brazed diamond tools with optimum grain distribution are manufactured and their

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machining performance is investigated through experiments. The testing results show that this series of diamond tools have super outstanding machining performance, which provides an innovative technology for manufacturing new generation of superbrasive tools. Compared with monolayer electroplated tools, their machining efficiency and tool life can all increase 10 times, respectively. Compared with multilayer sintered tools, their machining efficiency can be boosted 10~15 times, and their life can almost reach that of the sintered ones. Koshy [CA4] modelled both vitrified and electroplated wheels with defined grain structure, and modelled the effect of axial pitch and axial offset of adjacent rows, on the surface finish of the finished workpiece. For the best surface finish, he showed that the axial offset should be greater than zero but less than 25-40% of the average grain diameter (42 μm in his case). Tool manufacturers are constantly developing methods of optimally orienting and spacing the abrasive grain, for coated abrasive belts. One industrial technique relies on a perforated polymeric sheet that passes under falling abrasive grains and traps one grain in each perforation. The shape of the perforation preferentially traps the point of the grain rather than a flat, hence orienting it. Excess grains are blown away using compressed air. The grains are then sprayed with a solvent to soften the polymer and bond the abrasive to it. The last steps involve sintering the grains to a metal tape using a special brazing powder. The method claims to work with conventional and superabrasive grains. Another route taken by coated belt manufacturers is to engineer patterns of clustered grains onto the belt surface in the form of dots or pyramids, for example. The interrupted grinding effect they create, keeps the belt free from loading and allows greater engagement on the leading edge. As the front grains wear down, the adjacent grains can take the ‘load’ [27].

3.6. High Speed Grinding The definition of high speed in the context of this report encompasses: high tool peripheral speed; high work-speed; and high material removal rate.

3.6.1. High Wheel Speed [B12, CZ4, GB1, GB2, G5, G42, G48, G49, G50, J9, J23, R1, R2, S2, SL1, U16, U27, A10, A11, GB32, GB34, G77, J41, J42, J49, U47, CA5]

High wheel (or belt) speed grinding requires a suitable machine tool, with appropriate spindle, grinding tool, subsystems and stiffness. Several high-speed grinders have been built since early generic explorations by WZL and Bremen. Guhring capitalized on the technology 20 years ago, with Landis, Giustina/RDC, Edgetek, Elb, Blohm, Tacchella, and others following suit. More recently, high speed grinding is being researched in universities with more specific commercial and environmental benefits in mind, especially those funded by the EC, which require end-users, OEMs and Universities to work together in such projects. Figure 23 shows wheel technology versus wheel speed. Krajnik describes the recent funding received to develop a high speed cylindrical grinder in Slovenia [SL1]. The machine will use Russian made wheels with high porosity [R1],

44

with other European partners involved. A wheelspeed of 150 m/s has been discussed. Also in Eastern Europe, the Czech Republic are investigating HEDG using experimental and simulation methods (HEDG will be discussed in more detail in the following section). Kuriyagawa [J41] developed an ultra-high speed grinding (UHSG) machine which is capable of 400m/s wheel speed. It has reached the stage where it has demonstrated high machining efficiency, even in comparison with a comparative cutting method. In previous work, an ultra-high speed spindle unit (30,000 rpm, 22kW, 2×106 d.n-value) was developed. In this latest work, a UHSG machine using the spindle unit was designed and manufactured. Vibration, noise and fluid friction loss of the machine were measured and compared with conventional grinding results. The UHSG tests were performed with 300m/s wheel speed and a vitrified bonded CBN wheel. The CBN wheel having a CFRP core was specially designed. However, fluid supply was not enough in the grinding zone of the UHSG, therefore the development of a new cooling and lubricating method is needed.

Electro-plated bondingQ´w,max = 1.000 - 10.000 mm³/mms

metallic bondingQ´w,max = 50 - 250 mm³/mms

vitrified bondingQ´w,max = 50-150 mm³/mms

resin bondingQ´w,max = 50-150 mm³/mms

vitrified/bakeliteQ´w,max=10-100mm³/mms

CBN grinding wheels

conventional grinding wheels

bond

ing

type

circumferential speed of the grinding wheel vs

100 150 200 250 300

Figure 23. CBN Bond System Speed and Q’w Limitations [21]

The use of high wheel speeds for silicon nitride ceramic grinding was investigated by Kovac, up to 33,000 sfpm (176 m/s) [41], in the early 90’s. Huang [A1] is doing a similar study on zirconia, alumina and alumina-titania materials, using depths of cut of up to 0.08” (2mm). He found that the removal mechanism for the two alumina-based materials was dominated by grain dislodgement and lateral cracking along the grain boundaries, as compared to zirconia grinding, which was mainly by local micro-fracture and ductile cutting. The UltraFlex [G42, GB24] project combines high speed grinding with MQL, to produce CVT gearbox shafts in a more efficient process chain. The approach uses high material removal rate peel grinding, with fluid flowrates less than 0.01 GPH. To achieve this level of performance, the entire machine and process has to be designed from the ground up.

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Also at WZL, they are exploring wheel speeds of 30,000sfpm (150m/s) in centerless grinding, again with MQL [G49]. With such high wheelspeeds the danger of spinners will be much greater than with conventional wheel speeds (a spinner occurs when the workpiece and regulating wheel loose traction and the work spins up to the peripheral speed of the wheel). An advantage of using MQL with the process, is the increased friction between the work and regulating wheel, as compared to flood or high velocity jets. Using high wheels speeds to grind thermally sensitive TiAl intermetallic, is a recent approach by Uhlmann. The study showed CBN to be preferable to corundum, with the coolant setup critical. Much prior research has been carried out at more modest wheel speeds. Although superabrasives are dominant in high-speed grinding, conventional abrasives have also been used. Webster [28] reports specific material removal rates of 38 in3/min.in (375mm3/s.mm) on inconel 718, using a wheelspeed of 28,000sfpm (140m/s) Figure 24 shows the higher wear associated with CBN at such high rates. The grinding wheel used comprised of segments of seeded sol-gel alumina fibers bonded to a metal core, as shown in Figure 20 previously. Along the same lines, Klocke [G50] has used wheel speeds up to 33,000 sfpm (180 m/s) with grinding wheels containing micro-crystalline seeded sol-gel alumina, with specific material removal rates of 10 in3/min.in (100mm3/s.mm), on 52100 bearing steel.

s

G = 2.6 mm /mm

work material: Inconel 718,cutting speed: v = 140 m/s,depth of cut: a = 1.5 mm,

work speed: v = 15 m/min,

ce

ft spec. rem. rate:Q = 375 mm /(mm.

.s)coolant: Hysol X, 7%

flow rate: 130 l/min, 7 barwheel cleaning: 30 l/min,17 bar

'w

3

spec.

Figure 24. Radial Wear for CBN versus Alumina Fibres [28] 3.6.2. High Work Speed [C17, G48, G53, J23, J47] The benefits of high work speed are related to wheel wear, surface finish and thermal damage. The most common application of high workspeed grinding is speedstroke, however, the linear work speed may not be as high as with high-speed cylindrical grinding workpieces, but much harder to achieve than by rotation. Okuyama modified a surface grinding machine to be capable of workspeeds up to 325sfpm (100m/min) and

tock removal V'w0 500 1000 1500 2000 2500 mm3/mm 3500

0

µm

200

400

600

1000

1400

800

G = 19.0 mm /mm3 3

3 3

cBN

alumina fibres

Rad

ial w

heel

wea

r, Δ

r s

G = 2.6 mm /mm

work material: Inconel 718,cutting speed: v = 140 m/s,depth of cut: a = 1.5 mm,

work speed: v = 15 m/min,

ce

ft spec. rem. rate:Q = 375 mm /(mm.

.s)coolant: Hysol X, 7%

flow rate: 130 l/min, 7 barwheel cleaning: 30 l/min,17 bar

'w

3

spec. stock removal V'w0 500 1000 1500 2000 2500 mm3/mm 3500

0

µm

200

400

600

1000

1400

800

G = 19.0 mm /mm3 3

3 3

cBN

alumina fibres

Rad

ial w

heel

wea

r, Δ

r s

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accelerations of just over 2g [J23]. Yin [C17] used a 4-bar link to create work-speeds up to 180 fpm (55m/min) on a surface grinder. Klocke [G48, G53] worked with an OEM to produce a commercial quality machine with an acceleration of 50g in table reversal and a maximum speed of 650 fpm (200m/min). By comparison in cylindrical grinding, Koenig [21] reported wheelspeeds of greater than 50,000sfpm (250m/s) in the 80’s with q-ratios of 20, representing a workpiece peripheral speed of around 2,500sfpm (750 m/min). 3.6.3. High Removal Rate [A11, B12, C12, C17, C24, GB1, GB2, GB19, G4, G5, G35,

G42, G49, G50, J11, J12, R2, R3, C36, GB34, GB36, BE1, GB19, GB22, GB23, GB24, GB25, G77, J39, SP4]

The introduction of high performance grinding machines, in combination with the latest superabrasive technology, has lead to the development of HEDG [GB1, GB2, GB19]. The HEDG process is characterised by extremely high specific removal rates, using high wheel speed, high workspeed and high depth of cut. In conventional grinding, as the removal rate is increased the surface temperature in the grinding zone increases, and burn often results. However, if the wheel speed and table speed are increased further, the surface contact temperature reaches a peak value and then decreases, due to the greater amount of grinding energy going into the chip instead of the work. The greater thermal conductivity of superabrasives also aids the heat removal from the workpiece. Figure 25 shows the HEDG thermal effect [31].

conventionalwheel

cBNwheel

ds = 400mm; a = 6mmMaterial: 16MnCr5Q’w = 100 mm3/s.mmFluid: mineral oil

Wheelspeed(m/s)

º

Wor

kpie

cesu

rface

tem

pera

ture

(C

)

conventionalwheel

cBNwheel


Wheelspeed(m/s)

conventionalwheel

cBNwheel


Wheelspeed(m/s)

conventionalwheel

cBNwheel


Wheelspeed(m/s)

conventionalwheel

cBNwheel


Wheelspeed(m/s)

º

Wor

kpie

cesu

rface

tem

pera

ture

(C

)

º

Wor

kpie

cesu

rface

tem

pera

ture

(C

)W

orkp

iece

surfa

ce te

mpe

ratu

re (

C)

conventionalwheel

cBNwheel


Wheelspeed(m/s)

conventionalwheel

cBNwheel


Wheelspeed(m/s)

conventionalwheel

cBNwheel


Wheelspeed(m/s)

Figure 25. The HEDG Thermal Effect [31]

The use of electroplated CBN grinding wheel speeds up to 250 m/s, work speeds in excess of 100mm/s (surface grinding), depths of cut up to 30mm, and mineral oil fluid has enabled HEDG to compete with conventional cutting processes, with the advantage of better surface finish, improved surface integrity, improved form accuracy, and the possibility of using fully hardened workpieces [GB19]. Comley reports extremely high specific material removal rates of 200 in3/min.in (2000mm3/s.mm) for a 0.04” wide (1mm) low-alloy steel crankshaft thrustwall grind, and journal grinding rates of 25 in3/min.in (250 mm3/s.mm), at wheelspeeds up to 30,000sfpm

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(150m/s), using electroplated CBN in oil fluid. He has used the same machine to produce surface finish values down to 0.4 micro-inch (10nm) Ra. With the capability of a wheel changer, this class of grinding machine can combine rough and super-finish grinding in one machine. Stephenson confirms these results with his work as a partner in this project [GB19]. The specific grinding energy can be as low as 9 J/mm3 at such high removal rates. To achieve this level of performance, modern single-layer superabrasive wheels are 2-plane balanced, have rotational error less than 3µm, are able to withstand high periphery speeds (up to 250m/s), and have an even grit distribution [GB19]. Traverse, contour or peel grinding, as the process is known, is analogous to turning of a cylindrical part, with a grinding wheel instead of a single-point cutting tool. The advantage of this approach, as compared to plunge grinding, is that a single wheel can form a multi-diameter, fully hardened, shaft in only a few passes, operating in the HEDG domain. This approach is only possible using high wear resistant superabrasive wheels, typically, electroplated, vitrified, or metal-bond types, operating at high speeds for even lower wear. The wheels primarily cut the workpiece material on their sides and therefore require the abrasive to wrap around the edges. Narrow, but sufficiently stiff, wheels help reduce the contact width to reduce the thermal loading on the workpiece surface [G42, GB23]. Figure 26 shows the principle of the process, which Stephenson refers to as Superabrasive Turning (SAT). Another traverse grinding approach that reduces the contact area by tilting the grinding wheel a few degrees to create an almost point contact with the workpiece, is called Quickpoint grinding [32].

bc

vf

bc

vf

Figure 26. High Speed Traverse Grinding of Shaft [GB23]

High removal rate grinding is a relative term, since the absolute rates applicable to silicon wafer grinding are orders of magnitude lower than cast iron grinding. For a process to be called high removal rate it must be much higher than common practices, i.e. class leading. With this in mind, Zhang [C12] is using the ELID technology to HEDG ceramics. Although no removal rates are quoted in his one-page summary, it is unlikely that the performance is as high as in steel grinding, since he is focusing on ultra-precision grinding. Zhu [U47] also applies ELID at high wheel-speed and refers to the method as HELID. Zhu quotes a wheel-speed of only 6000sfpm (30 m/s) in his one-page summary,

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which is 50% higher than typical with ELID, since he has overcome some of the electrolyte turbulence issues between the electrode and the wheel.

3.7. Analysis, Simulation and Modeling

3.7.1. Analysis of Empirical Data [U26, IT3, G32, G27, G18, G16, G8, G4, C8, A7, C33, C34, C35, GB29, GB31, GB32, GB34, GB35, GB36, C24, C25, C27, C29, C30, C31, C32, GB19, GB20, GB21, GB23, GB24, GB28, G59, G61, G73, J36, J42, SP2, SP3, SP5, SP6, SP7, SD1, U48, U55, CA5, CA6] Data analysis is an important activity in research. In experimental research, data is collected for different test conditions, and has to be analyzed to identify trends, mathematical relationships and randomness. A simple form of analysis is plotting a graph and determining the equation. From this equation it will be possible to interpolate for conditions not tested but within the tested range, as well as extrapolate what would happen just outside of the tested conditions. From the equation it is also possible to fit a ‘best fit line’ or curve. The way that the curve fits the data points can be quantified using regression analysis. The following examples were gleaned from the one page-summaries, using the experience of the author, and are only a few of those typical in grinding research. Although some of these examples may be considered as models, many researchers will just present the data in graphical form with regression coefficients, and do no further interrogation. It is not of value to go through each one in detail. • Surface Finish and Active Cutting Edges [CA4, J14, J16, U17, U36, C33, GB28,

SP2, SP7, U48, CA6] • Temperature and Energy Partitioning [U44, U34, U28, U19, U18, U7, J13, IN2,

IN3, HK3, G33, G29, G25, G20, CZ4, GB1, GB2, C14, C10, A9, A8, C24, C27, C31, C34, C35, GB19, GB23, GB34, GB36, G61, SP6, CA5, CA6]

• Force and Power Prediction [A1, A6, A8, C14, G29, IR1, J2, U12, U14, U15, U36, C24, CA6]

• Wear Flats [U15, J26, J19, J13, G3] • Stress and Damage [A3, A4, C10, C13, C18, G33, IN1, IN4, IT2, U14, U44, GB23,

GB35, CA5, CA6] • Chip Thickness Estimation [U13, U12, U7, U6, IN1, G7, C2, G53, SP7] • Wheel/Work Interactions [G3, G32, G38, G39, G47, G53, U17, J42] • Stability Criteria [U32, U24, U21, U13, G51, G50, SP3] • Chip Removal Mechanism [G15, G10] • Contact Length [A8, C29, GB31]

3.7.2. Inductively Derived Models [A7, C8, C13, C14, CZ2, GB4, GB5, GB6, GB11,

G7, G20, G33, G46, G49, G51, HK2, IN1, IT3, J2, J22, P3, S2, U2, U7, U24, U26, U28, GB31, GB32, GB34, GB35, GB36, C29, C31, GB20, GB21, GB24, SP2, SP7, U48, CA5]

These total-process models are derived from data collected from experimental tests and can be used to interpolate or extrapolate untested conditions, to a known degree of correlation. Alternatively, the data can be used to train a Neural Network to change the conditions for a retest, or predict a response. Above are listed the one-summary

49

references of researchers that do not describe their modeling approach clearly enough to categorize into regression or ANN. In the following two sections, the author has attempted to fit the summaries into the appropriate categories, but there may be a few errors of judgment.

3.7.2.1.Regression Analysis [U44, U37, U36, U34, U32, U29, U19, U18, U17, U14, U3, U1, SL3, J8, G40, G23, G13, CZ4, A6, GB29, GB30, GB19, GB23, J36]

This is most common modeling approach in research since even spreadsheet software, like Excel, has some regression analysis capability. According to Brinksmeier, in grinding technology, the developed physical-empirical process models contain coefficients that can be determined through regression analysis using experimental data. In most of the process models, in which the process and output parameters have to be defined as functions of input parameters, they can be reduced to a basic form of model. The evaluation of coefficients is realized by multiple linear regression calculations. From this, the exponential form of the basic model has to be linearized by a logarithmic transformation. For the calculation of the coefficients, the least-square-error method is usually applied. Krajnik has developed a model based on response surface methodology (RSM), which integrates a central composite design (CCD) of experiments and computer aided linear regression analysis (LRA) for fitting a model to experimental data. Data analysis relates to design evaluation, which is supported by various advanced estimates of the regression matrix, and model analysis, including a full analysis of variance (ANOVA), prediction equations and response surface plots. The computer-aided single-objective optimization, solved by nonlinear programming and genetic algorithm, is applied. The results of two different optimization approaches for determination of optimal operating conditions are compared in his study. 3.7.2.2.Artificial Neuronal Networks [G41] ANN’s allow a researcher to consider qualitative information, such as a coolant nozzle or fluid type, as an input parameter of a process model. On the basis of an ANN, it is possible to calculate several output parameters at the same time, which is of advantage when calculating output parameters that show similar dependence or relationship to input parameters, e.g. F'n and F't or Rz and Ra. Furthermore, the user can implement his expertise and experience into the model as well. ANNs can be set up on the basis of the multi-layer-perceptron (MLP) concept, using hidden layers, multiple neurons at the input layer and multiple neurons at the output layer. The number of neurons in the hidden and the input layers can be varied during model development. Klocke [G41] is developing an ANN for grinding process design, that does not require the expert knowledge that a few grinding specialists may have, but may not share with others. The ANN will enable the automated creation of process models and the fast adjustment of these models to changing boundary conditions.

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3.7.3. Deductively Derived Models [A1, A8, CA4, C7, C17, UK1, U4, U7, U26, C37, GB31, GB33, J48]

This modeling approach does fit the model to existing experimental data, but uses the data plus physical principles, mathematics, and a lot of computer power, to predict the partial output from a grinding system. Above are listed the one-summary references of researchers that do not describe their modeling approach clearly enough to categorize into FEA, kinematic simulation, or molecular dynamics. In the following three sections, the author has attempted to fit the summaries into the appropriate categories, but there may be a few errors of judgment.

3.7.3.1.Finite Element Method [U44, U30, U28, U10, S1, IN4, IN2, G53, G34, G31, G27, C10, A9, GB26, G61]

The FEM uses the data gathered from the measurement to calculate the conditions within the workpiece. A requirement for the use of the FEM is a detailed modeling of the regarded process. An example of this modeling approach is determination of the temperature and stress distribution during and after grinding. Inputs to the model would be: the shape of the workpiece; the amount of the load derived from the measurement data; as well as the relevant boundary conditions. The basis for the simulation could be the Carslaw/Jaeger model. The grinding wheel would then be looked upon as a heat source that is moved with a certain speed across the ground workpiece. In front of, and behind, the contact zone the workpiece is flooded by cooling lubricant. After the modeling, the FEM is able to calculate the stresses, temperatures, gradients etc. Thereby, highly-loaded workpiece sections can be determined and the load can be minimized by choosing an adapted process. This is a similar approach to that taken by Hoffmeister [G61]. Zhang [A9] is using FEM to model the stresses caused by mechanical loading, thermal cycling and phase changes. Wang [C10] is using the method to investigate the fatigue and deformation of diamond saw blades with different structures, in order to obtain minimum and more uniform temperature distribution. Aurich [G34] uses FEM to analyze burr formation due to grinding, by looking at the thermo-mechanical aspects of the process, and the effect of the temperature on the ductility of the chip produced at the end of cut. Jain [IN2, IN4] has used FEM to determine the temperature distribution in the workpiece due to the EDDG process, and the subsequent residual stresses. Zhang [U30] is using continuum damage mechanics (CDM), and 3D non-linear FEM, to model the damage versus depth characteristics of three ceramic materials, after grinding. He can also model the damage using a contour plot, as the grit passes over the workpiece surface. 3.7.3.2.Kinematic Simulation [C2, C10, GB18, G6, G7, G9, G28, G32, G35, G36,

G37, G43, G47, HK3, IR1, J25, J28, S1, U8, U11, U13, U21, U30, U43, C30, GB27, SP3, U49, U50, U52, U57]

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Kinematic simulation can be used to model the numerous, unobservable single-grit engagements into the workpiece, to determine output parameters such as surface finish or material removal rate. The microscopic single-grit engagements depend on set-up parameters and on the specification of the grinding wheel in a non-trivial way. Due to their statistical superposition, they determine the process effects. The kinematic simulation models the single-grit engagements using penetration calculation of a numerical 3D surface of a grinding wheel and workpiece, based on the kinematics of the grinding process. Primary output quantities of the kinematic simulation are the microscopic chipping parameters. Their statistic distribution and the resulting workpiece surfaces, are dependant on the macroscopic set-up parameters, and the specification of the grinding wheel. Forces, power consumption, heat fluxes and temperatures can also be derived based on the chipping parameters. In a closed-loop simulation, the penetration kinematic can be corrected by the mechanical and thermal elastic deformations within the system. The approach can also be used to model complex kinematics such as planetary motions. A kinematical model of the wafer rotation grinding was developed by Guo [C2], to model the cutting trajectories of grits on the silicon wafer based on a mathematical model, and where the relationship between grinding surface quality and the density of grinding marks was theoretically analyzed. The formula of material removal rate (MRR) in wafer rotation grinding process was deduced based on kinematics, and the effects of the grit size and the process parameters on MRR were theoretically deduced. The results showed that, when increasing the feed rate of the grinding wheel, decreasing the rotating speed of the wafer chuck table, and using coarser grit grinding wheels, the MRR in the wafer rotating grinding increases. It was also found that there exists a critical rotating speed of the grinding wheel (about 2300rpm), beyond which the MRR evidently decreases and the spindle motor current and wafer surface roughness steeply increase. Kinematic simulation has proved to be a useful tool for Uhlmann [G6] for modeling double-sided grinding with planetary kinematics, and understanding the material removal mechanism, as well as modeling the chip thickness in ultrasonic-assisted grinding [G7]. Aurich used the method to evaluate the grinding performance of engineered superabrasive single-layer grinding wheels, with define grain distribution. The work has the potential to lower forces and temperature and produce better surface finish than random grain production wheels, and have been experimentally verified [G37]. Butler [S1] also used the same approach to predict the 3D surface topography, as well as characterizing the wheel topography, cutting grain density and wheel sharpness. 3.7.3.3.Molecular Dynamic Simulation [J29, J9, C1, C38, GB28] Molecular dynamic (MD) simulation is an effective microscopic approach to analyze the mechanism of nanometric machining from an atomistic viewpoint. Until today several applications of the method have been found dealing with indentation tests or cutting processes. Using the molecular dynamics model, the micro-mechanical

52

structure of a material is directly represented by its stoichiometric composition, atom by atom, or molecule by molecule. On their path, atoms and molecules move over time and space, obeying a micro-mechanical equation of motion (e.g. a Newtonian fluid), that is fed by the dynamic interactions with their surrounding atoms and molecules. The interaction forces are calculated on the basis of quantum-mechanically or empirical-analytically derived potential energy functions. The ensemble of atoms or molecules is highly dynamic and defined in the time-domain. The macroscopic environment is defined through the ideal gas law of thermo-dynamics, which provides the basis for the system temperature of the model. Two bodies interact with each other through their atoms (see sketch). From hence for each combination of atoms, the specific potential function is needed. The basic dimensions and units are set by lattice constant or atom size (10-10 m), bonding energy and number of atoms. For the system to develop in time, the equation of motion requires the definition of time, which is usually in the range of pico-seconds (10-12 s). The maximum model size and the simulated process time, are limited by the large number of degrees of freedom and the available calculation capacity. In principle all mechanisms, micro-mechanical and thermo-dynamical quantities and properties are active, and available at any given time during the progress of the simulation. Guo [C1] has used this approach to model the grinding of silicon using an indentation depth of one silicon atomic layer. Shimada [J29] also looked at a brittle material, to predict that the ideal surface processing approach, for minimal surface roughness and subsurface damage, is initially ductile-mode grinding to generate desired surface configuration, followed by chemo-mechanical polishing to remove subsurface damage layer.

Zhou’s emphasis was more towards the grinding of ductile materials [J9] and verified that the plastic deformation is reduced when the machining speed exceeds the material static propagation speed of plastic wave and its mechanism is completely different from that of the ordinary grinding process. Experimental results also showed the improvement of the surface integrity when the machining speed exceeds the material static propagation speed of plastic wave.

3.8. Control of Grinding This section considers the development of control algorithms, prototype hardware and verification of performance, rather than the physical manufacture of control hardware. Various control approaches are possible, including simple methods such as sequential control and fixed-stop. However, the development of more ‘intelligent’ approaches is of more interest to the reader. These approaches include Artificial Intelligence (AI) and closed-loop sensor-based control. In the Adaptive Control Constraint (ACC) approach, a chosen process quantity (such as normal force) is not allowed to exceed a fixed limit value. Even under the influence of disturbing factors such as changing work material characteristics or tool wear; this maximum

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value will not be exceeded. Usually the regulating quantity in such a system is a process quantity. Based on a chosen strategy, the process is conducted to reach a desired optimum value in the so called Adaptive Control Optimization (ACO) approach. This optimum has to be defined, for example it can either be the achieved workpiece quality, or the machining time. As input to the module (regulating quantity), this type of system operates with process, as well as output quantities. In principle, an ACO-system represents a higher level of organizational structure compared to an ACC-system [33]. Generally, using ACC permits an increase in process performance. Although the sensor application is done at a lower level according to the hierarchy of control loops, it can still be regarded as an essential part of a so called intelligent system. The major task is to get as much information as possible from the current process. With single phenomenon monitoring, this aim can often not be met, so the application of multiple sensors in one process is part of many activities to achieve an intelligent system. [34].

3.8.1. Artificial Intelligence (ACO )[B12, GB8, GB10, GB14, G4, G31, G43, G49, P1, U2, U4, U5, U6, U22, U26, GB29, U56]

Artificial Intelligence control is an intelligent control technique that produces an optimum output. The term "intelligent", in the context of process monitoring, is used in numerous publications with different meanings [35]. It is most often related to the application of artificial intelligence (Al) techniques such as knowledge-based systems, neural networks or fuzzy logic. The processing of the sensor data is usually still done in a conventional way, of course using the latest available equipment for analog to digital conversion, filtering, sampling and further calculations. It is one of the major tasks to provide a parallel processing of different sensor signals as fast as possible for extremely short response times. With respect to the hardware used, there is a range of possibilities from micro-controller to stand alone PC, and increasingly the trend is moving towards PC- based solutions, as these are also the kernels of modern computer numeric controller (CNC). Of significant importance is the interface between the machine tool and the human user. Today, a graphical user interface based on an office operating system, such as Windows, is state-of-the-art [36]. In addition, a lot of work is directed towards a modular set-up of monitoring systems, which should help to implement these systems in a machine tool surrounding. The sensor system is connected to various modules of the set-up. At first, models and threshold values have to be fixed depending on the experience of any expert. Databases, as part of a knowledge-based system, can support this essential step. The measured and processed sensor data are transmitted to succeeding modules, such as grinding databases and control modules. Depending on the type of application, direct feedback to the process according to adaptive control strategies is possible. There might be a direct connection to the CNC machine tool control unit to initiate an interrupt in case of exceeding a specific limit like spindle maximum power. As outlined the integration of sensor data in databases can support tasks in the superior control loop like planning and quality control.

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3.8.1.1.Knowledge-based [B12, G52, GB11, GB4, CZ2, C28, GB20, SP3, SP7] Holesovsky [CZ2] is developing an intelligent control system which includes a database, mathematical model definitions, control determination and controlled quantities, for the continuous control of a grinding process. One of his main issues is the verification of the influence of continuous change of work speed used in his wave-shift strategy for chatter and waviness suppression. Oliviera [B12] is developing a grinding system to be applied in the crankshaft high speed grinding using CBN wheels. The system was installed in a specially developed high-speed CBN grind machine, which contains the most important features to efficiently grind in high speed. An open-architecture CNC installed in the machine permits the two-way CNC and PC communication by a High-speed Serial Bus (HSSB). Monitoring and controlling systems were installed under a user-defined Human-Machine interface (HMI), which combines the CNC operational software and intelligent grinding routines developed by the OPF group, such as anti-collision, gap-elimination, and the acoustic mapping of the grinding wheel surface. 3.8.1.2.Fuzzy logic [A5, J18, U24, U26, GB26] Fuzzy-logic is a superset of conventional (Boolean) logic that has been extended to handle the concept of partial truth values between "completely true" and "completely false", for example, in conventional logic, the sky is cloudy or not cloudy. The sky can obviously be partly cloudy. In grinding, a fixed cycle may have 2 or 3 fixed federates, and switch points, regardless of changes in the process due to wheel wear. A fuzzy-logic control system could modify the infeed rates based on increased time constant or grinding power to a percentage of its’ original value, to achieve perfect grinding output and extend the interval between dressing. Zhang’s research aim was to establish a comprehensive fuzzy modeling technique to handle some difficult problems in grinding [A5]. A new fuzzy prediction system was developed, which can automatically select membership functions, deduce influence rules, etc. The technique was then applied to the prediction of grinding burns, selection of grinding wheels and estimation and control of grinding-induced residual stress and surface roughness. Inasaki [J18][34] developed a fuzzy control strategy to fully exploit his sensor integrated grinding wheel. Once he had set the basic grinding cycle parameters, such as maximum infeed rate, required grinding time, etc, the other inputs were determined by a fuzzy rule system based on 47 rules. To provide the optimized grinding conditions, such as actual federate, rough and finish stock, and retraction distance, the time constant, grinding power average and AE have to be used as input values. 3.8.1.3.Neural Networks [J14, G41, GB9, U58] Neural Networks are systems that simulate intelligence by attempting to reproduce the types of physical connections that occur in animal brains. Most control applications require an accurate system model for controller design. Although it is fairly easy for simple setups, it can be very cumbersome for more complicated

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systems. The system is put through a lot of tests to determine its transfer function which is essential for the design of the control system. This design is then valid for a strict set of operational limits. This approach looks at overcoming some of the classical system modeling problems by using neural networks to learn the system parameters and its transfer function. The network is then used to control the system Maksoud [GB9] is using a neural network approach to control the optimum dressing of grinding wheels, using force feedback. Klocke [G41] would like to get away from the trial-and-error approach to grinding by using ANNs to automate the creation of process models and the fast adjustment of these models to changing boundary conditions. An artificial neural network (ANN) approach was proposed by Willett [U58] for the detection of workpiece "burn", the undesirable change in metallurgical properties of the material produced by overly aggressive or otherwise inappropriate grinding conditions. The grinding acoustic emission (AE) signals for 52100 bearing steel were collected and digested to extract feature vectors that appear to be suitable for ANN processing. Two feature vectors were represented: one concerning band power, kurtosis and skew; and the other autoregressive (AR) coefficients. The result (burn or no-burn) of the signals was identified on the basis of hardness and profile tests after grinding. The trained neural network works remarkably well for burn detection. Other signal-processing approaches are also discussed, and among them the constant false-alarm rate (CFAR) power law and the mean-value deviance (MVD) prove useful.

3.8.2. Sensor-feedback with Constraint (ACC) [G19, H1, J24, U1, C11, C6, B10, A12, A2, AU1, BE1, GB19, GB21, GB23, G64, G67, GB29]

Katupitiya [A2] uses ACC techniques to control the motion of a grinding wheel when grinding spherical lenses on the ends of optical fibers. Positional control, based on encoder feedback, generates the profile, and force constraint prevents exceeding values that lead to surface and sub-surface damage. Guo [C6] uses the methods to grind the inside of a radar antenna cover using measurements taken from the outside of the cover, to give constant wall thickness. Oliviera has developed a fast control system using new acoustic emission modulated power sensor. The sensor is a low-cost alternative to piezo-electric force dynamometers and can be used for constant force grinding, or other forms of control [B10]. The superabrasive wheel profiling system by Karpuschewsky [H1] uses a wheelspeed sensor to exactly synchronize the profiling disk to the wheel surface, within a speed range. Okuyama developed a wheel-to-workpiece contact prediction system using a hydrophone and showed the acoustic power change is more significant under the conditions of smaller grinding fluid flow, higher grinding wheel speed and higher wheel porosity. This acoustic change can be used for the positioning of the grinding wheel. When the acoustic-power exceeds a certain level, a trigger signal is sent to the NC system to stop the wheel approach. By using this ACC-based system, the grinding wheel can be automatically

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positioned 20 to 100μm before wheel-to-workpiece contact under the approaching speed of 1mm/min [J24]. Using a signal from an in-process size gauge, Kurfess [U1] could calculate the change in time constant of the grinding system during extended grinding and then adjust the infeed conditions to compensate, via the feed override on the PLC. A similar approach was taken by Rowe [GB29]. The author also demonstrated real-time time constant prediction and sparkout control in 1984, but traditional CNC control systems at the time were incapable of using this information to modulate the grinding cycle accordingly [37].

3.9. In-process Monitoring and Post-process Measurement Techniques [GB20, GB21, SP7] In this section, the author has attempted to identify the common type of sensors that grinding researchers can use to monitor the grinding process. The signals from the sensors may need some filtering or signal conditioning, or may have to be used together with another sensor, to get the desired information about the process. Some comments from the authors personal experiences are added into each section where appropriate, otherwise the one-page summary should be referred to.

3.9.1. Acoustic Emission and Audible Sound [B4, B6, B8, B10, B12, B13, C10, GB10, GB14, GB15, G15, G44, J14, J18, J24, K4, P1, U24, U26, U35, U58, G66, G71, U58]

Acoustic emission (AE) is generally understood as the release of a vibrational wave emitted by a material reacting to applied stress. The acoustic emission generated during grinding and machining processes has been proved to be related to the process state and to the surface condition of the tool and workpiece. AE has become a popular sensing technique over the last 10 years. The signal bandwidth can be from 100 KHz to 2 MHz, which can rarely be used by the researcher, therefore RMS filtering is normally used to create much lower frequencies and allow the identification of events, i.e. the wheel contacting the workpiece, using threshold switching limits. The sensor does not give quantitative information about a process, unless it is calibrated to a known value and remains in the same position on the machine after calibration. This is because the acoustic path changes with wheel position in most situations, leading to attenuation of the signal. Some researchers have used the raw AE signal to look at workpiece burn and other features within the signal, however flash A/D converters and huge computer memory must be available to be able to monitor even a relatively short grinding cycle at 4MHz sampling rate and 16-bit precision [U58]. Chen has similar goals, but includes tool wear monitoring [GB14]. A unique approach taken by Oliviera [B13], is to use the AE signal from a truing device, and once-per-rev wheel sensor, to map the RMS AE across the wheel during truing. The on-screen display shows where the truer is ‘touching’ and ‘not touching’ the wheel. The method can be used to ensure the wheel is completely trued before resuming grinding.

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The minimum number of truing passes can therefore be determined using this system, and input into the PLC. 3.9.2. Force [U45, U35, U34, U32, U31, U29, U28, U24, U20, U16, U14, U9, U5, U1,

P3, J32, J2, J1, IT1, G44, G34, G17, G15, G2, GB10, C14, C13, C10, C9, CA4, CA3, B7, B6, A10, A2, A1, CZ5, BE1, C24, C32, J42, J47, J49, SD1, U49]

Force is one of the most common outputs measured from a grinding process, especially with surface grinders, where a load cell can be easily fitted onto the table. However, in cylindrical grinding, the load cell must be added to either: the workholding centers, under the wheelhead or workhead, to the ballscrew nut, or implied by calibrated deflection of a structural machine element due to the grinding force. There may be some exceptions to these comments. A unique application of force measurement was described by Klocke [G44], where he measured the force required to shear, or push out, a single-grinding grit from a wheel surface, in order to characterize the bond and abrasive. In most other grinding research cases, the measured grinding force is used as an input into a model, or used to control a process or truing initiation, using force constraint. Marsh [U20] states that the forces generated during precision grinding are small and present challenges for accurate and reliable process monitoring. These challenges are met by incorporating non-contact displacement sensors into an aerostatic spindle that are calibrated to measure grinding forces from changes in the gap between the rotor and stator. Four experiments demonstrate the results of the force-sensing approach in: detecting workpiece contact; process monitoring with small depths of cut; detecting workpiece defects; and evaluating abrasive wheel wear/loading. Results indicate that force measurements are capable of providing useful feedback in precision grinding with excellent contact sensitivity, resolution, and detection of events occurring within a single revolution of the grinding wheel. Robot based force-controlled grinding has been selected by Lauwers [BE1] as the process to finish medium/large castings (up to 1500 kg), after removing the feeders and risers by robot based oxy fuel cutting. A 20 KW hydraulic grinding end-effector has been developed and mounted via a force sensor on an industrial robot. Process models, describing the relation between material removal rate, surface quality and the process parameters set (force, feed rate, etc.) have been developed. Various stub grinding experiments have been performed on cast blocks made of steel ASTM A216 WCB. Different cup-stones with varying composition and characteristics have been investigated. The influence of the applied force (up to 600N), feed rate (up to 70mm/min) and spindle speed (up to 5000 rpm) on the material removal rate and surface quality has been studied. Avoidance of chatter (due to the use of un-stiff robots) and avoidance of burning marks (due to the high power) were important topics to be taken into account. 3.9.3. Spindle Power [A10, B2, B4, B8, B10, B11, B12, C2, C3, C8, C13, CZ2, CZ3,

GB10, G2, G14, G18, G37, IN1, J17, J18, K1, P1, P4, U1, U5, U16, U28, U34, U37, U45, GB30, GB33, C24, G75, SP41]

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As compared to force measurement, wheel motor power is simple and inexpensive to do, making it the most popular monitoring method. Phase-corrected sensors are accurate and fitted to the cables that enter the motor. There is no modification to the static stiffness of the machine, as can happen with force sensors. The drawback with the sensors is that they: are slower acting than force sensors; the power cannot be used to accurately predict the normal force; and the motor friction and eddy current losses must be subtracted from the signal before interpretation. With some modern PLCs, it is possible to obtain motor power directly from the motor-drive control board. 3.9.4. Temperature [U39, U34, U29, U28, U19, U18, U14, SW2, P3, J16, J13, IT2, IT1,

IN3, G37, G34, G23, G19, G17, GB14, GB6, GB5, GB4, GB1, GB2, CZ4, C3, B6, C35, GB35, GB36, C24, C25, C27, C31, G61, J43, J47, U48, U53, GB19, GB23, G59, CA5]

Temperature measurements are primarily used to verify thermal models developed by researchers, so that stress and thermal damage models can then be more accurately developed. Many of the fluids application studies also use temperature measurement to assess the cooling ability of the strategy. Bead thermocouples are the least expensive, and therefore the most popular method of measuring temperature [GB5]. They are bonded inside blind holes using heat conducting adhesive, but often get ground through before the peak temperature is recorded. For this reason, they work well measuring thermal fields from which the peak temperature can be extrapolated. Morgan [GB36] uses foil thermocouples sandwiched between two halves of a workpiece in a direction normal to the ground surface, and Comley [GB2] uses PVD coatings for thermal measurement. Both of these methods are designed to overcome the limitations of bead thermocouples. Brinksmeier has integrated fast acting miniature temperature sensors into a grinding wheel periphery, to observe the temperature once per revolution [G17]. An alternative approach by Ueda is to use an infrared radiation pyrometer and optical fiber, to measure grain and workpiece temperature [J13, J16]. Morgan [GB36] is also looking at fiber optic techniques for temperature measurement. 3.9.5. Wheel Wear [B2, B6, B7, B8, B9, B11, B12, B15, C3, C9, C11, C21, GB3, GB7,

GB10, GB14, G10, G11, G14, G39, G44, G35, G54, IT1, IT3, J2, J23, J26, J30, J33, P4, SP1, U1, U9, U15, U16, U24, U25, U29, U34, U39, U40, U42, C36, GB31, GB19, G69, G75, G77, G78, G79, J42, J46, J46, J47, U51]

By measurement of wheel wear, the author considers the macro-wear of the wheel surface due to repetitive grinding. It is an average value of radius change around the wheel periphery, and its’ value used to calculate either the volume of abrasive loss (to find the G-ratio) or the accumulated truing compensation required to clean up the wheel before the next test. The G-ratio is a value that is of great interest for economic analysis of a process, since it can be used to estimate tool cost per part. Several methods are used to measure wheel wear, including vernier caliper, depth micrometer, measured step height in a ground coupon, comparator, LVDT, or profilometer. Most researchers prefer

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the coupon method as the wheel does not have to be removed from the machine and it is sufficiently accurate. AE sensors can also be used with a probe to touch worn and unworn sections of a rotating wheel and use the infeed encoders to measure the difference [B12]. With superabrasive wheels, tests require a significant amount of grinding before the step in the coupon is reliably measured. 3.9.6. Workpiece Size [U1, P1, J5, G49, C6, GB29, U32, U56] Change in workpiece size can be used to determine the actual stock removed during a grinding operation. There are numerous methods to measure size. In his variable stiffness tests Zhang [U32] measured the true depth of grinding as compared to that instructed on the machine controller to create more accurate results. Size change can also be measured in-process and used as a feedback signal for precise size control through sparkout optimization [U1, P1, GB29]. Libo [J5] and Sun [U56] require size measurement to determine the stock to be removed from a turbine blade repair, to blend the airfoil surface during grinding. 3.9.7. Vibration [B9, B15, C10, C21, GB15, GB17, G17, G26, G35, U24, U25, GB32] Vibration is regarded as an instability, and is often minimized in grinding processes. Accelerometers are the accepted method of measuring vibration, with the appropriate amplifier, filters and collection system. A Fast Fourier Transform will highlight dominant frequencies from the machine tool and process, for diagnostic use. Chatter, unbalance, pump or motor vibration, and lobing, are all detectable using accelerometers. Another use for accelerometers in grinding is modal analysis of the machine-wheel-work system to look for process frequencies to avoid, since they will excite the machine [GB17]. Electro-magnetic and PZT shakers, or an instrumented hammer, can be used to sweep a range of frequencies into a machine to evaluate the response, and use this to redesign the machine stiffness and damping characteristics to make the machine more stable. Aurich used this approach to design a new grinding wheel hub with greater dynamic stability [G35]. Diniz uses the vibration signal during grinding or sparkout stage to determine the wheel condition and predict the surface finish [B9]. Hassui, also uses this approach in his research [B15]. Brinksmeier has incorporated such devices into a grinding wheel to be closer to the grinding zone [G17]. 3.9.8. Displacement [U45, U41, J5, HK3, G4, C6, G64, G67] This section refers to measuring the displacement (deflection) of the workpiece, tool or machine structure, during grinding, other than the encoders fitted to the machine slides. With robotic grinding, the true displacement of a turbine blade into a belt grinder is not accurately known since the robot is both electrically and mechanically compliant, as compared to normal grinding machine. For this reason, measurement and control strategies have been developed to replace the human being and also increase the precision of the operation [J5, U56, BE1].

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Gao relies on auxiliary displacement feedback to obtain precise feedback into the controller of his composite infeed system [HK3]. 3.9.9. Remote Monitoring [GB11] The author believes that remote monitoring of grinding machines from any location in the world will be a great tool for production engineers in the future. As well as being a diagnostic tool and possible “spy” on non-productive operators or plants, the tool will enable true manufacturing costs to be monitored through cycle time, dressing interval, wheel replacement interval, wheel consistency, and machine condition, from a single computer. Chen [GB11] is developing a knowledge support system for high efficiency precision grinding. By focusing on the key elements to be communicated within a manufacturing environment he has proposed a suitable structure for the development of a grinding knowledge management system. This provides better information support for engineers to improve grinding performance. An internet-based monitoring system is developed for decision support. 3.9.10. Grain Wear and Wheel Shape [G1, G11, G14, G47, J22, U42, U15, S1, J14, J48,

IT1, C8, CA1, HK1, U45, G71] The topography of a grinding wheel can be used to estimate: the number of active grains; the sharpness of the wheel; the wear mechanism of the grains and bond; and also can be used as an input to a simulation model. Typical methods of doing this are con-focal microscopes, SEM/AFM, conventional microscopes, 3D white-light interferometers, eyeglasses, dental replication (if the wheel cannot be removed), profilometers, etc. Lahmann has developed an opto-electrical system for measuring the surface of an electroplated superabrasive wheel to improve the manufacturing process. The device is based on triangulation and responds to surface reflectivity [G11]. A similar device, for use on a machine tool, would be useful for determining single-layer wheel condition to determine the end of effective wheel life, before the risk of stripping occurs. Tamaki [J22] has observed the three-dimensional shape of diamond abrasive grains protruding from a metal-bonded grinding wheel using a scanning laser microscope. He also developed a technique for modeling cutting edge shape, based on noise removal by wavelet analysis, and cutting edge detection by morphological processing. He found from the measurements that the cutting edges can be represented by: a triangular cone which has two types of cutting edge; double-faced cutting edge defined by rake angle and wedge angle; and one-faced cutting edge defined by rake angle and face angle. The average rake angle was 70 degrees, the average wedge angle was 112 degrees, and the average face angle was 111 degrees for SDC270 synthetic diamond grits. The self-dressing process for resin bond diamond abrasive wheels has been investigated by Sutherland [U15], using measurements of grinding force and grit wear. A technique for measuring grit wear was developed; it involves replication of the wheel surface using

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a dental molding material and stereo SEM imaging to obtain grit volume information. Based on force and volume change data, G ratios and wear coefficients were calculated. A new technique of in-situ characterization of the grinding wheel surface, for the purpose of optimizing the grinding operation including truing and dressing, was developed by Ueda [J14]. As a static evaluation, the protruding grain height from the bond, depth of chip pocket, successive cutting-edge spacing and radial/circumferential distribution of cutting points, are calculated based on the entire grinding wheel profile measured by a stylus profilometer. The micro-morphology and spatial distribution of cutting edges and their change with grinding operation can be measured by means of image processing technique. For his research a new system to measure wear flat area was developed by Bauer [CA1]. This system is mounted on the grinding machine and automates the measurement process by using computer control to automatically position the wheel and capture digital images of the wheel between grinding cycles. Image processing software is then used to analyze the digital images and measure the wear flat area. The proposed measurement system was validated using a Scanning Electron Microscope. The above wheel topography measuring systems are primarily used off of the grinding machine and post-process. Gao has developed a method of producing optically-clear fluid beams for in-process optical measurement of a grinding wheel surface. Preliminary tests have been encouraging [HK1]. 3.9.11. Single-grain Scratch and Indentation [U30, G47, G44, G39, C20, A6, A3, U54] Single-grain scratch tests are useful in observing the interactions that the grain and bond has with a workpiece surface, without the masking caused by the surrounding grains. A common method is a fly-cutter principle with a single grit oriented and bonded to the rotating plate. The grain is then traversed across a workpiece at a controlled rate and depth of cut. The single-grain indentation test is useful for determining the depth of subsurface damage due to mechanical loading, during brittle material grinding. Using both single-point and conventional grinding tests, Zhang [A3] found that the nature of deformation in a brittle material depends on its atomic bonding and lattice structure. For instance, in ceramics, dislocation motion plays an important role, but in mono-crystalline silicon, phase transformations dominate the process. He used the same approach to investigate the grinding of carbon fiber-reinforced composites. Klocke [G47] is developing a single-grain impact test using a pendulum system. The pendulum simulates the impact of a momentum afflicted hard grain on a fixed impact partner under variable contact conditions. By considering elasto-mechanical basics and aspects of tribology, the influences of the impact kinematics and contact conditions can be analyzed. Yin [C20] studied the surface integrity associated with material removal and surface generation in indentation and abrasive machining. Surface characterization of 6H-SiC

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(0001) substrates in indentation and abrasive machining was carried out to investigate micro-fracture, residual damage, and surface roughness associated with material removal and surface generation. Brittle versus plastic deformation was also studied using Vickers indention and nano-indentation. 3.9.12. Standard Material Property Tests [C7, G45, C38, CZ5] Techniques such as strength testers, static-bend testers, thermal toughness, impact testers, fatigue testers, chemical analysis systems, X-ray diffractometers, hardness testers, etc, are too numerous to list 3.9.13. Roundness and Roughness Measurement [G49, U16, CZ5] Standard equipment used for measuring roughness and roundness are stylus devices with accurate reference slides or rotary tables. Non-contacting roughness systems based on white-light interferometers, lasers, etc, are often capable of 3-D imaging. Roundness measuring systems are also useful for identifying lobing frequencies for centerless grinding stability research. No radical new techniques were uncovered during the writing of this report. 3.9.14. Ground Surface and Subsurface Analysis [G34, B1] The standard techniques used in research are: polishing and etching (to bring out the microstructure); micro- and nano-indenters (to check minute hardness changes), X-ray diffraction (to check residual stresses), taper polishing (to stretch out the top layer of material for microscopic investigation), micro-magnetic and Barkhausen sensors (for residual stress assessment in magnetic materials), and many others. No new developments were uncovered by this report.

3.10. Stability of Grinding [G12, G21, G43, G50, SP1, C32, U56, J46] The following sections include research activity which is focused on identify and improving the stability of the grinding process.

3.10.1. Vibration and Chatter [U32, U24, U21, J2, J47, G51, G35, G26, GB17, BE1, C30, GB26, SP3]

Research on chatter stability appears to have slowed down during the last 15 years after being at a peak in the 70’s to 90s. Gurney, Tobias, Inasaki, Snoeys, Brown, Koenig, Tlusty, Hahn, Miyashita, and others, can all be regarded as pioneers in this area. There are two types of vibration in grinding, forced vibration and self-excited vibration. Forced vibration comes from external sources, motors, pumps, or grinding wheel unbalance. Self-excited vibration is created by the grinding process and the machine dynamics, and often leads to a regenerative effect. Regeneration can start by using undesirable integer work/wheel ratios, exciting the natural frequency of the spindles or structure on the machine, or by a forced vibration. Initially, waves will grow on the workpiece surface resembling helical, straight-line or fish-scale patterns. Once this instability starts, the chatter will slowly regenerate onto the grinding wheel surface, albeit slower, and then back onto the workpiece. Once this happens the wheel will have to be re-trued to remove the waves.

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A systematic dynamic model has been developed by Shin [U21] to predict grinding chatter in terms of various operating parameters. The model can predict stable (or unstable) regions, surface topography and vibration amplitude. Zhang [U32] experimentally investigated the effect of static grinding stiffness on the onset of chatter with ceramic grinding, using an ultra-stiff machine tool and adjustable stiffness workholding system. He found that there was a critical stiffness value, where when below it there was a tendency to chatter. Aurich, et al, used the Finite Element Method (FEM) to optimize the dynamic behavior of a diamond wheel for grinding ceramics. Using FEM analysis, they compared the synthetic resin aluminium composite to a solid aluminium disk. Using this data, they predicted the dynamic behaviour of both grinding wheel designs, and their influence on the material removal mechanism [G35]. Weinert has looked at a different strategy to Aurich, with surface grinding, by taking the approach of varying the grinding wheel frequency small amounts after leaving the work surface, to destroy any synchronization effect that could take place during the following passes. This second pass will therefore not regenerate any waves on the wheel or work [G26]. Pearce [GB17] performs a tap test on a machine before use to identify the natural frequencies to be avoided by spindle and motor frequencies. 3.10.2. Lobing [GB15, GB18, G51, J2, SL3, C30, G71, SP3] Lobing is similar to chatter, but generally of lower frequency and only pertains to cylindrical workpieces. Profile errors with flat workpieces are usually termed waviness. Centerless grinding is a process that often suffers with lobing problems due to the centerline of the workpiece not being fixed. The cause of these lobes is usually due to incorrect setup angles on the machine that allows lobes to grow and not attenuate. This can be caused by too low a blade height, too slow regulating wheel, wheel unbalance, etc. Previous methods of analyzing centerless grinding stability have used stability diagrams encompassing the entire practical range of machine set-up angles. These diagrams, initially developed by Reeka [38], indicate that by varying the set-up angles in a prescribed manner during grinding, rapid rounding of arbitrarily lobed components can be achieved. This is verified via time-domain simulation. A novel method of predicting the lobe growth and decay during centreless grinding has now been developed by Pearce [GB18]. The method considers the locations of the three points of contact between a workpiece and the regulating wheel, the support plate and the grinding wheel. A unique circle can be drawn through these three points. The centre and radius of this circle vary continually as the workpiece rotates, in a manner dependent upon the workpiece profile and the set-up angles. An above average instantaneous radius leads, via machine stiffness, to correspondingly larger grinding force and so to an increased instantaneous depth of cut. If this occurs when the trough of a lobe is being ground, the trough will become deeper, and lobe growth will result. By contrast, if the instantaneous radius is below average when the trough is being ground, the lobe will decay. From this simple

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geometric consideration, the rates of decay and growth of a range of numbers of lobes have been calculated, across a wide range of set-up angles. The results agree well with those obtained using the previous methods. Klocke used a mathematical approach of the rounding mechanisms, to develop a simulation model to predict rounding effects in advance, in order to find an adequate range of geometrical set up parameters of the grinding gap before grinding. The outcome of this is a new design of stability diagram for stable grinding conditions, and verification of such results in practical grinding examinations [G51]. Pearce [GB15] developed a wave-shift control strategy to ensure high levels of roundness. He found that during spark-out, the roundness obtained will depend on the way in which the waviness pattern produced by the wheel eccentricity overlaps in consecutive revolutions, especially if the wheel rpm is an exact integer ratio with the work rpm. By destroying this replication every revolution of the part, using a non-integer ratio with phase shift, the lobing error with cylindrical grinding was successfully attenuated. Wu [J2] has carried out experimental and theoretical studies of centerless grinding, with respect to: clarifying the workpiece rounding process; demonstrating a new technique for monitoring the grinding process in real time; analyzing the influences of the grinding wheel irregularity and the wear deviation of regulating wheel (with guidelines for truing both wheels); and a unique technique using grinding force dynamic components was proposed to evaluate the grinding conditions for optimizing the grinding conditions. 3.10.3. Loading of Wheel Surface [CA2, C3, CZ3, GB12, GB13, G21, IR2, K3, U12,

U20] Loading of the wheel structure with workpiece or bond material causes a reduction in available chip space and possible re-deposition of material back onto the workpiece surface. It is more common with ductile materials which form long chips. When it occurs, the phenomena can produce a rapid increase in forces and spindle power, resulting in either: rapid wheel breakdown due to excessive forces, welding onto the cap of the grain resulting in it tearing out [C3]; thermal damage of the workpiece; or stripping of an electroplated bond. The tendency to load may be due to the lubricant used, the chip thickness being set too high, the work material is overheating and becoming more ductile, the grains have developed wear flats, or the bond is not conditioning in pace with grain wear, to name a few. Methods of dealing with wheel loading include: re-truing of the wheel, dressing the wheel with an abrasive stick, high-pressure cleaning jets aimed at the wheel surface, reducing the chip thickness, using mineral oil fluid, etc. With CDCF grinding, the continuous dressing action will keep the wheel clean as well as sharp, especially important when grinding ductile aerospace alloys. The use of high-pressure cleaning jets on these machines can often reduce the truing compensation per wheel revolution, since only grain sharpening is required.

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Salmon [3] used a hard titanium aluminium nitride (TiAlN) coating on an electroplated grinding wheel, followed by a layer of molybdenum disulphide (MoS2) hard lubricant to prevent loading, when grinding MAR nickel-based alloy without using cleaning jets. Koshy [CA2] found that de-clogging of diamond wheels with his EDM-grinding hybrid process was a significant benefit, in addition to the improved chip removal mechanism. Sutherland [U12] has explored the use of vibration to de-load grinding wheels, much like ultrasonic cleaning baths which are popular in industry for cleaning parts. He considered a number of adhesion theories for their role in wheel loading. Jeong also noticed that ultrasonic assisted in-process dressing prevents loading [K3]. Chen [GB12] applied a laser cleaning technique to maintain a sharp, clean, grinding wheel surface, so as to achieve high efficiency grinding. Results demonstrated that laser cleaning is feasible for grinding wheel maintenance. He has proved that the material removal rate could be increased by more than 30% when the laser cleaning technique was applied. It was also found that in a laser cleaning process, the loaded chips on the grinding wheel surface could be removed by chip fusion, thermal expulsion and evaporation under suitable laser energy flux. By using a laser cleaning model, the suitable laser energy flux could be selected to achieve effective wheel cleaning without damaging the wheel materials. He also built an image analysis system to quantitatively measure the degree of loading for control of the laser cleaning process. In the grind-hardening process, wheel loading is a possible issue that can limit the process. The process is often done dry, with a very closed wheel structures, and ductile material before the hardening process occurs. The process has been perfected over several years to be able to address such issues [G21]. 3.10.4. Stiffness Limitation [U41, U32, J27, GB26] Stiffness can either be measured statically or dynamically. Static stiffness can be determined by measuring the deflection due to a known force, whereas dynamic stiffness is measured using modal analysis to predict the harmonic response over a range of frequencies. A machine may be dynamically stiff at one frequency and dynamically weak at a different frequency, depending on resonances. Lack-of-stiffness can be classified as an instability, since it: increases the tendency to produce chatter (reduces natural frequency); results in incorrect depth of cut (wheel pushes off); increases the number of truing passes required (truer deflects), increases time constant and subsequent sparkout time requirement. Burns developed compliant ceramic finishing tools to examine the optimum compliance for fixed-abrasive grinding and polishing [U41]. In effect, Burns was adjusting the contact stiffness, since the spindle and workholding fixture were not changed. The theoretical contact stiffness can be derived from the grinding force and the wheel-work contact deformation.

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Zhang’s variable stiffness workholding system has been described above [U32]. Yokoyama [J27] investigated the influence of grinding stiffness on the depth of surface affected layer generated during grinding, that were removed during the sparkout stage.

3.11. Quality of Grinding Output [GB28, G59, G75] The following quality parameters are measured using some of the methods described in section 3.9. They represent the successful outcomes of most grinding research, i.e., good surface finish, minimum surface damage, minimum burr, and low shape error. Comments are added to a section if some innovation warrants it.

3.11.1. Surface integrity [A2, A10, B1, B3, B7, B11, C16, CZ1, CZ2, CZ3, CZ4, GB1, GB2, GB6, GB7, G2, G13, G18, G23, G29, G33, G40, G48, G54, IN4, J9, K1, R1, R2, R3, SL1, SW1, U3, U4, C34, GB34, C27, C32, GB19, GB22, GB23, G62, G77, SP4, U57]

The many summaries listed under this heading did not give specifics of what aspect of surface integrity they were considering, they just stated that it was an important goal of the project and would be measured or used to gage success. Other researchers gave the author a clue what form of ‘damage’ was of interest in their work and may have quantified the value. The expression ‘damage-free’ is often used, which is a difficult objective to achieve. Generally, good surface integrity is a very vague expression.

3.11.1.1. Phase Transformations and Depth of Damage[U44, U39, U34, J17, G25, G22, G21, G20, C14, B9, B4, A9, A7, A3, A5, BE1, G71, SD1, U48, U51, U58]

Terminology in this category includes: white-layer, martensitic transformation, grinding burn, re-hardening burn, damaged-layer, heat stain, etc. The depth of damage can be obtained by polishing and etching 3.11.1.2. Residual Stresses [A5, A9, B8, C7, C14, C15, C18, GB4, GB5, G20, G21,

G22, IT2, U30, U31, GB35, GB36, G63, G73, U48, U54, CA5] Compressive residual stresses are more desirable than tensile stresses. However, the swing from compressive to tensile should not be too extreme, otherwise lateral cracking may result under the surface. Residual stresses affect fatigue life and failure may result in crack propagation. 3.11.1.3. Surface and sub-Surface Damage [U42, U41, U33, U32, U31, U30, U14,

U8, J35, J29, J27, J8, IN1, G49, G14, G15, G3, GB16, GB3, C20, C13, C9, C2, A11, A6, A3, C38, CZ5, GB36, G73, J44, U54, J46]

The expressions surface and sub-surface damage can refer to those in 3.11.1.1, plus cracking, de-lamination, spalling, etc. Yu [C38] states that ceramics are prone to suffer from surface/subsurface crack-damage-layer after grinding, because of high grinding force and the brittleness of the material. The crack-damage-layer was investigated in his research. In his experiments, he observed that the surface/subsurface crack-damage-layer consisted of three kinds of cracks: surface micro-cracks, surface macro-cracks and subsurface

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crack system. To define the degree of damage to the machined components, the index of surface/subsurface crack damage--- Dc, was established. In an investigation of PZT ceramic grinding, Tanaka [J44] established the critical depth of cut for ductile/brittle transition to be in the range of 0.14 to 0.23 μm, at room temperature. He found that the value increased when the workpiece was heated, which would explain the improved removal mechanism obtained in laser-assisted grinding tests. 3.11.1.4. Strength Degradation [A7, CA3, GB4, GB5, J7, P2, U16, U32, GB36,

GB25] Strength degradation can include: reduction in fatigue life; reduced bend strength; reduced tensile and compressive strength, reduced creep strength, etc 3.11.1.5. Hardness Change [G49, G25, G22, G21, G20, G18, B1, A7, GB23, SP6,

U48, U58] Thermal softening and re-hardening burn are often expressions used in grinding, to indicate a change in hardness. Wear resistance can also be expressed through tribological tests., such as pin-on-disk. In the case of grind-hardening, the hardness depth, hardness profile, and stress profile are also of interest for the desired application [G22, A7]. An example stress profile is shown in Figure 27.

resi

dual

stre

ss σ

⊥

300

MPa

0

- 150

- 300

- 450

- 5000 0,05 0,1 mm 0,2

depth beneath surface

structure of etchablemartensite

white etching area (WEA)

surface grinding material: heat treatable steel (tempered)grinding wheel: Al OQ' = 2,5 mm /(mm.s), up grinding

2 3w

3

Figure 27. ResidualStresses after Grind-hardening [G22]

3.11.2. Surface Finish [A2, A5, A8, A10, B1, B2, B6, B7, B8, B9, B11, B15, CA3, C2, C9, C11, C15, C18, CZ2, CZ3, GB1, GB2, G14, G26, G29, G42, G43, G54, IN1, IT1, IT3, J1, J7, J11, J17, J21, J23, J29, J30, K2, K3, P3, P4, SL3, TU1, TU2, U6, U9, U13, U16, U27, U40, CZ5, GB31, GB33, GB36, BE1, C25, C32, GB21, GB22, GB26, G57, G58, G72, G78, J39, J40, J44, J47, J48, J49, U49, U55, U57, U58]

Another important grinding output, and the goal of many simulation models. It can be as vague as surface integrity, however, the full reference paper by the author will often describe the level of surface finish which is acceptable, and the method of measuring.

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3.11.2.1. 2-Dimensional [U31, U34] More than 90% of grinding researchers are happy to define surface finish as a 2-dimensional value, with no indication of cut-off length used or other filtering method. Ra is a vague parameter, since it does not define the tribo-mechanical nature of the surface, unlike bearing ratio, which is easily obtained and far more useful. 3.11.2.2. 3-Dimensional [C7, C22, G14, S1, J16, U31] Only one researcher exclusively refers to 3-dimensional surface finish parameters, such as Wa, and Wq, not Ra and Rq. Not surprising since but he was involved in setting up the European Standard on the topic [S1]. Several 3-D systems are on the market, produced by Zygo, Wyko, AFM, STM, confocal microscope, etc., however, often a 2-D Ra measurement is measured from the 3-D plot. The ultra-precision and nano-precision grinding researchers predominantly use 3-D assessment to observe the removal mechanism.

3.11.3. Burr Formation and Edge Chipping [C17, G34, G54, J8] For more information on burrs and de-burring method, the Technology Assessment by Prof. David Dornfeld is essential reading material. Aurich [G34] uses FEM to analyze burr formation due to grinding, by looking at the thermo-mechanical aspects of the process, and the effect of the temperature on the ductility of the chip produced at the end of cut. He observed some extremely high aspect- ratio burrs in this study. Edge chipping in ceramic grinding, and silicon dicing operations can be difficult to avoid. Sometimes the direction of cut can be changed or the work-holding method changed. External vibration can also be the cause of the problem. Defining the degree of chipping is not easily done. 3.11.4. Shape and Form [A12, C11, C19, CZ3, GB7, G12, G14, G26, G35, G54, J6, J7,

T1, U8, U37, U40, U10, U6, K1, J25, J2, GB18, GB15, CZ3, C4, CA3, B9, BE2, AU1, C28, GB20, GB23, GB24, GB25, GB26, G55, G60, G61, G67, G68, G70, K5, G72, G75, G79, J36, J47, SP3, U55, U56, J46, J49]

Geometrical tolerances, such as straightness, roundness, flatness, concentricity, all fall in this category. 3.11.5. SEM, AFM, TEM Observations [A10, A11, A12, B8, C3, C12, C13, C19, C20,

C22, G14, G15, G34, G47, G54, IT1, J32, U15, U27, U31, U33, C25, C27, C32, J43, J44, U53]

These are specific methods of looking at surfaces produced by grinding, and can either require visual interpretation of a surface, or some analysis can be performed.

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3.12. Truing and Dressing

3.12.1. Conventional Setups [U45, U40, U28, U23, U15, T1, R4, J26, J21, J14, G49, G48, G22, G9, G1, GB9, B12, B9, A12, GB33, C23, C32, G55, G71, G74, G78, SP2, SP4, SP7]

Truing and dressing are operations that can restore the geometry and sharpness of a grinding wheel. Conventional set-ups include static single-point and multi-point devices, and rotating narrow diamond disks (that traverse a wider grinding wheel) and formed diamond rolls (that plunge into a narrower grinding wheel). In most of the summaries listed below, the truing and dressing conditions were fixed during repeated grinding tests, however, the optimum speed-ratio, overlap ratio, compensation or traverse rate may not have been used if the research was not done by an experience grinding engineer. Different truing and dressing conditions may have yielded totally different results. This would not be the case with Oliviera [B12] who has worked with many industrial partners on real applications and has developed a sophisticated AE-based wheel mapping system to optimize the truing and dressing conditions. The GC cup truer system, described by Tamaki [J21], uses a slow speed, vertical-axis, cup wheel that is passed under the diamond wheel on a surface grinder. The system has been used for 10 years and is classified as conventional in this report. The method is similar to a brake-truing system, but has more precise kinematics. 3.12.2. Externally-Assisted [G16, U27] As stated earlier, there is an overlap between assisted-dressing and assisted-grinding, if the assistance is used to dress the wheel during the grinding operation. This is the case with ELID, which has been described earlier [J31].

3.12.2.1. Thermal [U23, J15, GB12, C4, C37] The precision of a formed grinding wheel is often dependent on the geometry of the truing tool. With superabrasive grinding wheels, especially diamond types, wear of the truer can be significant and ever changing. Several researchers have investigated laser-assisted truing and dressing, but with limited success. Such systems are expensive and must be protected from the hostile environment inside a grinding machine. Shin [U23] developed a system that used a laser to soften the vitrified bond CBN prior to contact with a single-point diamond truer. The laser was applied in an axial direction just ahead of the diamond truer. The effect was a very open wheel structure and some grain pullout. The CBN that Shin used was typical of that used in a standard vitrified product. However, in diamond wheel grinding, Hoffmeister and Timmer [39] found that the greater transparency of natural diamonds allowed them to withstand the energy of the laser far better than the yellow synthetic diamonds. They also determined that larger

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grit sizes are more tolerant of the laser energy, with regards to grit fracturing, due to a reduction in fracture toughness. Hoffmeister and Timmer [39] also compared traditional phenolic resin bond with high-temperature, copper filled, polyimide resin bond, showing the former took longer to profile, using a tangential laser. Their tests on resin bond wheels concluded that careful control of the bond material, and use of more transparent diamonds, will lead to a product that is tuned to the laser-truing process. A laser was explored as a non-conventional dressing tool for superabrasive grinding wheels by Dahotre [U27]. High power, continuous wave, fiber optically delivered, Nd:YAG laser was employed to dress alumina grinding wheels with varying laser power. Post-laser dressing pole-figure analysis, indicated evolution of planar crystallographic textures in the particles of re-solidified surface layer. Evolution of refined, and preferably oriented crystallographic planes, resulted in formation of individual particles (grains) with sharp vertices and edges. The surface roughness of the dressed wheel was a manifestation of the new morphologically laser modified surface. This modification in morphological features on the surface helps maintain a very high grinding efficiency. The performance of the laser-dressed grinding wheel was evaluated in comparison to the undressed wheel for a plain carbon steel pin using high-speed grinding apparatus. The weight loss in the laser-dressed grinding wheels processed at different powers is low as compared to undressed wheel after grinding. Dahotre stated that high-speed microscale grinding can be done very efficiently using the laser-dressed wheels to produce a smooth surface finish on the workpiece material The laser dressing system developed by Chen, is primarily used to clean the wheel and has been described in more detail earlier [GB12]. 3.12.2.2. Electrical [CA2, C5, C12, J20, J21, J31, SP1, U40, IFW, GB20, GB21,

GB22, G65, SD2, U47] Electro Discharge Dressing (EDD) is a non-conventional technology used for truing and dressing of conductive bond superabrasive grinding wheels. Much research work has been done on the optimum application for this technology, especially in the case of small grit size wheels. However, when it comes to the dressing of large-grit size superabrasive wheels little information is available. In this work by Sanchez [SP1] a scientific description of the mechanisms involved in bonding material removal in the EDD of large-grit size wheels, is presented. Practical application shows that very important improvements in the grinding performance of the wheels can be obtained by maximizing grit protrusion while avoiding grain loss using this technique. The system seems to be similar to ECDD [G65], and may have been changed in the translation. Shih [U40] is developing a technology to use wire EDM truing of a rotating metal bond diamond grinding wheel. The surface topography and wear mechanism of the diamond wheel after truing, and after grinding of ceramics, is investigated using a stereo SEM. The EDM’d grinding wheel, with specific form, was applied to grind a

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ceramic workpiece. Form accuracy and surface roughness of ground ceramic workpieces were studied. Kramer, then Schopf, developed an electro-chemical truing and dressing system for grinding of hard materials such as ceramics and sintered carbides, where superabrasive wheels are used. It is especially suitable for metal bonds, where truing and dressing must be done by other methods than mechanically. For this reason, the ECDM system for non-mechanical truing was developed and improved for grinding wheels with arbitrary profiles [SD2]. Denkener [G65] also considered that the technological and economical advantages of metal-bonded super abrasive grinding wheels can only be achieved by convenient conditioning methods. Conventional abrasive dressing methods, with the separation of the truing and dressing stages, cause long conditioning-times and high wear rates of the conditioning-tools. One solution to this problem is the use of the technique electro-contact discharge dressing (ECDD). The principle of this technology depends on electro-thermal bonding-removal which ensures an adequate grain protrusion of the grinding layer. The potential of this dressing method, besides generating a high grain protrusion, is that it is also possible to provide the desired tool profile in one working process. The IFW system is a single-electrode setup. Electro-Contact Discharge Dressing of metal-bonded diamond and conductive-resin bonded CBN wheels, has also been developed using a green silicon carbide cup-truer. The process is limited to diamond sizes of greater than 10μm, unlike the ELID system which can work with sub-micron sizes [J20]. 3.12.2.3. Vibration Assisted [K3, G1] An investigation of the effect of ultrasonic in-process dressing (ULID) on the grinding characteristics, was implemented by Jeong [K3]. The ULID method uses ultrasonic vibration to remove impurities on the wheel surface. The surface roughness in grinding by the ULID method was less than that of conventional grinding without ultrasonic vibration, by preventing the loading phenomena.

A new method of using ultrasonic assisted dressing with rotating dressing tools are developed and tested by Uhlmann. His studies contain continuous dressing, continuous sharpening and new conclusions about the development of the topography of the grinding tool [G1].

3.12.3. Unique Configurations [H1, G16, G14, G64, G67] CNC crushing is particularly suitable for dressing diamond grinding tools. At IFW [G64] they have developed a method of generating a precise wheel profile using the CNC-system of the machine tool, through the combined movement of its axes. Therefore it is independent of the dressing roller shape, evoking a high process flexibility. The dressing speed is continuously controlled by means of a closed-loop system. Thus no relative speed occurs between the tool and the grinding wheel. This contributes substantially to reducing the dressing roller wear. Anyway, the grinding wheel bonding system has to be

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sufficiently brittle, so that grits and bond material can be pulled out by the dressing normal forces which arise at the contact point. This is a similar approach to Karpuschewski [H1], who used to be chief-engineer at IFW. Zhao [G14] has modified the ELID technology to suit coarse-grain (46-151 μm) electroplated diamond wheels. He uses the electrolytic action to produce wear flats onto the grains to improve the roundness. The system allows him to reach surface finish Ra values down to 0.068 micro-inch (1.7nm). The advantage of large grains is that they are much easier to retain into the bond than smaller ones, with less risk of a rogue one falling out and scratching the surface. However, if one did fall out?

3.13. Ultra-precision Grinding [A2, A12, C2, C11, C12, C15, C22, J19, J31, J34, K2, K4, T1, U10, U20, U42, C32, GB20, GB21, GB25, GB28, G74, J37, J38, U47]

The author has not seen a clear definition of ultra-precision versus precision, however, the ultra-precision researchers tend to quote nanometers and angstroms, rather than microns and micro-inches. The materials ground to ultra-precision level tend to be brittle materials that need excellent optical performance, or electronic materials that need high polish and flatness for reliable circuits to be formed. In many cases, an ultra-precision grinding operation may be followed by a polishing operation. Katapitiya [A2] is grinding concentric spherical lenses onto the ends of 125 μm diameter, glass optic fibers. He nano-grinds an initial cone, and then follows this by loose abrasive blasting to generate the spherical surface. Kuriyagawa [J34] deals with new technical trends in aspherical generation for micro/meso optical parts. New technologies for ultra-precision aspherical grinding and polishing of aspherical optical lenses and molding dies are introduced. They are a parallel grinding method and a fluctuation-free grinding method. A fluctuation-free ultra-precision aspherical surface generation system was developed to achieve these methods, and demonstrated excellent grinding results with high form accuracy of 25 nm, and ultra-smooth and uniform surface roughness of single-digit nanometer (Ry). Furthermore, electro-rheological fluid assisted micro-polishing is also introduced. Stephenson [GB25] is aiming to produce ultra-precision surfaces at ten times the accuracy and with ten times greater speed than the current state of the art, with emphasis on producing “free-form” surfaces and their enormous impact on future science and technology. This project is ambitious in establishing a step-change advance in the processing route for single-digit nanometer surface finish, and precise complex-shaped surfaces, produced by grinding or other ultra-precision process. System and process research will establish key enabling technologies. These will be combined in a novel way to demonstrate a deterministic manufacturing capability at relative levels of precision in the range of 1 part in 108. This represents ultra-precision processing at an unrivalled level. The developed research equipment will be brought together at a single location to provide the UK with a unique capability for processing ultra-precise, complex-form surfaces. The developed enabling technologies and systems will have a generic impact on the fabrication of optical systems enabling diverse research areas, such as next-generation extra-large telescope optics, EUV

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(and ultimately X ray) wafer stepper optics, metrologic interferometers, optics for future space missions, compact surveillance and defence systems. Chemical Mechanical Polishing (CMP) is the enabling technology for making a smooth surface with high flatness for IC fabrication. Usually a diamond pad conditioner is used to scrape off the polishing debris from the pad top. Recently, an alternative planarization process can be achieved by polishing with a "fixed abrasive pad" (FAP). In order to dress bumps on FAP, this paper uses an amorphous diamond, a diamond-like carbon deposited by cathode arc system as the dresser for FAP. The amorphous diamond can produce a surface relief that ranges from a few nanometers to about 200 nanometers. With the addition of this dressing step on a rotary platform, FAP can renew its polishing surface 10 to 100 times before the bumps are used up. The pad cost for polishing can be reduced by at least ten folds and make FAP more desirable than slurry pad for silicon wafer manufacturer due to its intrinsic capabilities to produce flatter wafers with high polishing rate [T1]. 3.14. Economic and Environment Drivers Economic and environmental drivers often overlap with each other. In mature nations more economic can mean less waste and lower disposal cost, since there are huge repercussions for incorrect disposal. In developing nations, without such laws, economic solutions may not be environmentally conscious. The two sections that follow try to identify the purpose of the research, and the summaries have been categorized based on this. Of course, many of the researchers did not mention economic and environment drivers, so were excluded. The decision between economic and environmental, may not be accurate.

3.14.1. Economically Driven [U42, U26, U6, T1, SW1, SL3, SL1, R4, J24, J11, J3, IT3, H2, G54, G50, G49, G48, G47, G46, G39, G30, G24, G22, G18, GB4, A10, GB19, GB22, GB24, GB25, G55, G58, G62, G66, G69, G75, G77, U56]

The use of grind-hardening to replace induction hardening, has huge economic ramifications. By combining the abrasive machining and surface layer hardening, a reduction of the cycle time and manufacturing costs can be achieved. The objective of this research project was the development of dressing and grinding parameters for grind-hardening and finishing of linear guides in one set-up using the same grinding wheel specification [G22]. The economic impact of MQL versus high flowrate approaches, can result in the elimination of an entire fluid maintenance and disposal program at a major corporation. This technology will also require less pumping energy and enable a reduction of machine footprint due to smaller coolant tanks. Grinding aerospace alloys, such as inconel 718 and titanium, using cool air, has tremendous economic potential, again from the much higher value of scrap [J32]. Huang estimates that MQL could save 7-17% of the total machining cost if implemented [A10]. Zhang [A4] has developed a new grinding wheel which can save up to 70% of the use of a grinding fluid. He is possibly implying that the flowrate can be set to 30% of its’ original value.

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The development of machines that incorporate two or more processes in a single unit, are being investigated. The shape, tolerances and material specification can all dictate the economics of this approach. Models are being developed to determine the economic cross-over points [G46]. This is also the case in Delft [H2]. The use of conventional grinding wheels, containing microcrystalline Al2O3, at circumferential speeds, ranging from vc = 63 m/s up to vc = 180 m/s, and high removal rates with varying process-parameters, is being researched in Aachen. A process strategy will be developed for a stable and economical application within high-speed-machining when grinding wheels, containing microcrystalline Al2O3, are used at high cutting-speeds, and compared to CBN grinding wheels with ceramic and electroplated bonds [G50]. The main purpose of Shore’s work was to develop a method of screening grinding wheels with regards performance and cost, for a major bearing manufacturer [GB4]. Starkov is attempting to produce dressable CBN wheels that reduce overall grinding costs by 3-7 times [R4]. Chandrasekaran has developed a technique that reduces the testing time for new materials, and the number of testpieces required, by grinding a workpiece shaped like a wedge [SW1]. Tso has developed a dressing system that extends the life of fixed abrasive pads by up to 10 times, for polishing silicon wafers [T1]. On a much bigger scale, an ATP project in the US is aiming to save US industry up to $1B annually, by developing smart grinding machines [U26]. 3.14.2. Environmentally Driven [A4, A10, B2, B5, B11, G18, G40, G42, IR2, J5, J17,

J32, R1, TU1, TU2, U38, C34, GB24, G66, SP5, U56] Only one US project appears to be focused on environmentally conscious grinding research. Shih is recently developing MQL with a special Nanofluid. Nanofluid is a new class of heat transfer and anti-wear fluid, for grinding use. He will need to develop novel fluid delivery systems and wheel cooling methods, to fully exploit the fluid [U38]. There are several other researchers exploring the MQL approach. The high efficiency grinding used in the UltraFlex project [G42] may have a great potential if the process conditions operate in the HEDG domain, where little energy is directed into the work surface, and most goes into the chip. High pressure air, giving jet speeds close to Mach 1, are being mixed with water for grinding applications. The wheel cleaning and cooling effects are being targeting rather than the lubrication effect. The ambient noise from Mach 1 air was not mentioned by the researcher [IR2]. Biodegradable fluids are an ideal solution, if grinding performance is not significantly compromised. They can be directly substituted into a process with small changes made to the input parameters. However, they must be tolerant of bacteria and not biodegrade prematurely. If too many additives are introduced into the fluid to stabilize it, then the additives become more of a concern than the base fluid [B11]. On this note, Bianchi is

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investigating ways that can minimize bacterial growth and increase the life of water-based fluids.

3.15. Optimization and Grindability Assessment This section deals with the necessary experimental testing that should be done to: verify a computer model; produce output parameters with which to develop models; or obtain optimum grinding conditions through purely experimental tests.

3.15.1. Design of Experiments [SW2, SW1, SL2, G44, G41, G28, G8, GB4] We have already discussed Shore’s method [GB4] of standardized grinding tests to evaluate grinding wheels, however, this type of experimental design may also be very useful for a grinding tool supplier wishing to enter an account with view to securing business. One concern though, is that if a better grinding product is introduced into a test and forced to run in non-optimum conditions, the end-user will not benefit from this improved technology. With multiple suppliers of grinding wheels, standardization and seamless substitution into a production process may be more important than maximum performance possible. 3.15.2. Repetitive Grinding to Find Optimum [A3, B9, B12, C2, C4, C7, C8, C9, CZ1,

CZ4, GB8, G1, G2, G3, G12, G13, G16, G18, G21, G22, G23, G24, G25, G27, G30, G33, G39, G50, H2, J6, J20, K2, P2, P3, SL3, SP1, U6, U7, U8, U23, U25, U28, U40, U41, U42, BE2, C38, CZ5, GB33, BE1, C24, C27, C28, C30, C32, GB19, GB20, GB21, GB23, G63, G65, G73, J44, J45, J46, J47, SP2, SP5, SP6, U49, U53, U58, CA5]

The summaries shown in this section are numerous and it shows how popular the empirical approach to optimization is. As simulation models become more precise, the need for experimental tests at the research level will reduce. Simulation is faster, much less expensive than an assortment of machine tools, and enables new processes to be developed without building the machine tool first and then finding out from tests that it has to be re-designed. The author does not feel that grinding research is currently at a stage where empirical research work can stop, but the time is getting close. Of course, once a machine tool and process has been built based on simulation, the machine has to be run-off on real parts and proved to function as the customer is led to expect.

4. Conclusions This document, with approximately 350 summaries from 174 universities around the world, and at least a 90% hit rate of all researchers in the field, shows that fixed abrasive grinding research is not dying. Whilst metal cutting may be more popular for manufacturing researchers, there are still conferences dedicated to grinding every 1-2 years {ISAAT, SME, IGT, Aachen/Bremen, etc}, and active grinding groups within societies (SME, CIRP, ICPR, JSME, etc). The author does not regret entering the field 30 years ago, and still has a lot more work to do. There are so many technical conclusions that could be put in this section, however, it would only be a repeat of what has been said earlier

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5. References Cited and Further Reading Suggestions

5.1. Additional References used in this Report

1) S. Malkin, Grinding Technology – Theory and Applications of Machining with Abrasives, John Wiley and Sons, USA, ISBN 0-85312-756-5

2) D. Stephenson, Physical Basics in Grinding Technology, 1st European Conference on Grinding, 2003, Aachen, Germany

3) Salmon, S., 2003, The Effects of Hard Lubricant Coatings on the Performance of Electroplated Superabrasive Wheels, Int. Grinding Conf., SME.

4) J. Webster, E. Brinksmeier, C. Heinzel, M.Wittman, K. Thoens, Assessment of Grinding Fluid Effectiveness in Continuous-Dress Creep Feed Grinding, Annals of CIRP, Vol. 51/1/2002, pp. 235-240, Spain.

5) Shaji, 2003, Solid Lubricant Impregnated Wheel, Int. Journal of Machine Tool Manufacture, 43:965-972.

6) Tang, J., Pu, X., Xu, H., and Zhang, Y., 1990, Studies on Mechanisms and Improvement of Workpiece Burn During Grinding of Titanium Alloys, Annals of the CIRP, 39/1:353-356.

7) J. Webster, C. Cui, R. Mindek, Grinding Fluid Application System Design, Annals of CIRP, Vol. 44/1/1995, pp. 333-338, Netherlands.

8) S. Ninomiya, M. Iwai, T. Uematsu, K. Suzuki, and R. Mukai, Effect of the Floating Nozzle in Grinding of Mild Steels with Vitrified CBN Wheel, 6th International Symposium on Advances In Abrasive Technology (ISAAT), 2003, Bristol, England

9) K. Suzuki, Y. Tanaka, M. Iwai, T. Uematsu, and K. Tanaka, Effects of the Megasonic Floating Nozzle on Grinding Performance for Hard Materials, 6th International Symposium on Advances In Abrasive Technology (ISAAT), 2003, Bristol, England

10) H. Sakamoto, S. Shimizu, K. Suzuki, T. Uematsu, and A. Shimotokube, Effects of the Megasonic Coolant on Cylindrical Grinding Performance, 6th International Symposium on Advances In Abrasive Technology (ISAAT), Bristol, England, 2003.

11) G. Spur, and T. Brucher, Optimization of Cutting Fluid System for Grinding of Advanced Ceramics, Proc. of 1st Int. Machining and Grinding Conference, SME, Dearborn, MI, 1995.

12) Guo, C., and Malkin, S., 1992, Analysis of Fluid Flow through the Grinding Zone, Trans. of the ASME, J. of Eng. for Industry, 114:427-434.

13) S. Ebbrell. N. Woolley, Y. Tridimas, D. Allanson, and W. B. Rowe, The Effects of Cutting Fluid Application Methods on the Grinding Process, Int. Journal of Machine Tools and Manufacture, Vol. 40/2000, pp. 209-223

14) Webster, J., Fighting the Air Barrier, Manufacturing Engineering, SME, June 2004, pp. 94-96

15) Zhao, Y., He, D., Qian, J., Daemen, L., Huang, J., Pantea, C., Zhang, J., Voronin, G., Zerda, T., 2003, Novel Superhard Materials to Rival Diamond, Intertech, Vancouver.

16) Ichida, Y., and Kishi, K., 1995, The Development of Nano-crystalline cBN for Enhanced Superalloy Grinding Performance, J. Manufact. Science and Engineering, ASME, 1:349-361.

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17) Malkin, S., 1985, Current Trends in CBN Grinding Technology. Annals of the CIRP 34/2:557-563

18) Hon, K. B. and Gill, T., 2003, Selective Laser Sintering of SiC/Polyimide Composites, Annals of the CIRP, 52/1:173-176.

19) Okumiya, M., Tsunekawa, Y., Saida, T., and Ichino, R.l, 2001, Creation of High Strength Bonded Abrasive Wheel with Ultrasonic Aided Composite Plating, Surface and Coatings Technology, Frontiers of Surface Engineering, 169-170, 1/3:112-115.

20) Sunarto, and Ichida, Y., 1999, Grinding Performance of Newly Developed Polycrystalline cBN Abrasives having an Ultrafine Crystal Structure, 3rd Int. Conf. On Abrasive Technology, Brisbane, Australia.

21) König, W., Klocke, F., and Stuff, D., 1997, High Speed Grinding with CBN Wheels - Boundary Conditions, Applications and Prospects of a Future Oriented Technology, 1st French and German Conf. on High Speed Machining, Metz, June, 207-218.

22) Weinert, K., and Finke, M., 2002, Bohrungsbearbeitung in einem Uberschliff durch Innenrund-Langsschleifen, 60. Jahrbuch Schleifen, Honen, Lappen und Polieren, Vulkan-Verlag, Essen, :129-141.

23) M. Hitchiner, and S. McSpadden, Evaluation of Factors Controlling CBN Abrasive Selection for Vitrified Bonded Wheels, 6th International Symposium on Advances In Abrasive Technology (ISAAT), Bristol, England, 2003.

24) Barlow, N., Jackson, M., and Hitchiner, M., 1996, Mechanical Design of High-Speed Vitrified cBN Grinding Wheels, Proc. of IMEC, Univ. of Connecticut, USA , p. 568-570.

25) Ardelt, T., 2000, Einfluss der Relativbewegung auf den Prozess und das Arbeitsergebnis beim Planschleifen mit Planetenkinematik, PhD Dissertation, Technical Univ. of Berlin.

26) Suto, T., Waida, T., Noguchi, H., and Inoue, H., 1990, High Performance Creep Feed Grinding of Difficult to Grind Materials with New Slotted Wheel, JSPE, 24/1:39-44.

27) DiCorleto, J. 2001, Innovations in Abrasive Products for Precision Grinding, Precision Grinding and Finishing Conference, Gorham, Chicago.

28) J. Webster, and M. Tricard, Innovations in Abrasive Products for Precision Grinding, Keynote paper of CIRP, Vol. 53/2/2004, pp. 597-642, Krakow.

29) Brecker, J. N., 1974, The Fracture Strength of Abrasive Grains, Trans. Of ASME J. Eng. For Industry, 96:253-57.

30) Breder, K., Lara-Curzio, E., and Riester, L., 2004, Strength Testing System for Ceramic Grains, Ceramic Engineering and Science Proceedings, Published by the American Ceramic Society, 25.

31) Tawakoli, T., 1993, High Efficiency Deep Grinding, VDI-Verlag GmbH - Mechanical Engineering Publications Limited.

32) König, W., Schroder, B., and Treffert, C., 1993, High Speed Grinding of Any Contour Using CBN Grinding Wheels, SME 5th Int. Grinding Conf.

33) H. Tonshoff, T. Friemuth, and J. Becker, Process Monitoring in Grinding, CIRP Keynote, Vol. 51/2/2002, Spain

34) Wakuda, M, Inasaki, I., Ogawa, K., and Takahara, M., 1993, Monitoring of the grinding Process with an AE Sensor Integrated CBN Wheel, Journal of Advanced Automation Technology, 5/4:179-184.

35) W. B. Rowe, L. Yan, I. Inasaki, S. Malkin, 1994, Applications of Artificial Intelligence in Grinding, CIRP Keynote, Vol. 43/2, pp. 521-531

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36) Karpuschewski, B., Wehmeier, M., and Inasaki, I., 2000, Grinding Monitoring System Based on Power and Acoustic Emission Sensors, Annals of the CIRP 49/1:235-240.

37) Webster, J. A. and Y. Zhao, “Time Optimum Adaptive Control of Plunge Grinding", Int. Journal of Machine Tools and Manufacture, Vol. 30, # 3, p413-421, 1990.

38) D. Reeka, Uber den Zusammenhang zwschen Schleifspaltgeometrie und Rundheitsfehler beim spitzenlosen Schleifen, 1967, Doctoral thesis, Aachen.

39) Hoffmeister, H-W, and Timmer, J.-H., 2000, Laser Conditioning of Superabrasive Grinding Wheels, Industrial Diamond Review, No. 60, Booklet 586, :209-218.

40) Sexton, J., and Stone, B., 1981, The Development of an Ultrahard Abrasive Grinding Wheel which Suppresses Chatter, Annals of the CIRP, 30/1:215-218.

41) J. Kovac, et al., A Feasibility Investigation of High-speed Low Damage Grinding of Advanced Ceramics, Proc. of the %th Int. Grinding Conference, SME, 1993, Ohio

5.2. Useful Books

1) S. Malkin, Grinding Technology – Theory and Applications of Machining with Abrasives,

John Wiley and Sons, USA 2) Marinescu, W. B. Rowe, B. Dimitrov, I. Inasaki, Tribology of Abrasive Machining

Processes, Noyes Publications. 2003. William Andrew Publishing 13 Eaton Ave, Norwich, NY 13815, USA

3) Marinescu, W. B. Rowe, L. Yin, Chapter 4 : Abrasive Processes, in Handbook of Ceramics Grinding and Polishing. (Ed. I Marinescu, H K Tönshoff, I Inasaki) Noyes Publications, 1999. William Andrew Publishing 13 Eaton Ave, Norwich, NY 13815, USA

4) Sherrington, W. B. Rowe, R. J. K. Wood, Total Tribology – Towards an Integrated Approach, Professional Engineering Publishing Limited, London and Bury St Edmunds, 2002. Tribology in Practice Series of the I. Mech E. ISBN 86058393 8.

5) Marinescu, B. Rowe, B. Dimitriv, I. Inasaki: Tribology of Abrasive Machining Processes, Wiliam Andrew (2004).

6) Marinescu, H. K. Toenshoff, I. Inasaki: Handbook of ceramics grinding and polishing, Noyes Publications (1998).

7) Hahn and King, Handbook of Modern grinding Technology, Chapman and Hall, ISBN 0-412-01081-X

8) S. Salmon, Modern Grinding Process Technology 9) M. Shaw, Principles of Abrasive Processes

5.3. Useful Journals and Transactions obtained from Summaries

1) US Patent Office 2) CIRP Keynote papers, all recent years 3) ASME Winter Annual Meeting Transactions 4) SME NAMRC or NAMRI Transactions 5) Japanese Society for Precision Engineering 6) Japanese Society for Mechanical Engineering 7) Inst. Of Mechanical Engineering 8) ISAAT proceedings 9) Inst. Of Materials, Minerals and Mining

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10) EUSPEN proceedings 11) American Society for Precision Engineering 12) Multiple Manufacturing Journals are available

1. J. of the Society of Grinding Engineers 2. Key Engineering Materials 3. CIRP Annals 4. Int. J. of Machine Tools and Manufacture 5. J. of Material Science Letters 6. J. of Engineering Materials and Technology 7. J. of Materials Research 8. Materials Science Forum 9. J. of Materials Processing Technology 10. J. of Manufacturing Technology and Management 11. J. of Precision Engineering 12. Applied Optics 13. J. of Experimental Mechanics 14. Technical Digest of the SPIE 15. J. of Material Science 16. J. of Machining Science and Technology 17. Manufacturing review 18. J. of Engineering Manufacture 19. J. of International Societies for Precision Engineering and Nanotechnology 20. Robotics and Computer Integrated Manufacturing 21. Development and Life Cycle Engineering 22. Wear 23. J. of Dynamic Systems and Control 24. Int. Journal of Mechatronics 25. Int. J. of Adaptive Control and Signal Processing 26. J. of Manufacturing Systems 27. J. of Applied Thermal Engineering 28. J. of the Japan Society for Abrasive Technology (JSAT) 29. Chinese J. of Mechanical Engineering 30. Diamond and Abrasives Engineering 31. J. of Electronic Packaging 32. J. of American Ceramic Society 33. J. of Engineering Tribology 34. British Ceramic Transactions 35. Materials and Manufacturing Processes 36. Tribotest Journal 37. J. of Advanced Manufacturing Technology 38. J. of Manufacturing Science and Engineering 39. Industrial Diamond Review 40. Finer Points (Industrial Diamond Association) 41. SME J. of Manufacturing Processes 42. Diamond and Related Materials 43. Int. J. of Production Research

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A good resource for books, journal papers and conference papers on grinding, is the Abrasive Engineering Society at: www.abrasiveengineering.com . Alternatively, contact the journals’ website to look for titles of papers over the last 5 years. CIRP documents can be electronically downloaded from: www.cirp.net .

6. Background of the Author John Webster has almost 30 years of shop-floor and theoretical experience, on a range of grinding processes, within universities and private industry. His Doctoral thesis was written on adaptive control of plunge cylindrical grinding, at the University of Birmingham, in 1985. In 1989, he launched the Center for Grinding Research and Development, at the University of Connecticut, with Trevor Howes. From 1989-1998, as Associate Professor and Technical Director, Webster supervised the research of more than 50 graduate students in the area of grinding and precision manufacturing, gaining experience in all facets of precision finishing. Between 1998-2004, Webster joined Saint Gobain Abrasives and gained valuable field experience, and verified his technical approaches in many grinding applications. Webster is a Senior Member of the Society of Manufacturing Engineers and in 2004 became chairman of their Abrasives Group. In 2002, Webster became an Active Member of CIRP. He has written 16 Refereed Journal Papers, 2 Keynote papers, 50 Conference Papers, an invited AMT Technology Assessment, and 14 Trade Journal articles, on the following grinding topics: • Process control through sensor monitoring • Dynamics response and chatter suppression • Surface integrity improvement methods • Machine tool design • Coolant application optimization and nozzle design Cool-Grind Technologies was launched in September 2004, by Webster, focusing on training, grinding diagnostics, process optimization and coolant application methods and products. For more information check his website: www.cool-grind.com . 7. Acknowledgements The author would like to thank the over 200 researchers around the world, who wanted to be part of this document. The author’s membership of CIRP gained instant respect from most researchers contacted. The number of researchers that did not send a one-page summary, can be counted on two hands, making the report probably the most comprehensive review of global fixed abrasive research ever undertaken. Readers are encouraged to communicate with these researchers and seek collaboration. The author would also like to thank AMT for the opportunity to undertake the 400 hour project.

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Appendix by Country

The sequence of one-page summaries was by alphabetical order of the author for the initial 250 summaries received. The additional 100 summaries that came during preparation of the report, were added at the end of each country section, in the sequence of being received The following nomenclature is used to define the country of origin: A - Australia AU - Austria BE – Belgium B - Brazil CA – Canada C - China CZ - Czech GB – Great Britain G - Germany GR - Greece H - Holland HK - Hong Kong IN - India IR - Ireland IT - Italy J - Japan K - Korea M - Malaysia P - Poland R - Russia S - Singapore SL - Slovenia SP - Spain SW - Sweden T - Taiwan TU - Turkey UK - Ukraine U - USA

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AUSTRALIA

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A1 A Study of the Crankshaft Pin Grinding Forces Contact Information: Dr. Peter Hodgson Federation Fellow School of Engineering and Technology Fac. Of Science and engineering Deakin University, Geelong Victoria 3217 Australia Tel: +61 3 522 71251 Email: [email protected] Abstract: A study was performed to better understand the forces generated during crankshaft pin grinding, as a result models were developed to predict the forces generated during grinding. The models were verified using an experiential setup involving sophisticated strain gauge force measurements. Force modeling of the crankshaft pin grinding process requires an understanding of the complex geometrical relationships and key grinding variables that underpins the operation. It was shown from this study that important grinding variables such as the WRP and system stiffness values can significantly affect the forces produced during grinding. It was also shown that the crankshaft pin model predicted results were in agreement with the experimentally observed results. The force grinding model produced is very suitable for production applications in crankshaft pin grinding giving the grinding engineer confidence that the grinding force model developed will greatly assist in optimizing their grinding operation. Status: Completed Publications of this work: 1. Walsh, B. Baliga and P. Hodgson, A Study of the Crankshaft Pin Grinding Forces, 6th

International Symposium on Advances In Abrasive Technology (ISAAT), Bristol, UK 2. A.P. Walsh: Mathematical Modeling of the Crankshaft Pin Grinding Process

(DeakinUniversity - Preprint PhD. Thesis, 2003).

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mailto:[email protected]

A2 Nano Grinding of Slender Brittle Structural Elements – Machining Optical Fibres Contact Information: Dr Jayantha Katupitiya Senior Lecturer (Mechatronics) School of Mechanical and Manufacturing Engineering The University of New South Wales Sydney NSW 2052 AUSTRALIA Tel: +61 2 9385 4096 Fax: +61 2 9663 1222 Email: [email protected] http://www.mech.unsw.edu.au/research/mechatronics/index.html Abstract: This research investigates purely mechanical means of producing highly concentric spherical lenses at the endfaces of optical fibers by means of nano-grinding using fixed abrasives. Optical fibres are extremely brittle and have a diameter of 125 microns. The production process has two stages. First conical lenses are produced in a grinding process that ensures excellent concentricity. Then the conical lenses are transformed to spherical lenses using a novel process called loose abrasive blasting. The cone grinding is carried out on a nano-grinding machine that has a sophisticated control system that enables the production of precision conical lenses. The blasting is carried out on a diamond blasting machine. Key Issues: • Precision motion control to move grinding disc to maintain disc quality • Controlling grinding forces to prevent workpiece structural failure • Grinding parameter control to optimize surface quality Status: On going Publications of this Work: 1. Gharbia, Y.A., Katupitiya, J., " Loose abrasive Blasting as an Alternative to Slurry Polishing

of Optical Fiber Endfaces," International Journal of Machine Tools and Manufacture, Volume 43, Issue 14, November 2003, Pages 1413-1418

2. Gharbia, Y.A., Milton, G., Katupitiya, J., "The Effect of Optical Fiber Endface Surface Roughness on Light Coupling," SPIE, Vol. 6 5252-31, 2003. Gharbia, Y.A., Katupitiya, J., "Experimental Determination of Optimum Parameters for Grinding of Optical Fiber Endfaces," International Journal of Machine Tools and Manufacture, Volume 44, Issues 7-8, June 2004, Pages 725-731

3. G. Milton, Y. Gharbia, and J. Katupitiya "Automated Precision Centering of Optical Fibers for Nano-grinding" 3rd IFAC Symposium on Mechatronic Systems, September 6-8, 2004, Manly Beach, Sydney, Australia

4. G. Milton, Y. Gharbia, J. Katupitiya, "Mechanical fabrication of precision microlenses on optical fiber endfaces," SPIE's 49th annual meeting: in optical Science and Technology, 2-6 August 2004, Denver, Colorado, USA

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http://www.mech.unsw.edu.au/research/mechatronics/index.html

5. G. Milton, Y. Gharbia, J. Katupitiya "Vision Based Ultra-precision Centeringof Optical Fibers for Micro Lens Fabrication" 2004 IEEE/RSJ International Conference on Intelligent Robots and Systems, September 28 - October 2, 2004, Sendai, Japan.

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A3 Damage-Free Grinding of Brittle Materials Contact Information: Professor Liangchi Zhang School of Aerospace, Mechanical and Mechatronic Engineering The University of Sydney NSW 2006 Australia Tel: +61-2-9351-2835 Fax: +61-2-9351-7060 Email: [email protected] Website: http://nt-542.aeromech.usyd.edu.au/ Abstract: This research tries to understand the scientific mechanisms of material removal of various brittle materials when subjected to surface grinding. The ultimate goal is to achieve damage-free grinding without residual dislocations, phase transformations or cracks. With the aid of both single-point and conventional grinding tests, the study found that the nature of deformation in a brittle material depends on its atomic bonding and lattice structure. For instance, in ceramics, dislocation motion plays an important role, but in monocrystalline silicon phase transformations dominate the process. Key Issues of the Work: • A deep understanding of the mechanisms in damage-free grinding. • Some new techniques for examining the subsurface damages in ground components of brittle

and hard materials. • A new constitutive theory for describing the mechanics behaviour of monocrystalline silicon

with multiple phase transformations under grinding. Status: On-Going Publications of this work: 1. I Zarudi and L Zhang, Subsurface damage in single-crystal silicon due to grinding and

polishing, Journal of Materials Science Letters, 15 (1996) 586-587. 2. I Zarudi, L Zhang and Y W Mai, Subsurface damage in alumina induced by single point

scratching, Journal of Materials Science, 31 (1996) 905-914. 3. I Zarudi and L Zhang, Effect of ultra-precision grinding on the microstructural change in

silicon monocrystals, Journal of Materials Processing Technology, 84 (1998) 148-158. 4. I Zarudi, L Zhang and D Cockayne, Subsurface structure of alumina associated with single-

point scratching, Journal of Materials Science, 33 (1998) 1639-1654. 5. I Zarudi and L Zhang, Initiation of dislocation systems in alumina in single-point grinding,

Journal of Materials Research, 14 (1999) 1430-1436. 6. I Zarudi and L Zhang, On the Limit of Surface Integrity of Alumina by Ductile-Mode

Grinding, Trans ASME, Journal of Engineering Materials and Technology, 122 (2000) 129-134.

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7. L Zhang, I Zarudi, Towards a Deeper Understanding of Plastic Deformation in Mono-Crystalline Silicon, International Journal of Mechanical Science, 43 (2001) 1985-1996.

8. H Helbawi, L Zhang and I Zarudi, Difference in Subsurface Damage in Indented Specimens with and without Bonding Layers, International Journal of Mechanical Science, 43 (2001) 1107-1121.

9. T Vodenitcharova and L Zhang, A mechanics prediction of the behaviour of mono-crystalline silicon under nano-indentation, International Journal of Solids and Structures, 40 (2003) 2989-2998.

10. T Vodenitcharova and L Zhang, A new constitutive model for the phase transformations in mono-crystalline silicon, International Journal of Solids and Structures , 41 (2004) 5411-5424.

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A4 Development of Eco-Grinding Technologies Contact Information: Professor Liangchi Zhang School of Aerospace, Mechanical and Mechatronic Engineering The University of Sydney NSW 2006 Australia Tel: +61-2-9351-2835 Fax: +61-2-9351-7060 Email: [email protected] Website: http://nt-542.aeromech.usyd.edu.au/ Abstract: This study intends to develop some eco-grinding technologies to minimize the environment pollution problem caused by the grinding fluid which often contains harmful chemicals. The research leads to a new grinding wheel system, the applicability of cold air and oil-mist and their impacts on the surface integrity of ground components. Key Issues of the Work: • A patented new wheel system which can save up to 70% of the use of grinding fluid. • Developed theoretical models for property predictions of grinding systems. • Achieved understanding of the mechanisms of surface integrity formation when grinding

with cold air and oil-mist. Status: On-Going Publications of this work: 1. L Zhang, T Nguyen and B Oliver, A grinding wheel assembly and a method of grinding,

Patent 20044901614. 2. T Nguyen and L Zhang, An assessment of the applicability of cold air and oil mist in surface

grinding, Journal of Materials Processing Technology, 140 (2003) 224-230. 3. T Nguyen and L Zhang, Modelling of the mist formation in a segmented grinding wheel

system, International Journal of Machine Tools and Manufacture, 45 (2005) 21-28. 4. T Nguyen, L Zhang and I Zarudi, The effect of liquid nitrogen at surface grinding on the

microstructure of a quenchable steel, in: Proceedings of the 7th International Conference on Progress of Machining Technology (ISBN: 7-80183-500-X), edited by W-Y Chen, Y Yamane, R Fan and A Akio, Aviation Industry Press, Beijing, China (2004) 699-704.

5. K Xiao and L Zhang, Residual stresses in steel components ground without liquid coolant, in: Proceedings of the 7th International Conference on Progress of Machining Technology (ISBN: 7-80183-500-X), edited by W-Y Chen, Y Yamane, R Fan and A Akio, Aviation Industry Press, Beijing, China (2004) 714-718.

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A5 Fuzzy Prediction of Grinding Contact Information: Professor Liangchi Zhang School of Aerospace, Mechanical and Mechatronic Engineering The University of Sydney NSW 2006 Australia Tel: +61-2-9351-2835 Fax: +61-2-9351-7060 Email: [email protected] Website: http://nt-542.aeromech.usyd.edu.au/ Abstract: This research aims to establish a comprehensive fuzzy modeling technique to handle some difficult problems in grinding. A new fuzzy prediction system was developed, which can automatically select membership functions, deduce influence rules, etc. The technique was then applied to the prediction of grinding burns, selection of grinding wheels and estimation and control of grinding-induced residual stress and surface roughness. Key Issues of the Work: • A fuzzy modeling technique which is capable to effectively handle complexity involved in

grinding • Much improved selection of grinding conditions for desirable grinding results (surface burns,

surface roughness, wheel selection and residual stresses) Status: On-Going Publications of this work: 1. Y Ali and L Zhang, A methodology for fuzzy modelling of engineering systems, Fuzzy Sets

& Systems, 118 (2001) 181-197. 2. Y Ali and L Zhang, Estimation of surface residual stresses induced by creep-feed grinding

using a fuzzy logic approach, Journal of Materials Processing Technology, 63 (1997) 875-880.

3. Y Ali and L Zhang, Surface roughness prediction of ground components using a fuzzy logic approach, Journal of Materials Processing Technology, 89-90 (1999) 561-568.

4. Y Ali and L Zhang, A fuzzy model for predicting burns in surface grinding of steel, International Journal of Machine Tools and Manufacture, 44 (2004) 563-571.

5. Y Ali and L Zhang, A fuzzy logic approach for grinding wheel selection, in: Progress of Cutting and Grinding, V.3, edited by N Narutaki, D Chen, Y Yamane and A Ochi (Proceedings of the 3rd International Conference on Progress Cutting & Grinding, Osaka, Japan, 19-22 November 1996), Japan Society for Precision Engineering (1996) 488-493.

A6 Grinding of Fibre-Reinforced Composites

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Contact Information: Professor Liangchi Zhang School of Aerospace, Mechanical and Mechatronic Engineering The University of Sydney NSW 2006 Australia Tel: +61-2-9351-2835 Fax: +61-2-9351-7060 Email: [email protected] Website: http://nt-542.aeromech.usyd.edu.au/ Abstract: This research aims to reveal the processing-property-grindability relationship of composites reinforced by carbon fibres. To understand the detailed roles of fibres in the process of material removal, investigations on single-point cutting was also carried out in addition to grinding. It was found that fibre direction has the most significant effect on the subsurface damage of the ground composite workpieces. Key Issues of the Work: • A deep understanding of the processing-property-grindability relationship of carbon fibre-

reinforced composites. • A new mechanics model for cutting force prediction. • Characterisation of subsurface damage. Status: On-Going Publications of this work: 1. N S Hu and L Zhang, A study on the grindability of multidirectional carbon fibre-reinforced

plastics, Journal of Materials Processing Technology, 140 (2003) 152-156. 2. N S Hu and L Zhang, Some observations in grinding unidirectional carbon fibre-reinforced

plastics, Journal of Materials Processing Technology, 152 (2004) 333-338. 3. M Mahdi and L Zhang, A Finite Element Model for the Orthogonal Cutting of Fibre-

Reinforced Composite Materials, Journal of Materials Processing Technology, 113 (2001) 373-376.

4. X M Wang and L Zhang, An experimental investigation into the orthogonal cutting of unidirectional fibre reinforced plastics, International Journal of Machine Tools and Manufacture, 43 (2003) 1015-1022.

5. L Zhang, H Zhang and X Wang, A new mechanics model for predicting the forces of cutting unidirectional fibre-reinforced composites, Machining Science and Technology, 5 (2001) 293-305.

6. N S Hu and L Zhang, Grindability of unidirectional fibre-reinforced composites, The 13th Int Conf Composite Materials (ICCM-13), Beijing, China, 25-29 June 2001. Paper No: ID1343 (Proceedings in CD), 8 pages.

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A7 Grinding-Hardening of Steel Components Contact Information: Professor Liangchi Zhang School of Aerospace, Mechanical and Mechatronic Engineering The University of Sydney NSW 2006 Australia Tel: +61-2-9351-2835 Fax: +61-2-9351-7060 Email: [email protected] Website: http://nt-542.aeromech.usyd.edu.au/ Abstract: This research develops a new grinding technology which uses the grinding heat as the energy source for surface hardening. The aim is to complete precision grinding and surface hardening of a steel component simultaneously. The mechanisms of surface integrity formation were also explored. It was found that the degree of surface hardening and the properties such as wear resistance and fatigue life of a component ground in this way can be controlled by varying the grinding parameters. Key Issues of the Work: • A patented grinding-hardening technology. • A deep understanding of the surface integrity generation of components by the grinding-

hardening technology. • A modeling technique for the process. Status: On-Going Publications of this work: 1. L Zhang and I Zarudi, Steel Surface Treatment by Grinding, Patent PQ7858 & PR6623. 2. I Zarudi and L Zhang, A revisit to some fundamental wheel-workpiece interaction problems

in surface grinding, International Journal of Machine Tools and Manufacture, 42 (2002) 905-913.

3. I Zarudi and L Zhang, Mechanical property improvement of quenchable steel by grinding, Journal of Materials Science, 37 (2002) 3935-3943.

4. I Zarudi and L Zhang, Modelling the structure changes in quenchable steel subjected to grinding, Journal of Materials Science, 37 (2002) 4333-4341.

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A8 Mechanics Modeling of Grinding Contact Information: Professor Liangchi Zhang School of Aerospace, Mechanical and Mechatronic Engineering The University of Sydney NSW 2006 Australia Tel: +61-2-9351-2835 Fax: +61-2-9351-7060 Email: [email protected] Website: http://nt-542.aeromech.usyd.edu.au/ Abstract: This research aims to understand the mechanics of some important grinding problems. Emphasis was placed on the modeling of deformation of grinding systems. The models developed include grinding forces, wheel-work contact length, surface roughness, elastic modulus of grinding wheels, and heat flux profile of due to surface grinding. Key Issues of the Work: • Achieved an understanding of the mechanics behaviour of wheel deformation, heat flux

formation, contact length variation and surface roughness generation in brittle and ductile work-materials.

• Developed some theoretical models for property prediction. Status: On-Going Publications of this work: 1. L Zhang, T Suto, H Noguchi and T Waida, An overview of applied mechanics in grinding,

Manufacturing Review, 5 (1992) 261-273. 2. L Zhang, T Suto, H Noguchi and T Waida, Applied Mechanics in Grinding, Part III: A new

formula for contact length prediction and a comparison of available models, International Journal of Machine Tools and Manufacture, 33 (1993) 587-597.

3. L Zhang, T Suto, H Noguchi and T Waida, Applied Mechanics in Grinding, Part II: Modelling of elastic modulus of wheels and interface forces, International Journal of Machine Tools and Manufacture, 33 (1993) 245-255.

4. G Lu and L Zhang, Further remarks on the modelling of elastic modulus of grinding wheels, International Journal of Machine Tools and Manufacture, 34 (1994) 841-846.

5. L Zhang, Grindability of some metallic and ceramic materials in CFG regimes, International Journal of Machine Tools and Manufacture, 34 (1994) 1045-1057

6. L Zhang, T Suto, H Noguchi and T Waida, A study of creep-feed grinding of metallic and ceramic materials, Journal of Materials Processing Technology, 48 (1995) 267-274.

7. L Zhang, T Suto, H Noguchi and T Waida, A study of creep-feed grinding of metallic and ceramic materials, Journal of Materials Processing Technology, 48 (1995) 267-274.

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A9 Mechanisms of Residual Stresses Induced by Surface Grinding Contact Information: Professor Liangchi Zhang School of Aerospace, Mechanical and Mechatronic Engineering The University of Sydney NSW 2006 Australia Tel: +61-2-9351-2835 Fax: +61-2-9351-7060 Email: [email protected] Website: http://nt-542.aeromech.usyd.edu.au/ Abstract: This research aims to achieve a deep understanding of the mechanisms of residual stresses due to surface grinding. The finite element method was used to simulate the stresses caused by mechanical loading, thermal cycle and phase change. Both the effects of the individual factors and their coupling were investigated. Key Issues of the Work: • Modeling techniques and algorithms for analyzing the residual stresses in ground

components. • A deep understanding of the mechanisms of grinding-induced residual stresses with the full

coupling of mechanical loading, thermal cycle and phase transformation in workpieces. Status: On-Going Publications of this work: 1. M. Mahdi and L. Zhang, The finite element thermal analysis of grinding processes by

ADINA, Computers & Structures, 56 (1995) 313-320. 2. L. Zhang and M. Mahdi, Applied mechanics in grinding, Part IV: The mechanism of grinding

induced phase transformation, International Journal of Machine Tools and Manufacture, 35 (1995) 1397-1409

3. M. Mahdi and L. Zhang, Applied Mechanics in Grinding, Part V: Thermal residual stresses, International Journal of Machine Tools Manufacture, 37 (1997) 619-633.

4. M. Mahdi and L. Zhang, Applied Mechanics in Grinding: Part VI, residual stresses and surface hardening by coupled thermo-plasticity and phase transformation, International Journal of Machine Tools Manufacture, 38 (1998) 1289-1340.

5. M. Mahdi & L. Zhang, Residual Stresses in Ground Components Caused by coupled thermal and mechanical plastic deformation, Journal of Materials Processing Technology, 95 (1999) 238-245.

6. M. Mahdi and L. Zhang, Applied Mechanics in Grinding, Part VII: Residual stresses induced by the full coupling of mechanical deformation, thermal deformation and phase transformation, International Journal of Machine Tools & Manufacture, 39 (1999) 1285-1298.

94

7. M. Mahdi and L. Zhang, A Numerical Algorithm for the Full Coupling of Mechanical Deformation, Thermal Deformation and Phase Transformation in Surface Grinding, Computational Mechanics, 26 (2000) 157-165.

95

A10 Analytical and Experimental Investigation of Coolant Velocity in High Speed Grinding

Contact Information: Dr. Han Huang School of Mechanical Engineering University of Western Australia 35 Stirling Highway Crawley, WA 6009 Australia email: [email protected] Abstract : Use of water-base coolant is a pre-requisite in an high speed grinding process to avoid thermal damage and to achieve better surface integrity as well as higher grinding ratio. However, the presence of hazardous chemical additives in the coolant causes environmental problems. As a result, stringent government legislation is being practiced for the coolant use and disposal, which consumes 7-17% of the total machining cost. This research reports the coolant flux minimization through controlled jet impingement so as to prolong the coolant replenishment cycle. Control of coolant flux was achieved through development of a "metered quantity coolant" (MQC) nozzle which supplies the required amount of coolant to the grinding zone. Also, this investigation has shown that coolant velocity has a significant influence on the high speed grinding performance. When the coolant velocity is inadequate, coolant could not penetrate into the grinding zone. The increase in coolant velocity was realized with reduction in nozzle opening area and does not use a large quantity of coolant. This is of significance to reduce environmental pollution and machining costs through extended coolant replenishment period. The coolant velocity introduces lubrication effect at the grinding wheel-work interface that results in reducing force ratio from 0.56 to 0.38 and power-flux from 38 to 22 W/mm2. Furthermore, the surface finish was improved from 1 to 0.58 um with distinct plowing grooves and streaks. Key issues of the work: Status: Completed Publication of this work: K. Ramesh, H. Huang, and L. Yin, Analytical And Experimental Investigation Of Coolant Velocity In High Speed Grinding, Int. J. Machine Tools AND Manufacture, Vol. 44, No. 10, pp. 1069-1076.

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A11 High Speed and High Efficiency Grinding of Ceramics Contact Information: Dr. Han Huang School of Mechanical Engineering University of Western Australia 35 Stirling Highway Crawley, WA 6009 Australia email: [email protected] Abstract : This work aims at exploring material removal mechanisms involved in the high speed and high efficiency grinding processes. Machining characteristics and surface integrity of advanced ceramics have been studied under high speed deep grinding conditions. It was found that the material removal in the grinding of alumina and alumina–titania is dominated by grain dislodgement or lateral cracking along grain boundaries. The removal for zirconia is mainly via both local micro fracture and ductile cutting. The wheel depth of cut was increased to 2 mm. This increase did not deepen the subsurface damage layer for the alumina and alumina–titania, but resulted in a slightly deeper damage layer for the zirconia. Key issues of the work:

• Ductile grinding mechanisms of brittle materials • Coolant supply in high speed deep grinding

Status: on-going Publication of this work: 1.

2.

3.

4.

5.

H. Huang and Y.C. Liu, Experimental Investigations of Machining Characteristics and Removal Mechanisms of Advanced Ceramics in High Speed Deep Grinding, International Journal of Machine Tool and Manufacture, 43/8 (2003), 811-823. L. Yin and H. Huang, Ceramic Response to High Speed Grinding, Machining Science and Technology, 8/1 (2004), 21-37. L. Yin, H. Huang, K. Ramesh, T. Huang, High Speed versus Conventional Grinding in High Removal Rate Machining of Alumina and Alumina-Titania, International Journal of Machine Tools and Manufacture, 2004. (accepted) H. Huang, L. Yin and L. Zhou, High Speed Grinding of Silicon Nitride with Resin Bond Diamond Wheels, Journal of Materials Processing Technology, 141 (2003), 329-336. H. Huang, Effects of Truing/Dressing Intensity on Truing/Dressing Efficiency and Grinding Performance of Vitrified Diamond Wheels, Journal of Materials Processing Technology, 117 (2001), 9-14.

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A12 Nano/Micro Grinding Mechanisms and Technologies for Brittle Materials Contact Information: Dr. Han Huang School of Mechanical Engineering University of Western Australia 35 Stirling Highway Crawley, WA 6009 Australia email: [email protected] Abstract : The aims of the project are to investigate the fundamental mechanisms of deformation and removal of brittle materials in nano/micro grinding and to develop the pragmatic nano/micro grinding technologies for those materials. In particular, we aim at one-step grinding of micro aspherical mould inserts. Key issues of the work:

• Truing and dressing of micro grinding wheels • Ductile grinding mechanisms of brittle materials • Form error compensation

Status: on-going Publication of this work: 1.

2.

3.

4.

H. Huang, W.K. Chen, L. Yin, Z.J. Xiong, Y.C. Liu and P.L. Teo, Micro/Meso Ultra Precision Grinding of Fibre Optic Connectors and its Influence on Optic Performance, Precision Engineering: Journal of the International Societies for Precision Engineering and Nanotechnology, 28 (2004), 95-105. W.K. Chen, T. Kuriyagawa, H. Huang, H. Ono, M. Saeki, K. Syoji, A Novel Form Error Compensation Technique for Tungsten Carbide Mould Insert Machining Utilizing Parallel Grinding Technology, Key Engineering Materials, 257-8 (2004), 141-146. W.K. Chen, H. Huang and L. Yin, Loose Abrasive Truing and Dressing of Resin Bond Diamond Wheels for Grinding Fibre Optic Connectors, Journal of Materials Processing Technology. (in press) W.K. Chen, T. Kuriyagawa, H. Huang and N. Yosihara, Machining of Micro Aspherical Mould Inserts, Precision Engineering: Journal of the International Societies for Precision Engineering and Nanotechnology. (accepted)

98

AUSTRIA

99

AU1 Grinding of Non-circular Contours on Cylindrical Grinding Machines Contact Information: Univ.Prof.Dipl.-Ing.Dr. Adolf Frank Institut für Fertigungstechnik TU Graz Kopernikusgasse 24 A-8010 Graz, Austria Tel.: +43 316 873 7170 Fax: +43 316 873 7178 Email: [email protected] homepage: www.ift.tugraz.at Abstract: Grinding of non-circular contours on cylindrical grinding machines has a long tradition in Graz, which can be dated back to the fifties and the development of the famous Fortuna Polygon Grinder by Austrian Prof. Musyl, who was head of institute at Graz University of Technology. Todays research is focused on CNC non circular grinding on CNC cylindrical grinders. Examples of this type of grinding are camshafts. The equipment at the institution consists of a Fortuna Polygon, a Fortuna FM43CNC and a Kellenberger Vario175CNC grinding machine. Development of CNC programs for various controls and grinding machines for nearly any cross section, path optimization and standardization, has been critical for the project. The application of grinding camshafts and polygons according to standards DIN 32711 and DIN 32712 is offered as service to industry. Key Issues of the Work: • CNC camshaft grinding. • CNC grinding of Polygon profiles for shaft to hub connections. • Development of new standards for polygon profiles. • Development of CNC codes for non circular grinding Status: Ongoing Publications of this work: 1. C. Patzig, and W. Ortmayr, Precision Contour Grinding with Cylindrical Grinding Machines,

1st Int. Conference of Euspen, 1999, Bremen, Germany, pp.274-277. 2. Frank A. Schmid A., Grinding of non-circular contours on CNC cylindrical grinding

machines, Robotics & Computer-integrated Manufacturing. Vol. 4, No 1/2, pp.211-218, 1988. 3. Frank A., et al, Vom K-Profil und Polygonprofil zu funktionsoptimierten Unrundprofilen -

eine oesterreichische Entwicklung. praezision im spiegel, Herbst 1992, p.42-48. 4. Mayr R. Numerisch gesteuert kegelige Polygonprofile fertigen. Werkstatt und Betrieb 123

(1990) 9, pp.697-701. 5. Mayr R. Formschluessige Welle-Nabe-Verbindungen mit innenschleifbarer Kontur, PhD

Thesis, TU Graz 1993.

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BELGIUM

101

BE1 Robot Based Force Controlled High Efficiency Deep Grinding Contact Information: Professor Dr. Ir. Bert Lauwers K.U.Leuven – Division PMA Celestijnenlaan 300B B-3001 Heverlee (Belgium) Email: [email protected] http:www.mech.kuleuven.ac.be/pma Abstract: Within today casting industries, fettling and finishing of complex shaped castings is still a major cost element and is often manually performed. This research has been performed within the EU project Autofett (EU Project no. GRD1-200-25135) which aimed the development of an affordable and flexible system for the automated fettling and finishing of medium/large castings (up to 1500 kg) made in small numbers. Robot based force controlled grinding has been selected as the process to finish the stubs after removing the feeders and risers by robot based oxy fuel cutting. A 20 KW hydraulic grinding end-effector has been developed and mounted via a force sensor on an industrial robot.

Process models, describing the relation between material removal rate, surface quality and the process parameters set (force, feed rate,…) have been developed. Various stub grinding experiments have been peformed on casted blocks made of steel ASTM A216 WCB. Different cup-stones with varying composition and characteristics have been investigated. The influence of the applied force (up to 600N), feed rate (up to 70mm/min) and spindle speed (up to 5000 rpm) on the material removal rate and surface quality has been studied. Avoidance of chatter (due to the use of un-stiff robots) and avoidance of burning marks (due to the high power) were important topics to be taken into account. Key Issues of the Work: • Detailed study of the robot based force controlled stub grinding process • Development of process models Status: • Eu-project Autofett finished • Intentions to continue the research in the frame of other projects. Publications of this work: 1. B. Lauwers, H. De Baerdemaeker, Force controlled stub-grinding: development of process

technology, internal report, EU project Autofett, project nr. GRD1-2000-25135, April 2004. 2. Publications: others in preparation

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BE2 Grinding of Fibre Reinforced Plastics Contact Information: Peter Perremans WTCM-CRIF Wetenschapspark 9 B-3590 Diepenbeek Belgium Tel: +32 11 85 91 80 Fax: +32 11 22 92 90 Email: [email protected] http:www.wtcm.be Abstract: The research deals with the grinding of fiber reinforced plastic components for an industrial company. The tolerance requirements are rather high for plastic components (flatness and parallelism of 5 micron). The project is still going on and for the moment we are not allowed to publish the results so far. Key Issues of the Work: • Selection of optimal grinding materials • Optimization of grinding process Status: On going Publications of this work: • None

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BRAZIL

104

B1 Analysis Of Surface Integrity Using Minimum Quantity Lubricant – MQL In Grinding

Contact Information: Leonardo Roberto da Silva 1 Department of Mechanical Eng. CEFET, Belo Horizonte Av. Amazonas, 5253 Jd. Nova Suíça, CEP: 30480-000 MG, Brazil, email: [email protected], , Phone: +55-14-3103 6119 Abstract: The quality of machined components is currently under strong debate, for the market demands mechanical components of increasingly high efficiency, not only from the standpoint of functionality but also from that of safety. Components produced through operations involving the removal of material display surface irregularities resulting not only from the action of the tool itself, but also from other factors that contribute to their superficial texture. This texture can exert a decisive influence on the application and performance of the machined component. This article analyzes the behavior of the MQL technique and compares it with the conventional cooling method. To this end, an optimized fluid application method was devised using a specially created nozzle through which a minimum amount of oil is sprayed in a compressed air flow, thus meeting environmental requirements. This paper, therefore, explores and discusses the concept of the minimum quantity of lubricant (MQL) in the grinding process. The performance of the MQL technique in the grinding process was evaluated based on an analysis of the surface integrity (roughness, residual stress, microstructure and microhardness). The results presented here are expected to lead to technological and ecological gains in the grinding process using MQL. Key Issues of the Work: Status: Ongoing Publications of this work: None offered

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B2 Analysis of the Application of the Minimum Quantity Lubricant - MQL Technique in the Grinding Process

Contact Information: Leonardo Roberto da Silva 1 Department of Mechanical Eng. CEFET, Belo Horizonte Av. Amazonas, 5253 Jd. Nova Suíça, CEP: 30480-000 MG, Brazil, email: [email protected]: [email protected], Phone: +55-14-3103 6119 Abstract: Conventional cutting fluids used in machining processes are problematic for manufacturers, since they pose serious health hazards to human health and to the environment. Environmental issues have become increasingly important in productive processes, ranking on a par with economic and technological aspects. This work therefore focuses on the concept of minimum quantity of lubricant (MQL) in the grinding process. This technique has already been used successfully for many years in a variety of cutting processes. The grinding process involves several input parameters but, so far, little attention has been dedicated to the form and amount of cutting fluid applied in the process. The work reported on here involved an analysis of the behavior of the MQL technique, and the development of an optimized fluid application methodology consisting of a special nozzle through which a minimal amount of lubricant is pulverized through a compressed air flow. The evaluation of the performance of the MQL technique in grinding consisted of analyzing the behavior of the tangential cutting force, specific energy, G-ratio and roughness. It is expected that the results presented here will lead to technological and ecological gains in the grinding process using MQL. Key Issues of the Work: Status: Ongoing Publications of this work: None offered

106



B3 Computational Tools for Automatic Selection of Passes in Surface Grinding Process Contact Information: F. R. L. Dotto Laboratory of Data Acquisition and Signal Processing Department of Electrical Engineering São Paulo State University – UNESP Bauru, SP, Brazil, CP 473 CEP 17033-360 Tel: +55-14-2216115 E-mail: [email protected] Abstract: The main purpose of this work is the development of computational tools in order to aid the burning on-line automatic detection in the surface grinding process. Most of the parameters currently employed in the burning recognition (DPO, FKS, DPKS, DIFP, among others) do not incorporate routines for the passes automatic selection, therefore requiring the user’s interference for the choice of the active region. Several methods were employed in the passes extraction, however, those, which obtained the best results are presented in this article. Key Issues of the Work: Status: Ongoing Publications of this work: None offered

107


B4 Study Of Thresholds To Burning In Surface Grinding Process Contact Information: F. R. L. Dotto Laboratory of Data Acquisition and Signal Processing Department of Electrical Engineering São Paulo State University – UNESP Bauru, SP, Brazil, CP 473 CEP 17033-360 Tel: +55-14-2216115 E-mail: [email protected] Abstract: This work aims at finding out the threshold to burning in surface grinding process. Acoustic emission and electric power signals are acquired from an analog-digital converter and processed through algorithms in order to generate a control signal to inform the operator or interrupt the process in the case of burning occurrence. The thresholds that dictate the situation of burn and non-burn were studied as well as a comparison between the DPO and FKS parameters was carried out. In the experimental work one type of steel (ABNT-1045 annealed) and a TARGA Seeded Gel 3TG80.3 – NV grinding wheel were employed. Key Issues of the Work: Status: Ongoing Publications of this work: None offered

108


B5 Disturbances in Machining Operations: Microorganisms in the Cutting Fluid Contact Information: Eduardo Carlos Bianchi Department of Mechanical Engineering UNESP – Universidade Estadual Paulista Av. Eng. Luiz Edmundo Carrijo Coube, s/no Vargem Limpa, CEP 17033-360, Bauru, SP, Brazil. Phone: +55-14-2216119 E-mail: [email protected] Abstract: With the great increase in machining process, actually much more cutting fluid has been used to lubricate and cooling workpieces, however, the cutting fluid disposal is an expensive and illicit process when in disagreement with the Brazilian Environmental Laws. The microorganisms proliferation cause the useful life decreasing and the premature cutting fluid disposal. The goal of this paper is to present a bibliography review of several quantitative aspects of the cutting fluid microorganism proliferation, to show the main bacteria that degrade the cutting fluid and the consequence caused by the action, also showing several methods to preserve the cutting fluid. Key Issues of the Work: Status: Ongoing Publications of this work: None offered

109


B6 Analysis of the Cutting Fluid Influence on the Deep Grinding Process With CBN Grinding Wheel

Contact Information: Eduardo Carlos Bianchi Department of Mechanical Engineering UNESP – Universidade Estadual Paulista Av. Eng. Luiz Edmundo Carrijo Coube, s/no Vargem Limpa, CEP 17033-360, Bauru, SP, Brazil. Phone: +55-14-2216119 E-mail: [email protected] Abstract: The application of cutting fluid in a deep grinding process is becoming more and more important, mainly where the cutting fluids are used as an “external” agent to the grinding conditions. The role of the fluid in grinding operations is refrigerating the workpiece, to remove the shavings, to lubricate the grinding zone, to refrigerate and to clean the wheel. The efficiency of a cutting fluid will depend mainly of the type of fluid that will be used. In this work will be analyzed the influences of the type of cutting fluid used in a deep grinding process of the steel VC131 using CBN grinding wheel. Were used three different types of cutting fluids: a vegetable emulsion, a synthetic solution and a neat oil. The variables analyzed during and after the grinding process were the grinding force, the superficial roughness, the acoustic emission (EA), the temperature of the piece and the G ratio (relation between the volume of material removed of piece and the volume worn of grinding wheel). The neat oil showed the best performance with relation to the following output variables: EA, cutting force and G ratio. The vegetal emulsion was the fluid that best dissipated heat from the cutting region. Key Issues of the Work: Status: Ongoing Publications of this work: None offered

110


B7 Analysis of the Performance of Superabrasive and Conventional Grinding Wheels with Different Bonds and Machining Conditions

Contact Information: Eduardo Carlos Bianchi Department of Mechanical Engineering UNESP – Universidade Estadual Paulista Av. Eng. Luiz Edmundo Carrijo Coube, s/no Vargem Limpa, CEP 17033-360, Bauru, SP, Brazil. Phone: +55-14-2216119 E-mail: [email protected] Abstract: This paper presents a bibliographic review of research on CBN (cubic boron nitride) grinding wheels, with the purpose of identifying the current state of abrasive machining and to serve as the basis for future research to be carried out through laboratory tests. The scientific studies investigated here report on interesting results involving machining, published by Brazilian and foreign authors. The methods used and results obtained by several authors are described and discussed. In addition, a discussion is presented on the development of a setup that provides more reliable experimental results about the surface integrity of fragile materials machined with superabrasive CBN grinding wheels using resin bonds, and high performance and vitrified resin, and with conventional grinding wheels, subjected to a variety of machining conditions during the service life of this abrasive tool. The results of tangential cutting force, surface roughness of the part, and the G ratio are presented and discussed. These results reveal that the excellent machining capacity of the CBN grinding wheel, its tangential cutting force and the surface roughness of the machined part remained stable throughout the tests and that the G ratio values were compatible with those found internationally. Key Issues of the Work: Status: Ongoing Publications of this work: None offered

111


B8 Analysis Of The Different Forms Of Application And Types Of Cutting Fluid Used In Plunge Cylindrical Grinding Using Conventional And Superabrasive CBN Grinding Wheels

Contact Information: Eduardo Carlos Bianchi Department of Mechanical Engineering UNESP – Universidade Estadual Paulista Av. Eng. Luiz Edmundo Carrijo Coube, s/no Vargem Limpa, CEP 17033-360, Bauru, SP, Brazil. Phone: +55-14-2216119 E-mail: [email protected] Abstract: The work reported here involved an investigation into the grinding process, one of the last finishing processes carried out on a production line. Although several input parameters are involved in this process, attention today focuses strongly on the form and amount of cutting fluid employed, since these substances may be seriously pernicious to human health and to the environment, and involve high purchasing and maintenance costs when utilized and stored incorrectly. The type and amount of cutting fluid used directly affect some of the main output variables of the grinding process which are analyzed here, such as tangential cutting force, specific grinding energy, acoustic emissions, diametrical wear, roughness, residual stress and scanning electron microscopy. To analyze the influence of these variables, an optimized fluid application methodology was developed (involving rounded 5mm, 4mm and 3mm diameter nozzles and high fluid application pressures) to reduce the amount of fluid used in the grinding process and improve its performance in comparison with the conventional fluid application method (of diffuser nozzles and lower fluid application pressure). To this end, two types of cutting fluid (a 5% synthetic emulsion and whole oil) and two abrasive tools (an aluminum oxide and a superabrasive CBN grinding wheel) were used. The results revealed that, in every situation, the optimized application of cutting fluid significantly improved the efficiency of the process, particularly the combined use of whole oil and CBN grinding wheel. Key Issues of the Work: Status: Ongoing Publications of this work: None offered

112


B9 Correlating Surface Roughness and Vibration in Plunge Cylindrical Grinding of Steel Contact Information: Prof. Dr. Anselmo Eduardo Diniz DEF/FEM/UNICAMP - CP 6122 Campinas - SP - 13083-860, Brazil. Phone number - 55-19-37883303 Fax number - 55-19-32893722 e-mail address: [email protected] website: http://fit.fem.unicamp.br/hpinst/docentes/docentes.html Abstract: The wear of a grinding wheel has a direct effect on the workpiece vibration and both have effect on the workpiece quality, the main goal of this work is to study the relation between the process vibration signals and the workpiece quality (mean roughness, circularity and burning) as the grinding wheel gets worn, in an attempt to use these signals to decide the exact moment to dress the wheel. In order to reach this goal, several experiments were carried out in a plunge cylindrical grinding operation of an AISI 52100 quenched and tempered steel, having as input variables the dressing overlap ratio, the spark-out time and the workpiece velocity. The output variables were the workpiece surface roughness and circularity and also the process vibration during both, the cutting phase and the spark out phase of the grinding cycle. The main conclusions were: it is possible to have good workpiece quality even with a vibration level much higher than that obtained with a recently dressed wheel; vibration during cutting phase and at the end of complete spark-out can be used to monitor the wheel condition at least when high dressing overlap ratio is used; the decrease in the spark out time makes the vibration at the end of spark out increase a lot, but does not cause such a damage in surface roughness. This fact makes the use of partial spark-out feasible in some situations. Key Issues of the Work: • The loss of dressing macro effect makes roughness decrease and vibration increase; • The loss of dressing micro effect makes both, vibration and roughness increase, but the

former increases much more than the later; • Vibration during cutting phase and at the end of complete spark out can be used to monitor

the wheel condition and, consequently, its consequence on the workpiece in terms of surface roughness at least when high Ud is used. When low Ud is used, vibration follows roughness just when the amount of chip removed per unit of time (or vw) is high.

Status: Ongoing Publications of this work: 1. Hassui, A., Diniz, A. E., Oliveira, J. F. G., Felipe Jr, J., Gomes, J. J. F., Experimental

Evaluation on Grinding Wheel Wear Through Vibration and Acoustic Emission. WEAR, v. 217, pp. 7-14, 1998.

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http://fit.fem.unicamp.br/hpinst/docentes/docentes.html

2. Hassui, A. and Diniz, A. E., Correlating surface roughness and vibration in plunge cylindrical grinding of steel, Int. Journal of Mach. Tools and Manufacture, 43(2003) 855-862.

114

B10 Fast Grinding Process Control with AE Modulated Power Signals Contact Information: Professor Joao Oliveira Nucleus for Adavanced Manufacturing University of São Paulo, SP, Brazil Email: [email protected] http:www.opf.sc.usp.br Abstract: Process reliability and tool costs are becoming more important with the growing application of CBN wheels in grinding. Despite the availability of a wide range of sensors for monitoring of grinding operations, there is still a need for a control parameter that is fast enough to detect short process variations and reliable enough to represent the grinding energy. Power and acoustic emission (AE) signals are among the most commonly used for process monitoring and control. The power, which is approximately proportional to the stock removal rate in grinding, is usually obtained by measurement of electric current and voltage at the wheel spindle motor. While this method is robust and easy to apply, it is limited by its relatively slow response. On the other hand, the AE information presents an extremely fast and consistent local response, but its root mean square (RMS) level has no deterministic correlation with the grinding power. In this work, a new sensor fusion method is introduced to improve the performance of a power and AE based monitoring and control system. This new method, called Fast Abrasive Power (FAP), combines conventional power monitoring with AE to obtain a robust and fast power measurement. FAP is achieved through the modulation of the original power signal by the normalized AE RMS dynamics. Some main characteristics of the FAP method are: the set-up cost is much lower than a piezo-dynamometer; easy installation; low sensitivity to AE gain variations; insensitive to AE fluctuations (if the fluctuations occur out of the time window tw); the dynamic response can be adjusted to the monitoring requirements by changing tw, k and the RMS time constant. Key Issues of the Work: • Develop a signal able to reliably monitor fast grinding cycles. • To improve closed loop control on grinding and robotic deburring.. Status: On-going Publications of this work: 1. Oliveira, J. F. G., Valente, Carlos Magno De Oliveira, Fast Grinding Process Control With

Ae Modulated Power Signals. Annals of CIRP 2004. Krakow - Polônia: , V.53, N.01, P.267 - 270, 2004.

2. Valente, Carlos Magno De Oliveira., Oliveira, J. F. G., Fast Abrasive Energy: A New Way To Control Robots On Deburring Operation. Abrasives Magazine. Estados Unidos: , V.2001, N.04, P.12 - 23, 2001.

115

B11 A New Concept of Grinding Fluid Contact Information: Professor Joao Oliveira Nucleus for Adavanced Manufacturing University of São Paulo, SP Brazil Email: [email protected] http:www.opf.sc.usp.br Abstract: The grinding process is highly used in the finishing of precision mechanical components. There has been a high demand for better adequacy of these industrial grinding processes in order to meet the present requirements of safety and protection to the environment. In this scenario new combinations of fluids and grinding wheels have been tested in research projects. The application of grinding wheels using Cubic Boron Nitrite (CBN) abrasives is a strong tendency in grinding processes. These tools allow better product quality and higher heat transfer from the cutting area due to its high thermal conductivity and low coefficient of friction. On the other hand these tools are very costly when applied with water base coolants due to the excessive wear. The better performance of CBN is achieved when mineral neat oils are used. This happen due to the high lubricity of the mineral oil. There is a need of an environmentally friendly fluid with high lubricity for the application in CBN grinding. An environmentally friendly fluid has to accomplish some main requirements such as: should not be toxic, biodegradable and should produce low emissions. It has also to provide good process performance and allow low costs in the application of CBN based tools. This work presents new grinding fluid formulation able to meet both the performance and environmental requirements. The proposed fluid is based on a sulfonate vegetable oil with high concentration in water. This way it is possible to get high lubricity and good performance on CBN grinding. The tests show that the application of the proposed formula in CBN grinding results in process performance equivalent to the obtained using mineral neat oils. Chemical analysis shows the new fluid as to be non-toxic and have easy biodegradability. Key Issues of the Work: • Reduce the impacts to environment through a vegetable based coolant. • Increase grinding performance with a coolant with both high thermal conductivity and

lubricity. Status: On-going Publications of this work: Oliveira, J. F. G., Alves, Salete Martins, Precision CBN Grinding Process Adequacy Through a New Concept of Grinding Fluid in: Global Conference on Sustainable Product Development and Life Cycle Engineering, 2004, Berlin. Gmbh, 2004. V.01. P.39 - 44

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B12 Development of a Grinding System for the Crankshaft High Speed Grinding using CBN Wheels

Contact Information: Professor Joao Oliveira Nucleus for Adavanced Manufacturing University of São Paulo, SP, Brazil Email: [email protected] http:www.opf.sc.usp.br Abstract: The aim of this research is the development of a grinding system to be applied in the crankshaft high speed grinding using CBN wheels. The system was installed in a specially developed high-speed CBN grind machine, which contains the most important features to efficiently grind in high speed. An open architecture CNC installed in the machine permits the two-way CNC and PC communication by a High-speed Serial Bus (HSSB). Monitoring and controlling systems were installed under a user-defined HMI interface which combines the CNC operational software and intelligent grinding routines developed by the OPF group, such as anti-collision, gap less, and the acoustic mapping of the grinding wheel surface. A dressing system for profiled vitrified CBN wheel was developed in order to obtain a high efficient dressing operation. Using an electric drive unit and an electroplated diamond disc, two dressing configurations were tested: cross axis and parallel axis dressing. In order to ensure the full dresser/wheel contact during the dressing operation, the acoustic emission was used to capture and update the dresser coordinates before each dressing, avoiding thermal deviations. The acoustic mapping of the wheel surface was used to evaluate the dressing operation. The best results were obtained using the parallel configuration. The cutting fluid application system was also improved. The best results were obtained when two efficient nozzle designs were used together: (shoe nozzle and coherent jet nozzle). The crankshaft grinding operation was reproduced using test specimens with the same crankshaft main bearing geometry. Two different grinding strategies were tested: the traditional approach (plunge grinding) and the proposed strategy (face grinding). The obtained results indicate that the total grinding time can be reduced when the proposed strategy is used. Comparative lifetime grinding tests will be performed and the wheel wear (especially in the wheel corners) will be evaluated. A grinding model is being developed in order to determine the kinematics interactions during the bearing face grinding (radius, shoulder and diameter), and to determine the best grinding strategy to be applied. As a result, the final version of the grinding system will incorporate monitoring and controlling systems combined with the most suitable dressing and cutting fluid application and grinding strategies for high speed CBN crankshaft grinding. The partners of this research are FAPESP (Grant # 00/10199-9), CNPq SWE 201040/03-4, ZEMA, GE-FANUC, SAINT-GOBAIN, MICRO QUIMICA, AÇOS VILLARES; WZL-RWTH. Key Issues of the Work: • Develop new grinding strategies for the production of crankshaft shoulders. • Develop grinding monitoring solution. • Improve quality and productivity in the manufacturing of crankshafts.

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Status: On-going Publications of this work: 1. Silva, Eraldo Jannone Da; Biffi, Marcelo; Oliveira, João Fernando Gomes De., The

Development Of An Open Architecture Control System For CBN High Speed Grinding., Journal Of The Brazilian Society Of Mechanical Sciences, Brasil, V. Xxvi, N. 01, P. 51-55, 2004.

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B13 Software Based Analysis of Acoustic Emission Maps in the Grinding Operation Contact Information: Professor Joao Oliveira Nucleus for Adavanced Manufacturing University of São Paulo, SP, Brazil Email: [email protected] http:www.opf.sc.usp.br Abstract: The grinding operation can be considered one of the most important processes in manufacturing, as it is a highly complex operation that works pieces with a high aggregate value. Thus, a monitoring system for the grinding operation is an important solution that can lead to greater reliability and greater piece quality. There are various sensors that can be used in the grinding process. The acoustic emission sensor is characterized by its ability to detect most known problems, in operations of low and high precision. It is used to generate a graphic, called acoustic emission map, which allows us do diagnose several types of problems, through the presence of vertical, horizontal or diagonal patterns. Among these problems are: unbalanced wheel, grinding chatter and unregulated wheel eccentricity. A real time data acquisition system that creates an acoustic emission map, based in the Labview software, was used. This map is sent to another computer, through a protocol called DataSocket, which is based on TCP/IP, where it is interpreted by a software created with C++. This software detects the patterns that characterize the different problems in the process. As the data acquisition software overloads a single computer, the distribution of computation was a necessity to this system. This distribution of computational power can be utilized in other systems, as it allows for more computational power and can use the computation resources that are not usually used - e.g., microcomputers that only run Office applications. Key Issues of the Work: • Help the diagnosis of grinding issues related to the energy distribution around the wheel. • Monitoring of grinding and dressing for cycle time reduction • Improve quality and productivity in grinding. Status: On-going Publications of this work: 1. Vieira, Jalon de Morais., Oliveira, J. F. G., Monitoring of Plunge Centerless Grinding

through Acoustic Emission. Abrasives Magazine, V.2002, N.01, P.15 - 19, 2002. 2. Oliveira, J. F. G., Dornfeld, D. A., Application of AE Contact Sensing in Reliable Grinding

Monitoring, Manufacturing Technology Annals of The CIRP, Berne, Switzerland: , V.51, N.1, P.217 - 220, 2001.

3. Oliveira, J. F. G., Coelho, Reginaldo Teixeira, Tundisi, José Eduardo M, Gomes, João Jorge De Faria, Bellini, P. H. C., A New System to get Information about the Grinding Wheel Performance.. Abrasives Magazine. Estados Unidos:, V.2000, N.03, P.24 - 30, 2000.

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4. Oliveira, J. F. G., Dornfeld, D. A., Winter, B., Dimensional Characterization of Grinding Wheel Surface through Acoustic Emission.. Manufacturing Technology Annals of the CIRP. Berne, Suiça: , V.44, N.1, P.291 - 294, 1994.

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B14 Lubrication of the Grinding Process Contact Information: Professor Amauri Hassui Department of Mechatronics and Mechanical Systems Engineering Escola Politécnica of the University of São Paulo Prof. Mello Moraes Avenue, 2231 São Paulo - SP - 05508-900 Brazil Tel: +55 11 3091 9718 Fax: +55 11 3091 5461 Email: [email protected] http: Abstract: This researcher is testing different ways of lubricating the plunge grinding process. The input variables are lubricating flow and type. The goal to be reach is achieve a cheaper and more ecological way of grinding without damage the workpiece integrity. Key Issues of the Work: • Keep the grinding temperature as low as possible lubricating the process instead of cooling it Status: Started in 2004 Publications of this work: Nothing yet

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B15 Monitoring of the Grinding Process Using Vibration Sensors Contact Information: Professor Amauri Hassui Department of Mechatronics and Mechanical Systems Engineering Escola Politécnica of the University of São Paulo Prof. Mello Moraes Avenue, 2231 São Paulo - SP - 05508-900 Brazil Tel: +55 11 3091 9718 Fax: +55 11 3091 5461 Email: [email protected] http: Abstract: This researcher has monitored cylindrical plunge grinding using vibration sensors. It was monitored the cutting and spark out. It was found that vibration sensors can determine the end of grinding wheel life when the dressing is fine. Both the cutting and spark out phase vibration were related with the workpiece roughness. Key Issues of the Work: • Analysis of the spark out phase using vibration signals Status: Completed 2001 Publications of this work: 1.

2.

Hassui, A., Diniz, A. E. Correlating Surface Roughness and Vibration in Plunge Cylindrical Grinding of Steel. International Journal of Machine Tools and Manufacture: , v.43, p.855 - 862, 2003. Hassui, A., Diniz, A. E., Oliveira, J. F. G., Felipe Jr, J., Faria, J. J. G.,Experimental Evaluation on Grinding Wheel Wear Through Vibration and Acoustic Emission. Wear: , v.217, p.7 - 14, 1998

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B16 The Evolution of the MMKS Systems: Automation Brings Growth to the System´s Efficiency through the use of Lubrication Strategies

Contact Information: Prof. Dr.-Ing. Walter Lindolfo Weingaertner

Laboratory of Precision Engineering Federal University of Santa Catarina Mechanic’s Engineers Department Caixa Postal: 476 – EMC Florianópolis/SC CEP: 88.010-970 Brazil E-mail: [email protected] Abstract: The minimal quantities of cutting fluids systems applied in machining and grinding operations are a technological development motivated by new and severe environmental and workers’ protections laws. Those systems lubricate the cutting tool with a spray, formed with compressed air and a lubricant fluid injected in very small quantities (10 to 100 ml/h). The spray is created in a special nozzle, where the fluid is sprinkled by the flux of compressed air. One of the main advantages of this lubricating method is that there is no need of treatment for the machining wastes, reducing the costs related with the cutting fluid to an irrelevant faction of the total machining costs. Meanwhile, the minimal quantities of cutting fluids systems available present some difficulties in the application in the milling and grinding operations: the command of the nozzles is strongly connected to the machine-tool operator and, due to the nozzles position and the motion characteristics of the cutting tool, the lubrication is frequently made with a low efficacy. The technological development of the minimal quantities of cutting fluids systems goes across the implementation of automated command systems to the nozzles and their use with special features, that guarantee a good quality in the lubrication of the cutting tool under the variety of the cutting strategies within the milling and grinding operations. Status: Ongoing Publications of this work: Weingartner, W.L., Pinto, F.W. The evolution of the MQCF systems: automation brings growth to the system´s efficiency through the use of lubrification strategies In: 17th ICPR - International Conference on Production Research v.1, pp. 1 - 10 2003 Blacksburg - Virginia - USA. [s.n], 2003.

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CANADA

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CA1 Development of an Automated System to Evaluate the Surface Condition of Grinding Wheels in Surface Grinding Contact Information: Robert Bauer Associate Professor Department of Mechanical Engineering Dalhousie University Halifax, NS Canada Tel: (902) 494-3942 Email: [email protected] Abstract: In this research a new system to measure wear flat area is developed. This system is mounted on the grinding machine and automates the measurement process by using computer control to automatically position the wheel and capture digital images of the wheel between grinding cycles. Image processing software is then used to analyze the digital images and measure the wear flat area. The proposed measurement system was validated using a Scanning Electron Microscope. Key Issues of the Work: -image processing -automation of wear flat area measurement Status: Completed 2004 Publications of this work: 1. Lachance, S., Bauer, R.J., Warkentin, A., “Application of Region Growing Method to

Evaluate the Surface Condition of Grinding Wheels”, International Journal of Machine Tools and Manufacture, Vol. 44, 2004, pp. 823-829.

2. Lachance, S., Warkentin, A., Bauer, R.J., “Development of an Automated System for Measuring Grinding Wheel Wear Flats”, Journal of Manufacturing Systems, Vol. 22, No. 2, 2003, pp 130-135.

3. Lachance, S., Warkentin, A., Bauer, R., “Development of an Automated System for Measuring Grinding Wheel Wear Flats”, Proceedings of the 31st North American Manufacturing Research Conference, McMaster University, Hamilton, Ontario, 2003.

4. Lachance, S., Bauer, R., Warkentin, A., “Automated Grinding Wheel Wear Measurement from Digital Images”, Proceedings of the 19th Canadian Congress of Applied Mechanics, University of Calgary, Alberta, 2003.

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CA2 EDM-grinding Hybrid Processes. Contact Information: Professor Philip Koshy Department of Mechanical Engineering McMaster University Hamilton, Ontario, L8S 4L7, Canada Email: [email protected] http: www.mech.mcmaster.ca Abstract: Hybrid machining techniques integrate two or more processes with a view to exploiting their synergy. The research pertains to the development of a hybrid process that combines electrical discharge machining (EDM) and grinding. The electrical spark discharges deployed in the grinding zone bring about thermal softening of the workpiece reducing grinding forces, and promote effective grinding through in-process wheel dressing and declogging. Key Issues of the Work: • Characterization of EDM-grinding hybrid process in the machining of difficult-to-grind

materials like polycrystalline diamond. Status: Completed Publications of this work: 1.

2.

P. Koshy, V.K. Jain, G.K. Lal. Grinding of cemented carbide with electrical spark assistance, Journal of Materials Processing Technology 72 (1), 61-68 (1997). P. Koshy, V.K. Jain, G.K. Lal. Mechanism of material removal in electrical discharge diamond grinding, International Journal of Machine Tools and Manufacture 36 (10), 1173-1185 (1996).

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CA3 Novel Kinematics for Cylindrical Grinding of Brittle Materials. Contact Information: Professor Philip Koshy Department of Mechanical Engineering McMaster University Hamilton, Ontario, L8S 4L7, Canada Email: [email protected] http: www.mech.mcmaster.ca Abstract: Brittle materials are characterized by grinding direction related strength anisotropy attributed to the dual population of grinding induced microcracks. Surface grinding operations are therefore generally accomplished such that the grinding lay is along the direction of maximum tensile stress in the component, which corresponds to minimal strength degradation. The kinematic configuration of conventional machine tools inherently precludes such an approach in cylindrical traverse grinding. To this end, the work entails development of an innovative material-adapted kinematic variant that would facilitate enhanced material removal rates with the least detriment to strength. For the same grinding time, quartz rods ground in the novel configuration correspond to an enhancement of characteristic flexural strength on the order of 30% in comparison to conventionally ground samples. Key Issues of the Work: • Characterization of strength, roughness, roundness, and grinding forces in the novel

cylindrical grinding process vis-à-vis conventional traverse cylindrical grinding. • Fractography of ground samples. Status: On-going Publications of this work: 1. P. Koshy, Y. Zhou, C. Guo, R. Chand. Novel kinematics for cylindrical grinding of brittle

materials, submitted for publication in the Annals of CIRP (2005).

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CA4 Stochastic Simulation of Diamond Grinding Processes. Contact Information: Professor Philip Koshy Department of Mechanical Engineering McMaster University Hamilton, Ontario, L8S 4L7, Canada Email: [email protected] http: www.mech.mcmaster.ca Abstract: The research program relates to computer simulation of diamond grinding processes using stochastic three-dimensional wheel topography models. The work completed refers to surface finish issues. A model for predicting the roughness of diamond-ground surfaces with emphasis on process-inherent variability has been developed. This work has further been extended to formulate a theoretical framework for the design of engineered grinding wheels that comprise abrasives grains positioned in a specified spatial pattern as opposed to random locations in conventional diamond wheels. Current work is on the design of diamond grinding processes to optimize material removal rates, with reference to constraints associated with grinding damage. The key aspect of this research is the estimation of the distribution of the load acting on individual active grinding grits, which is a random variable. It is envisaged that the research would pave the way for cost-effective grinding of brittle materials. Key Issues of the Work: • Application of topography models to predict roughness, residual strength, temperature and

residual stresses in diamond grinding of brittle materials. Status: On-going Publications of this work: 1. P. Koshy, A. Iwasaki, M.A. Elbestawi. Surface generation with engineered grinding wheels:

Insights from simulation, Annals of CIRP, 52 (1), 271-274 (2003). 2. P. Koshy, L.K. Ives, S. Jahanmir. Simulation of diamond-ground surfaces, International

Journal of Machine Tools and Manufacture 39 (9), 1451-1470 (1999). 3. P. Koshy, V.K. Jain, G.K. Lal. Stochastic simulation approach to modelling diamond wheel

topography, International Journal of Machine Tools and Manufacture 37 (6), 751-761 (1997). 4. P. Koshy, V.K. Jain, G.K. Lal. A model for the topography of diamond grinding wheels,

Wear 169 (2), 237-242 (1993).

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Title: High Speed Superabrasive (CBN) Grinding Processes Contact Information: Dr. Zhongde Shi/Dr. Helmi Attia Aerospace Manufacturing Technology Center (AMTC), National Research Council of Canada (NRC) McGill University 5145 Avenue Decelles Campus of University of Montreal Montreal, QC, H3T 2B2 Canada Email: [email protected] , or [email protected] http: www.nrcaerospace.com , or www.mcgill.ca/mecheng Abstract:

A research project is underway to investigate the temperature and residual stresses in high speed grinding of hardened steel and nodular cast iron using superabrasive (CBN) grinding wheels. High speed grinding which enables the use of high material removal rates is critical for enhancing overall productivity in industry. With the increase of wheel speeds, the grinding temperature and unfavorable residual stresses are expected to increase accordingly, which may cause workpiece burning and initiate cracks on the ground surface, respectively. The object of this research is to investigate the relationships between grinding parameters, temperature, and residual stresses.

Key Issues of the Work: • Modeling of residual stresses under high speed grinding conditions. Status: In process.

Publications of this Work: None so far

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Title: Modeling and Simulation of Grinding Processes with Vitrified CBN Wheels. Contact Information: Dr. Zhongde Shi/Dr. Helmi Attia Aerospace Manufacturing Technology Center (AMTC), National Research Council of Canada (NRC) McGill University 5145 Avenue Decelles Campus of University of Montreal Montreal, QC, H3T 2B2 Canada Email: [email protected] http: www.nrcaerospace.com Abstract: A research project is underway to investigate the grinding of hardened steel and nickel alloy with vitrified CBN wheels. This project encompasses modeling of grinding behavior and experimental verifications over a wide range of operating conditions, and the development of grinding simulation software. Upon completion of this project, quantitative models and grinding simulation software will be developed to predict grinding power and forces, surface roughness, and residual stresses and so on. This investigation will provide the analytical basis for optimizing grinding processes with vitrified CBN wheels.

Key Issues of the Work: • Modeling of grinding processes and calibration strategy for grinding models. Status: In process. Publications of this Work: None so far

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CHINA

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C1 MD Simulation in Nanometric Grinding Contact Information: Professor D.M.Guo, Professor R.K. Kang Key Laboratory for Precision & Non-traditional Machining Technology of Ministry of Education School of Mechanical Engineering Dalian University of Technology Dalian, 116024，P.R. China Phone: 86-411-84707430-806 E-mail: [email protected] Abstract: Molecular dynamics (MD) simulation is an effective microscopic approach to analyze the mechanism of nanometric machining from an atomistic viewpoint. Until today several applications of the method have been found dealing with indentation tests or cutting processes. Based on analyzing the development tendency of machining and the requirements of recent nanometric science and technology, the background and significance both in theoretical and practical aspects of MD simulation are illustrated. The scientific foundation, methods and basic steps of MD are presented. The authors established a grinding MD model according to the characteristics of the grinding process. The grinding process at an indentation depth of 1 silicon atomic layer is simulated. Key Issues of the Work: • Molecular dynamics modeling of grinding process Status: On-going Publications of this work: 1. R.K. Kang, X.G.Guo,D. M. Guo, Z.J.Jin. Towards a deep understanding of MD simulation in

nanometric machining, Key Engineering Materials, 2003,Vols.259~260, pp. 216-220 2. R.K. Kang, X.G.Guo,D. M. Guo, Z.J.Jin. Study of MD simulation in nanometric grinding,

Key Engineering Materials, 2003,Vols.257~258, pp. 33-38

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C2 Ultra Precision Grinding of Hard and Brittle Materials Surface Integrity in Grinding Hard and Brittle Materials

Contact Information: Professor D.M.Guo, Professor R.K. Kang Key Laboratory for Precision & Non-traditional Machining Technology of Ministry of Education School of Mechanical Engineering Dalian University of Technology Dalian, 116024，P.R. China Phone: 86-411-84707430-806 E-mail: [email protected] Abstract: With faster developing of IC manufacturing technology, the diameter of wafer trends to be larger in order to increase the yields of chips and reduce the cost per bit, at the same time, the thickness of prime wafer is also increasing to ensure the strength of wafer. Contrarily, the chip thickness is decreasing to meet the requirements of IC package so that the backside thinning of pattern wafers is required. Thus, it is the increase of the material removal amount caused by size changes of wafer and chip and the higher requirements of precision and surface quality of wafer that make the traditional wafer processing technology face the challenge. Because of limitations of the traditional wafer processing technology, ultra precision grinding technologies is applied in processing and backside thinning of large diameter wafer in IC manufacturing process. A kinematics model of the wafer rotation grinding is developed, the cutting trajectories of grits on the silicon wafer are predicted by computer simulations based on the mathematical model, the relationship between grinding surface quality and the density of grinding marks is theoretically analyzed. The formula of material removal rate (MRR) in wafer rotation grinding process is deduced based on kinematics, the effects of the grit size and the process parameters, including the rotational speed of the cup grinding wheel, the down feed rate of the grinding wheel spindle and the rotational speed of the chuck table, on MRR are theoretically. The influences of the main process factors mentioned above on the MRR, spindle motor current and wafer surface roughness in grinding large size wafer are experimentally investigated, The results show that , when increasing the feed rate of the grinding wheel , decreasing the rotating speed of the wafer chuck table and using coarser grit grinding wheel , the MRR in the wafer rotating grinding increase , the feed rate of the grinding wheel has greater influence on the MRR; when suitably increasing the rotating speed of the grinding wheel , decreasing the feed rate of the grinding wheel and using finer grit grinding wheel , the wafer surface roughness can be reduced; there exists a critical rotating speed of the grinding wheel (about 2300rpm) , beyond which the MRR evidently decreases and the spindle motor current and wafer surface roughness steeply increase; when the grit size of the grinding wheel is finer than # 2000 , the MRR decreases and the wafer surface roughness is not improved obviously. Surface roughness, subsurface crack configuration, subsurface damage depth (SSD) and phase transformation induced in wafer rotation grinding are experimentally investigating and evaluated by corresponding methods. The results show that the ground wafer quality has a close relationship with the grit size. The surface roughness and the SSD increase with increasing of the grit size. The subsurface crack configurations of (100) silicon wafers are complicated. The

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material removal mechanism is different under different grinding conditions. Ductile grinding is accompanied by the phase transformations of diamond structure silicon. The amorphous silicon (α-Si), the Si-XII phase (r8-rhombohedral structure) and Si-III phase (bc8-body-centered cubic structure) exist on the wafer surface region after grinding by #600 and #2000 grinding wheels. Key Issues of the Work: • The ways of increasing material removal rate and decreasing surface roughness in grinding

silicon wafer • Detecting and controlling of surface and subsurface damage in grinding silicon wafer • Suitable selection of process parameters in grinding silicon wafer Status: On-going Publications of this work: 1. Y.B.Tian, R.K.Kang, D.M.Guo, Z.J.Jin, J.X.Su., 2004,Investigation On Material Removal

Rate In Rotation Grinding for Large-scale Silicon Wafer, Materials Science Forum, Vols.471~472,pp. 362-368.

2. R.K.Kang,Y.B.Tian,D.M.Guo,Z.J.Jin.,2003,Present status of research and application in ultra-precision grinding technology of large-scale silicon wafers, Diamond and Abrasives Engineering, No. 4, pp. 13-18

3. Y.B.Tian,D.M.Guo,R.K.Kang,Z.J.Jin.,2004,Grinding of large size silicon wafer on a wafer-rotating grinding machine, Diamond and Abrasives Engineering, No. 4, pp. 1-5

4. Y.B.Tian,D.M.Guo,R.K.Kang,Z.J.Jin.,2004,A Study on Kinematic Trajectory in Wafer Rotation Grinding, Proceedings of the 6th International Conference on Frontiers of Design and Manufacturing, Science Press and Science Press USA Inc.

5. Y.X.Zhang,R.K.Kang,D.M.Guo,Z.J.Jin.,2004,Surface/subsurface damage of ground monocrystalline silicon wafer,Proceedings of the 6th International Conference on Frontiers of Design and Manufacturing, Science Press and Science Press USA Inc.

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C3 Grinding Fluid for Superabrasive Grinding Wheels Contact Information: Professor R.K. Kang Key Laboratory for Precision & Non-traditional Machining Technology of Ministry of Education School of Mechanical Engineering Dalian University of Technology Dalian, 116024，P.R. China Phone: 86-411-84707430-806 E-mail: [email protected] Abstract: By comparison of the wear characteristics for a cubic boron nitride (CBN) grain and a conventional grains, and analysis for wear characteristics of the vitrified bonded CBN wheel, the effects of three kinds of grinding fluids on grinding performances of the vitrified bonded CBN wheel were studied. It is shown that the metal chips adhered to CBN grains cause the grinding force increase so as to lead to breaking of CBN grain and bonds. The effects of grinding fluid are to reduce friction and reject adherence. When the extreme pressure oil was used to grind the different materials, the grind reduced by 20-50%, grinding temperature lowered by 20-200°C and grinding ratio increased by a factor of 3-30 as compared with the synthetic water based fluid. Key Issues of the Work: • Influence of grinding fluid on the performances of superabrasive grinding wheels • Suitable selecting of grinding fluid in grinding difficult-to-cut materials with superabrasive

grinding wheels Status: On-going Publications of this work: 1. R.K.Kang, J.T. Yuan, J.X.Ren., 2000,Effect of grinding fluid on grinding properties of

vitrified bonded CBN wheel, Journal of Northwestern Polytechnical University, Vol.18, No. 4, , pp.527-531

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C4 Truing and Dressing of Superabrasive Grinding Contact Information: Professor R.K. Kang Key Laboratory for Precision & Non-traditional Machining Technology of Ministry of Education School of Mechanical Engineering Dalian University of Technology Dalian, 116024，P.R. China Phone: 86-411-84707430-806 E-mail: [email protected] Abstract: Studies on the methods of truing and dressing superabrasive grinding wheels by Nd: YAG laser were carried out,in which laser beam is focused onto superabrasive grinding wheel surface at tangential and normal direction respectively. The feasibility and principle of truing and dressing superabrasive grinding wheels by laser are theoretically discussed. By means of a SEM, the surface topography of both resin and bronze bonded diamond wheels after laser truing and dressing are observed, and also the collected chips from the diamond wheels during laser truing and dressing. The roundness variations of the diamond wheels after laser truing are measured by ues of a roundness instrument. It is shown that the expectant geometric shape and accuracy of the diamond wheels can be obtained after truing and the larger protruding high can be gained after dressing by controlling the laser irradiation parameters and the diamond wheel motions relative to laser beam, In laser truing and dressing, the resin bond materials are decomposed, the bronze bond materials are molten or vaporized, and diamond grains are less damaged. When truing the wheels, the repeated truing is available for further improving the surface topography and geometric accuracy of the diamond wheels if necessary. After the contrasting experiment of grinding Si3N4 ceramic, the results show that the diamond wheel after dressed by laser are better in grinding performances than one after dressed by other dressing method, such as GC grinding wheel dressing method.

Key Issues of the Work: • grinding performances of the superabrasive grinding wheels after laser truing and dressing • The selecting and controlling the laser irradiation parameters in laser truing and dressing Status: On-going Publications of this work: 1. R.K.Kang, J.T. Yuan, Y.P.Zhang,J.X.Ren., 2001, Truing of Diamond Wheels by Laser. Key

Engineering Materials,Vol.202~203,pp.137-142 2. R.K.Kang, J.T. Yuan, J.Lan,J.X.Ren., 2000, Study on laser dressing of superabrasive

grinding wheels. China Mechanical Engineering, Vol. 11, No. 5, pp. 493-496

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C5 Electrolytic In-processing Dressing (ELID) Mirror Grinding Contact Information: Professor D.M.Guo Key Laboratory for Precision & Non-traditional Machining Technology of Ministry of Education School of Mechanical Engineering Dalian University of Technology, Dalian, 116024，P. R. China, Phone: +86-411-84706059 Email: [email protected] Abstract:The Electrolytic In-processing Dressing (ELID) is successfully applied in precision mirror surface grinding and efficient processing of difficult and hard workpieces. The processing of hard and brittle materials by ELID grinding technology was found to produce high quality finished surfaces. Applying super-abrasive and metal-base wheel, the ELID grinding of carbide alloy can got a mirror surface with Ra=0.025 μ m [similar to] 0.028 μ m. The relation between such physical natures as adhere strength, hardness, compact, conductivity of oxide film, and ingredient of grinding wheel, composition of grinding liquid as well as electrolytic parameters is studied. And the roles of oxide film in ELID grinding are also demonstrated. Various experiments were conducted to develop a new kind of grinding wheel for electrolytic in-process dressing (ELID) grinding. The results showed the best performance of ELID grinding when the weight proportion of powders of copper and iron was 10:82. The compactness of the oxide film conformed the performance of electrolytic passivation and activation of the grinding wheel. Key Issues of the Work: • The relation between characteristics of grinding wheel, composition of grinding liquid as

well as electrolytic parameters. • Development of new kind of wheel for electrolytic in-process dressing (ELID) grinding. Status: On-going Publications of this work: 1. J.L.Guan,et al.,2001,The application of ELID grinding technology in precision and super-

precision grinding of hard and brittle materials,Key Engineering Materials, Vol. 202-203, pp. 437-440

2. J.L.Guan, D.M.Guo, Z.J.Yuan., 2000, Research on the characteristics and roles of oxide film on grinding wheel of ELID mirror surface grinding,Chinese Journal of Mechanical Engineering, Vol. 36, No. 5, pp.89-92

3. J.L.Guan, D.M.Guo, Z.J.Yuan., 2000, Precision mirror surface grinding of carbide alloy, China Mechanical Engineering, Vol. 11,No. 3, pp. 288-289

4. J.L.Guan,et al.,2001,The application of ELID grinding technology on external precision mirror surface, Key Engineering Materials, Vol. 202-203, pp. 419-422

5. J.L.Guan,et al.,2001,Research on metal cement grinding wheel for ELID precision mirror surface grinding, Key Engineering Materials, Vol. 202-203, pp. 355-358

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C5 Measurement and Precision Grinding of Part with Complicated Surface Grinding machine design and control systems

Contact Information: Professor D.M.Guo, Professor Z.Y. Jia, Professor R.K. Kang Key Laboratory for Precision & Non-traditional Machining Technology of Ministry of Education School of Mechanical Engineering Dalian University of Technology, Dalian, 116024，P. R. China, Phone: +86-411-84706059 Email: [email protected] Abstract: The radome is a revolution shell part made of hard and brittle material and has 3-D complex curved surface. The electric thickness of radome after semi-finished can usually not meet the requirement of the design owing to the error of the geometric thickness and the non-uniformity of the dielectric constant of the material. Therefore, it is necessary to precisely grind the inner surface of the radome. A three-axis CNC precision measuring and grinding machine tool, which is controlled by a industrial personal computer (IPC) and a programmable multi-Axis controller (PMAC), was designed and developed. In order to avoid installation errors caused by separate loading operation and to ensure the grinding accuracy, the measuring and grinding process of the radome are accomplished in the same installing position on the machine tool in a manner of "once-loading and two-step-operation". First, the inner surface is precisely measured to set up a process datum and then, the finish grinding process is performed based on the datum and the required grinding allowance in the machine tool. Key Issues of the Work: • Design and development of CNC measuring and grinding machine • Precision grinding techniques for hard and brittle material Part with Complicated Surface Status: On-going Publications of this work: 1. Z.Y. Jia, T. Ji, D.M.Guo and G.H. Bian., 2004, A Precision Grinding Technique for Radome

Inner Surfaces, Key Engineering Materials, Vol. 257-258, pp. 177-182. 2. D.M. Guo, Z.Y. Jia, T. Ji, X.J. Sheng and L.H. Jiang.,2004, Study on the CNC Grinding

Machine Tool for Radome Inner Surface, Key Engineering Materials, Vol. 259-260, pp. 677~681.

3. Ji Tian, Guo Dongming and Kang Renke., 2004, Grinding Path Calculation for the CNC Grinding Machine for a Radome, China Mechanical Engineering, Vol. 15,No.10, pp. 859-861.

4. D. M. Guo, M. J. Liu, R. K. Kang, J. M. Liu., 2003,Determination of the grinding area and allowance in the radome grinding, Key Engineering Materials, Vol.259~260,pp. 174-179

5. T.Ji,D.M.Guo,Z.Y.Jia,R.K.Kang,A.F.Shi., 2004,Study on process parameters for radome inner surface precision grinding with electroplated diamond wheel, Diamond and Abrasives Engineering ,No. 5, pp. 28-32

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C7 Belt Grinding of Brittle Materials Contact Information: Professor Wang Chengyong (C.Y.Wang) Institute of manufacturing Technology School of Mechanical Engineering Guangdong University of Technology Guangzhou 510090 China Email: [email protected] http://imt.gdut.edu.cn Abstract: Hard-brittle materials (such as granite, vitreous ceramic) are difficult to machine because of their high hardness and brittleness. Belt grinding may be one of the machining methods to them due to its cold grinding performance, high removal rate, precision dimension and lower cost. In order to check the posibility using belt grinding for making brittle materials prescise plates the analysis of the mechano-chemical grinding mechanism with different types of surfactants was studied. Polarized-light microscopy, X-ray diffraction and X-ray photoelectron spectrum were adapted to observe the material surfaces. The adaptability of abrasive belts to the grinding of granite, marble and ceramic tile by a platen belt grinding machine was analyzed by means of a series of tests. The influences of elementary elements, such as materials of abrasives and workpiece, table moving styles, etc., on material removal rate and surface roughness have been discussed. A new way that counting the wear grits of belt through three-dimensional microscope was proposed to analyze belt abrasives wear. The computer simulation of surface appearance of belt grinding has been done to simulate grinding process. Key Issues of the Work: • Surface characteristics of brittle materials acted by surfactant • Adaptability of abrasive belts to the grinding of various materials Status: On-going, Supported by NSFC, China Publications of this work: 1. C.Y.Wang, Y.H. Sun, Z.Qin, Platen belt grinding of brittle materials. Key Engineering

Materials, 2004, 257-258:129-134. 2. C.Y.Wang, Z.Qin, X.Wei, Y.X.Wu, Process of granite belt grinding. Key Engineering

Materials. 2003, 238-239:111-116. 3. C.Y. Wang, X.Wei, Z.C Pan, and Y.X Song. Effects of surfactant in stone machining. Key

Engineering Materials. 2003,250:194-199. 4. Z.Qin ， C.Y.Wang ， F.L.Zhang ， X.Wei. Properties of Granite Grinding Surface. Key

Engineering Materials. 2001,202-203:285-288.

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C8 Frame Sawing of Stone Contact Information: Professor Wang Chengyong (C.Y.Wang) Institute of manufacturing Technology School of Mechanical Engineering Guangdong University of Technology Guangzhou 510090 China Email: [email protected] http://imt.gdut.edu.cn Abstract: Frame sawing with diamond blades is a kind of widely used machining technique in stone industry. The diamond segments are welded on the thin and long blade in a huge machine. The inhomogeneity stone block is split into slabs by means of the reciprocating movement and vertical down feed of diamond blades. In frame sawing the removal processes are carried out by many diamond grits on the surface of diamond segments. Frequently there are problems or uncertainties in practice when developed types of segments are used for the first time or the suitable diamond segments for stone have to be selected without any experience. The prerequisite for a systematic selection, development and optimization of diamond blade is the basic knowledge on the effects of the parameters, which have an effect on the wear reaction as well as the load on the diamond blades and segments. The frame sawing phenomena such as sawing force, sawing diamond segments wear and the optimization of the working parameters have been studied by theoretical analysis, industrial measurements, simulating tests in lab and computer simulation. To better understand these phenomena are very important for both diamond blades manufacturer and stone machining factory for meeting the need of making good quality product with high productivity and low cost. Key Issues of the Work: • Kinematic basis of frame sawing process • On-line measuring of cutting force and segment wear • Test methods to simulate the frame sawing process in laboratory Status: On-going, Supported by NSFC, China; industry and Technical University Hamburg-Harburg, Germany Publications of this work: 1. C.Y.Wang, R.Clausen. Computer simulation of stone frame sawing process using diamond

blades. International Journal of Machine Tools and Manufacture. 2003, 43(5):559-572 2. C.Y.Wang, R.Clausen. Frame Sawing of Stone - Theory and Technology. Key Engineering

Materials. 2003, 250:170-181 3. C.Y.Wang, R.Clausen. Marble Cutting with Single point cutting tool and diamond segment.

International Journal of Machine Tools and Manufacture., 2002, 42(9):1045-1054,() 4. C.Y.Wang，R.Clausen. Stone Sawing Forces by Single Diamond Segment. Advances in

Grinding and Abrasive Processes. Key Engineering Materials. 2001, (202-203):61-66.

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C9 Grinding of Ceramic Tile Contact Information: Professor Wang Chengyong (C.Y.Wang) Institute of manufacturing Technology School of Mechanical Engineering Guangdong University of Technology Guangzhou 510090 China Email: [email protected] http://imt.gdut.edu.cn Abstract: Porcelain tiles, which are also called vitreous tiles, are widely used in the decoration of floors and walls for hotel, office and family buildings. Most vitreous tiles will be ground in the grinding and polishing machines as final products including surface planarization, edge grinding, sawing, surface grinding and polishing. Because the special properties of vitreous ceramic tiles and machining conditions, such as high hardness, wear resistance and brittleness (very thin piece, usually 5-8 mm in thickness), unfixed and with large surface deflection, the grinding and polishing processes of vitreous ceramic tiles have many problems.

In this project, the material removal process will be studied in detail for getting more information of the generation of glossiness surface and thin surface micro-crack layer using diamond tool or SiC and Al2O3 grinding wheels. The factors influenced the wear of grinding wheel, productivity and surface quality, such as performance of diamond tool and SiC and Al2O3 abrasive grinding wheel; grinding pressure and the characters of ceramic tiles etc. are analyzed based on a large amount of tests on a designed machine. The optimized parameters and rules will be proposed to the manufacturers of grinding wheels and ceramic tiles. Key Issues of the Work: • Formation of glossiness surface using various grinding wheels • Processing optimization in different grinding steps • On-line measuring the wear of grinding wheels rapidly Status: On-going , Supported by R & D project of Guangdong Province and industry Publications of this work: 1. C.Y.Wang T.C.Kuang Z.Qin X.Wei. How abrasive machining affects surface characteristics

of vitreous ceramic tile. American Ceramic Society Bulletin. 2003,10:9201-9208 2. C.Y.Wang, X.Wei, H.Yuan. Polishing of ceramic tiles. Materials and Manufacturing Process.

2002,17(3), 401–413

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C10 Sawing of Concrete with Diamond Sawing Blade Contact Information: Professor Wang Chengyong (C.Y.Wang) Institute of manufacturing Technology School of Mechanical Engineering Guangdong University of Technology Guangzhou 510090 China Email: [email protected] http://imt.gdut.edu.cn Abstract: Because of fast cutting rate, high accuracy, long tool life and low costs, diamond saw blades are used to make expansion and contraction grooves on the surface of concrete road, to saw joints and anti-skid grooves of highways and airport runways, and to cut off floors and walls. High cutting temperature, high noise and serious powders of chips are caused during dry cutting process of concrete. The concrete chips cause not only the lower blade life and sawing efficiency when they adhere to saw blade surface, but also the pollution to the environment. There is a demand for understanding processing mechanism, optimizing cutting conditions and saw blade structure to increase saw blade life and decrease cutting costs in concrete sawing. In order to find out the characters of concrete sawing and improve the application and manufacturing of diamond saw blade for civil engineering, the sawing mechanism, forces, noise, vibration of different concrete especially reinforced concrete in dry cutting process were investigated. The factors affecting cutting process of concrete were analyzed, which included the strength of concrete, the composition of reinforced concrete, the performance of saw blades and the cutting parameters. The deformation and fatigue of saw blade with different structures are analyzed for obtaining the minimum and uniform distribution of temperature and stress by means of FEM method and kinetic analysis method. Key Issues of the Work: • Sawing process of concrete with diamond saw blades • Theoretical models of sawing process • Rapidly distinguish of blade wear Status: On-going, Supported by NSFC, China and industry Publications of this work: 1. C.Y. Wang, Y.N. Hu, H.N. Ding. Cutting Forces in Sawing Process of Reinforced

Concrete . Materials Science Forum; 2004, 471-472: p292-297. 2. Y.N Hu, C.Y.Wang, H.N. Ding. The Mechanics Performance Study of Diamond Saw Blades

With Special Structure. Key Engineering Materials. 2004, 259-260:p41-45. 3. Y.N Hu, C.Y.Wang, X.Wei and Z.G.Li. Thermodynamic Analysis of Diamond Saw Blades

for Dry Cutting. Key Engineering Materials. 2003, 250: p233-238.

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4. X. Wei, H.W. Du, C.Y. Wang, Y.L. Fang. Investigation of Cutting Forces in Concrete Sawing Process. Key Engineering Materials. 2003, 250:181-186.

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C11 Aspherical Surface Grinding Contact Information: Professor Feihu Zhang Dept. of Mechanical Manufacturing and Automation School of Mechanical and Electrical Engineering Harbin Institute of Technology Harbin, China, 150001 Email: [email protected] Abstract: A parallel grinding system has been built based on an ultra-precision machine, and a CNC system controlled by PMAC (programmable multi-axis controller) been developed. By adopting arc envelope grinding method (AEGM), the wear of wheel is diminished and the tool path calculation simplified. The system has been used to grind concave aspherical surface, the roughness and profile accuracy of aspheric surface are improved. Key Issues of the Work: • A parallel grinding system for grinding concave aspherical surface • Arc envelope grinding method Status: On-going Publications of this work: 1. L. J. Li, F. H. Zhang, S. Dong, 2004, Research on Parallel Grinding Method of Aspheric

Optics, Proc. of ICoPE 2003/04 Conference, Singapore, pp.3 -8 2. Mingjun Chen, Feihu Zhang, Qingliang Zhao, Shen Dong, 2001, Study of Ultra-precision

Grinding Machining of Optical Aspheric Surface in Ductile Mode, SPIE, vol.4451, pp.191-199

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C12 ELID Grinding Contact Information: Professor Feihu Zhang Dept. of Mechanical Manufacturing and Automation School of Mechanical and Electrical Engineering Harbin Institute of Technology Harbin, China, 150001 Email: [email protected] Abstract: ELID (Electrolytic In-process Dressing) technique has been used to the ultra-precision grinding of ceramic glass, nano ceramics and other hard and brittle materials. Analyzed by using AFM, the grinding surfaces are in ductile remove mode. ELID technique has also been used to the high efficiency deep grinding of ceramics and ferrite. The grinding force of ELID grinding is apparently smaller than that of grinding with resin bond diamond wheel. Key Issues of the Work: • Ultra-precision ELID grinding of hard and brittle materials • High efficiency deep ELID grinding Status: On-going Publications of this work: 1. F. H. Zhang, Z. J. Qiu, D. R. Luan, 2001,Ultra-precision Grinding of Ceramic Glass with

ELID Technique, Key Engineering Materials, Volumes 202-203(2001), pp.103-108 2. Feihu Zhang, Guiwen Kang, Zhongjun Qiu, 2002, High Efficiency ELID Grinding of

Alumina Ceramics, Key Engineering Materials, V0l.238-239, pp.71-76, 3. F. H. Zhang, Y. Z. Liu, J. C. Gui and H. J. Wang，2003, A Study of the ELID Grinding for

Nano Ceramics, Key Engineering Materials, Vols. 257-258, pp119-122

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C13 Precision Grinding of Nanostructured Ceramics Coatings Contact Information: Professor Zhaohui Deng College of Mechanical & Automative Engineering Hunan University, Changsha, Hunan 410082, P.R.China Email: [email protected] http:www.hunu.edu.cn Abstract: Experimental studies of precision grinding of nano-structured ceramic coating have shown that : • The grinding mark is the most significant characteristic on the ground n-WC/12Co coating

under all grinding conditions, and the most significant characteristic on the ground n-Al2O3/13TiO2 coatings is brittle fracture.

• Two major crack patterns are identified in nanostructured ceramics grinding: medial radial cracks, lateral cracks.

• Based on the critical load for lateral cracking, the material-removal mechanism can be quantitatively analyzed.

• Critical grinding condition models predicting grinding induced lateral cracks in nanostructured ceramic coatings are proposed, which are also verified by the experiments.

• The dominant material removal mechanism of precision grinding of n-WC/12Co coatings is primarialy inelastic deformation including plastic deformation and certain pulverization and less material brittle fracture.

• The dominant material removal mechanism of precision grinding of n- Al2O3/13TiO2 coatings is brittle fracture including material brittle chippping and crushing in almost grinding conditions, simultaneously the material pulverization and mirco plastic deformation are also existed.

This study provides important insights into selecting appropriate grinding parameters for successful grinding of nano-structured materials. Key Issues of the Work: • Observing the morphology of surface/subsurface of nanostructured WC/12Co coatings and

nanostructured Al2O3/13TiO2 ground at different grinding parameters by using SEM. • Mearsuring the grinding forces and grinding force ratio and specific grinding energy

generated during grinding of nanostructured WC/12Co coatings and nanostructured Al2O3/13TiO2 ground at different grinding parameters.

• Measuring surface roughness • Establishing the mathematical models predicting grinding induced cracks. Status: On-going Publications of this work: 1. Deng Z H, Jin Q Y, Zhang Bi. Critical Grinding Condition Models for Predicting Grinding Cracks in

Nanostructured Ceramic Coatings. Key Engineering Material,2004,259－260：273－277

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2. Deng Zhaohui, Liu Jian, Cao Defang et al. Material Removal Mechanism and Advanced Grinding Techniques for Nanostructured Ceramic Coatings. Diamond & Abrasives Engineering, 2003,12(Serial136):5-11

3. Deng Zhaohui, Zhang Bi, Sun Zongyu. An Experimental Study on Precision Grinding of Nanostructured Ceramic Coatings. Journal of Hunan University,2003,30(2):35-40

4. Deng Zhaohui, Zhang Bi, Sun Zongyu. Study on the Material Removal Mechanism of Grinding of Nanostructured Al2O3/13TiO2 Coatings.China Mechanical Engineering, 2005,At press

5. Deng Zhaohui, Zhang Bi, Sun Zongyu. Morphology of the Ground Surface/subsurface of Precision Grinding of Nanostructured Ceramic Coatings. Journal of Chinese Ceramic Society, 2005,33(3),At press

6. Xianbing Liu, Bi Zhang, Zhaohui Deng. Grinding of nanostructured Ceramic coatings: surface observations and material removal mechanisms.International Journal of Machine Tools & Manufacture,42(15),(2002):1665-1676

7. Bi Zhang, Xianbing Liu, Zhaohui Deng, et al .Grindiability comparison between conventional and nonstructured material coatings. Proceedings of the 5th International Conferenceon on Frontiers of Design and Manucfacturing (ICFDM’2002):1-5

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C14 Surface Quality Studies with Respect to Grinding Burn of new Typical Nickel-Based Superalloy

Contact Information: Prof. Chen Ming School of Mechanical Engineering Shanghai Jiao Tong University 200030，Shanghai P.R.China Email: [email protected] Abstract: Excessive grinding temperature leads to thermal damage that greatly deteriorates the surface quality and has an adverse effect on in-service strength and fatigue properties. Grinding burn is the common type of thermal damage that has been becoming the main conscious issue in grinding difficult-to-cut materials with regard to high efficiency and good integrity as well as high accuracy. Directionally solidified nickel-based superalloy DZ4 is a kind of very important structural material developed nowadays domestically, but the very poor machinability hinders its broad utilization in aircraft. This paper unveiled its grinding burn mechanism by experimentally analyses of grinding process characteristics such as grinding forces and grinding temperature, and also by metallurgical examinations for the surface integrity. When grinding temperature reaches 1100°C, grinding burn occurs and the mechanical strength as well as heat resistance of the DZ4 alloy deteriorates obviously. The residual tensile stress of burned surface layer is almost over 20 times as much as that of the normal state. Seldom oxidation occurs on the burned surface and there is no evident change in burn color from slight burn to severe burn, which is much different from that of carbon steel grinding. With the onset of grinding burn, the metallurgical phase of surface layer changes. The main strengthening γ ′ phases are soluted into γ base, the amount of fine strengthening particles γ ′ decreases, which causes the deterioration of strength. The large and irregularly distributed γ ′ phases in surface layer severely affect the coincidence of performance of DZ4. The surface hardness of DZ4 alloy weakens by 25% and the depth of affected layer exceeds 0.5mm. The grinding force ratio Fn/Ft changes remarkably as soon as grinding burn takes place and can be used as the characteristic parameter for the real time grinding burn monitoring. This paper will be beneficial to the catastrophic failure inspections and to the development of advanced grinding technologies related to avoidance of grinding burn. Key Issues of the Work: • Grinding burn mechanism discovery is very important to the technology optimization and

process control • The special superalloy is widely used in aeronautical engineer making and it has very poor

machinability. • Grinding temperature detection and metallurgical inspection as well as grinding forces

monitoring are keys to find burn mechanism. Status: completed

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Publications of this work: 1. Chen Ming, Li Xiaotian. Studies on Grinding Characteristics of Directionally Solidified

Nickel-based Superalloy. Journal of Materials Processing Technology. Vol.116 (2-3), 2001,10: 165-169

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C15 Ultraprecision Grinding of Tungsten Carbides for Optical Mirrors Contact Information: Professor Ling Yin School of Mechanical Engineering Tianjin University Tianjin 300072, China Tel & Fax: (86)(22) 2740 1009 Email: [email protected] Abstract: This project focused on the ultra-precision grinding of tungsten carbides for spherical and planar mirrors with nanometer surface roughness and submicron form accuracy. The influence of microstructure on the ultra-precision grinding response of a series of cemented carbides for spherical mirrors was characterized by means of optical and laser interferometry, atomic force microscopy, scanning electron microscopy and X-ray diffraction. Surface roughness, form accuracy, grinding-induced residual stress and material removal behaviors were studied as a function of tungsten carbide (WQ grain size. In connection with the removal mechanisms in ultra-precision grinding, micro-indentations performed on each material showed similar deformation patterns, all in the plastic regime. The microstructure of WC-Co materials was found to have little influence on the nanometer surface roughness and submicron form accuracy. However, the X-ray stress measurements indicated that the microstructure of carbide materials had a significant influence on the grinding-induced residual stresses; i.e. an increase in grinding-induced residual compressive stress with an decrease in WC grain size. No grinding-induced cracks were observed in the ground cemented carbide surfaces. The material removal in ultra-precision grinding was considered to occur within the ductile regime. The formation of microgrooves and plastic flow regions via slip bands of WC grains along the cobalt binder without visible resultant micro-fracturing of WC grains were the dominant removal mechanisms. The results show that ultra-precision grinding can be applied to the direct fabrication of spherical and planar mirrors made of tungsten carbides without addition lapping and polishing processes. Key Issues of the Work: • Ultraprecision grinding and optical quality measurements; • Microstructure response to ultraprecision grinding. Status: Completed 2002 Publications of this work: 1. L. Yin, J.P.Pickering, K. Ramesh, H. Huang, A. Spowage, E. Y. J. Vancoille. Planar

nanogrinding of a fine grained WC-Co composite for optical surface finish. International Journal of Advanced Manufacturing Technology, in press.

2. L. Yin, E. Y.J. Vancoille, K. Ramesh, H. Huang, J. P. Pickering, A. C. Spowage. Ultraprecision grinding of tungsten carbide for spherical mirrors,. Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture, 218(4) (2004) 419-429.

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3. L. Yin, A. Spowage, K. Ramesh, H. Huang, J.P. Pickering, E. Y. J. Vancoille. Influence of microstructure on ultraprecision grinding of cemented carbides. International Journal of Machine Tools & Manufacture, 44(5)(2004)533-543.

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C16 Dental Finishing Grinding Research Contact Information: Professor Ling Yin School of Mechanical Engineering Tianjin University Tianjin 300072, China Tel & Fax: (86)(22) 2740 1009 Email: [email protected] Abstract: This project focused on bioceramic response to abrasive finishing in dental restorations. Key Issues of the Work: • Abrasive machining; • Machining-inducted damage. Status: On-Going Publications of this work: 1. L. Yin, L. K. Ives, S. Jahanmir, E. D. Rekow, E. Romberg. Abrasive machining of glass-

infiltrated alumina with diamond burrs. Machining Science & Technology - An International Journal, 5 (1) (2001) 43-61.

2. X. Dong, L. Yin, S. Jahanmir, L. K. Ives, E. D. Rekow. Abrasive machining of glass-ceramics with a dental handpiece. Machining Science & Technology, An International Journal, 4 (2) (2000) 209-233.

3. L. Yin, L. K. Ives, S. Jahanmir. Effects of fluids on the simulated clinical dental machining of a glass ceramic. Journal of the American Ceramic Society, 87 (1) (2004) 173-175.

4. L. Yin, S. Jahanmir, L. K. Ives. Abrasive machining of porcelain and zirconia with a dental handpiece. Wear, 255 (2003) 975-989.

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C17 High Workspeed Deep Grinding of Ceramics Contact Information: Professor Ling Yin School of Mechanical Engineering Tianjin University Tianjin 300072, China Tel & Fax: (86)(22) 2740 1009 Email: [email protected] Abstract: Recent progress in the miniaturization of electronic items introduces manufacturing challenges for achieving both better surface integrity and high throughput. Controlled thermal interaction processes physically vaporize the material for producing the miniature components but the poor surface and sub-surface characteristics introduce a niche for thermo-mechanical processes, particularly microgrinding. Prior microgrinding attempts have focussed on axi-symmetrical components of hard-brittle materials. For non-axisymmetrical, high-aspect ratio miniature components, edge chipping was encountered. This paper reports a new grinding method that uses "high table reversal speeds" for reducing the "grit cut load" and hence facilitates the microgrinding process. An arrangement that functions on the principles of four bar linkage with a sliding and rotating pair was devised. This arrangement was designed to reciprocate between 300-1000 strokes/min for a stroke length of 10-70 mm. As a result the table feed rate range was increased from the conventional 300-20 000 mm/min to 5000-55 000 mm/min. Process characterization of the new grinding method was observed for hard-brittle materials. A physical model was developed which links the process parameters with appropriate boundary conditions and the model was verified experimentally. The experimental model was used to explain the mechanism of grinding while employing high table reversal speeds. Process characterization includes grinding force, grinding-ratio, grinding wheel topography, surface finish and SEM study. Also, the process was applied to produce mold-insert which in turn was used for molding the micro-mechanical cantilever sensor parts. Deep slots of size: 1.2 x 0.1 x 1.5 mm with an aspect ratio of 15 was successfully produced with this method. The new grinding device and method promote microgrinding through integration to an existing grinder and therefore reduces the additional cost on the capital resources Key Issues of the Work: • Ceramic response to high speed grinding Status: Completed 2001 Publications of this work: 1. L. YIN, H. Huang, K. Ramesh, T. Huang. High speed versus conventional grinding

in high removal rate machining of alumina & alumina-titania. International Journal of Machine Tools & Manufacture, in press.

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2. H. Huang, L. YIN, L. Zhou. High speed grinding of silicon nitride with resin bond diamond wheels. Journal of Material Processing Technology, 141 (3) (2003) 329-336.

3. L. YIN, H. Huang. Ceramic response to high speed grinding. Machining Science & Technology - An International Journal, 8(1) (2004) 21-37.

4. K. Ramesh, H. Huang, L. YIN, J. Zhao. Microgrinding of deep micro grooves with high table reversal speed. International Journal of Machine Tools & Manufacture, 44(1)(2004) 39-49.

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C18 High-Quality & Low-Damage Grinding of Polycrystalline Silicon Carbide Spherical Surfaces

Contact Information: Professor Ling Yin School of Mechanical Engineering Tianjin University Tianjin 300072, China Tel & Fax: (86)(22) 2740 1009 Email: [email protected] Abstract: This project focused on the high-quality and low-damage grinding of polycrystalline silicon carbide spherical surfaces to achieve nanometre surface roughness and submicron form accuracy. The work provides technical insights into precision engineering for rapid manufacturing of ceramic components without the need or with less need for subsequent lapping and polishing. Key Issues of the Work: • Basic understanding low-damage grinding mechanisms of silicon carbide; • X-ray diffraction tests for the ground SiC surfaces. Status: Completed 2002 Publications of this work: 1. L. YinN, E. Y. J. Vancoille, L. C. Lee, Y. C. Liu, H. Huang, K. Ramesh. High-precision low-

damage grinding of a polycrystalline silicon carbide. Key Engineering Materials, 238/239 (2003) 59-64.

2. L. Yin, E. Y. J. Vancoille, L. C. Lee, H. Huang, K. Ramesh, X. D. Liu. High-quality grinding of polycrystalline silicon carbide spherical surfaces. Wear, 256 (1/2) (2004) 197-207.

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C19 Optic Fibre Connector End Polishing & Grinding Contact Information: Professor Ling Yin School of Mechanical Engineering Tianjin University Tianjin 300072, China Tel & Fax: (86)(22) 2740 1009 Email: [email protected] Abstract: This project focused on the high efficient polishing/grinding of optic fiber ends to obtain high geometrical and optical qualities. Key Issues of the Work: • Polishing/grinding of optic fibre connector ends; • Geometrical quality and optical quality measurement for connectors. Status: Completed 2003 Publications of this work: 1. L. YIN, H. Huang. Grindability of glass-inlaid zirconia for fibre Optic connectors.

Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture, in press.

2. L. YIN, H. Huang, W. K. Chen, Z. Xiong, Y.C. Liu, P.L. Teo. Polishing of fiberoptic connectors. International Journal of Machine Tools & Manufacture, 44(6) (2004)659-668.

3. W. K. Chen, H. Huang, L. YIN. Loose abrasive truing and dressing of resin bond diamond cup wheels for grinding fibre optic connectors. Journal of Materials Processing Technology, 159(2)(2005)229-239.

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C20 Surface Characterization of 6H-SiC (0001) Substrates in Indentation and Abrasive Machining

Contact Information: Professor Ling Yin School of Mechanical Engineering Tianjin University Tianjin 300072, China Tel & Fax: (86)(22) 2740 1009 Email: [email protected] Abstract: This project focused on the surface integrity associated with material removal and surface generation of 6H-SiC (0001) in indentation and abrasive machining. Surface characterization of 6H-SiC (0001) substrates in indentation and abrasive machining was carried out to investigate microfracture, residual damage, and surface roughness associated with material removal and surface generation. Brittle versus plastic deformation was studied using Vickers indention and nano-indentation. To characterize the abrasive machining response, the 6H-SiC (0001) substrates were ground using diamond wheels with grit sizes of 25, 15 and 7 pm, and then polished with diamond suspensions of 3 and 0.05 (im. It is found that in indentation, there was a scale effect for brittle versus plastic deformation in 6H-SiC substrates. Also, in grinding, the scales of fracture and surface roughness of the substrates decreased with a decrease in diamond grit size. However, in polishing, a reduction in grit size of diamond suspensions gave no significant improvement in surface roughness. Furthermore, the results showed that fracture-free 6H-SiC (0001) surfaces were generated in polishing with the existence of the residual crystal defects, which were associated with the origin of defects in single crystal growth Key Issues of the Work: • Vickers and nana- indentation; • Brittle versus plastic deformation for 6H-SiC (0001) substrates. Status: Completed 2002 Publications of this work: 1. L. YIN, E. Y. J. Vancoille, K. Ramesh, H. Huang. Surface characterization of 6H-SiC (0001)

substrates in indentation and abrasive machining. International Journal of Machine Tools & Manufacture, 44 (6) (2004) 607-615.

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C21 Condition Monitoring and Field Dynamic Balance System in Grinding Contact Information: Professor Yinbiao Guo Research Associate: Yi Zhang Department of Mechanical and Electrical Engineering Xiamen University China, 361005 Email: [email protected] [email protected]: http://mee.xmu.edu.cn Abstract: Experimental studies have shown that the vibration of grinding wheel and workpiece caused by the factors such as mass heterogeneity and eccentric installation, directly influence workpiece surface quality. It often pays attention to the dynamic balance of wheel or workpiece, but ignores the integral harmony between wheel and workpiece. From these tests a balanced system has been developed for condition monitoring and field dynamic balance. Key Issues of the Work: • Executing dynamic balance for workpiece and wheel • Condition monitoring during grinding Status: On-going Publications of this work: 1. Yinbiao Guo, 2003, Study on Condition Monitoring and Balance Technique of Ultra-

Precision Grinding System, Mechanical & Electrical Technology(In Chinese), pp. 128-131.

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C22 Ultra-precision Grinding and Polishing of Micro Aspheric Surface Contact Information: Professor Yinbiao Guo Research Associate: Yi Zhang Department of Mechanical and Electrical Engineering Xiamen University China, 361005 Email: [email protected] [email protected] http: http://mee.xmu.edu.cn Abstract: Developing a prototype system of grinding and polishing of micro aspheric surface, emphasis is put to analyzing the nano-topography characterization, and dealing with micro grinding method and magnetorheological fluid-assisted polishing method for small three-dimensional parts such as micro-aspheric lens, die and mirror. Micro-aspheric generator system is developed, which is capable of micro-grinding and micro-polishing on the same machine. The system will demonstrate excellent polishing performance of small area after grinding process.

Key Issues of the Work: • Developing ultra-fine micro abrasive wheel • Utilizing locus optimization and error compensation to develop the process accuracy • Studying the effect of MRF fluids on the polishing accuracy of aspheric surface • Developing a figure measurement system Status: On-going Publications of this work: 1. Yinbiao Guo, Research on Parallel Grinding Method of Non-axisymmetric Aspheric Lens,

Chinese Journal of Mechanical Engineering, Vol.17,No1, 2004:149-151 2. Yi Zhang, Yinbiao Guo, Research on Effect Conditions of Micro Vibration in Ultra-precision

Grinding of Aspheric Surface Key Engineering Materials Vols.259-260 (2004) pp.430-434

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C23 Form-grinding Hard Material by Super-hard Grinding Wheel with High Precision and Efficiency

Contact Information: Professor Zhongming Cui College of Mechanical Engineering, Henan University of Technology, No.195 of Zhongyuan Road 450007 Zhengzhou city P.R.CHINA Phone: +86-371-7651882 E-mail: [email protected] Abstract: Currently, application of hard PCD and PCBN materials is universal in modern industry. Form-grinding hard material by super-hard grinding wheel in high precision and efficiency is the most effective method for machining hard material with high precision, complicated profiler in high efficiency. Super hard grinding wheel means diamond and CBN grinding wheel. Dressing profiler of super-hard Grinding wheel is one of key techniques in grinding process. It is required that dressing process of profiler of super hard grinding wheel shall be not only in high precision degree but also in high efficiency. The research concludes after a series research work, that forming diamond rotary dresser can dress the profile of super hard grinding wheel not only for high precision but also for high efficiency. Dressing grinding wheel by forming diamond rotary dresser can be divided into three actions, namely pressing, friction and cutting, and they fulfilled dressing together, dressing can take effective advantage of comprehensive actions of pressing and cutting. Form-grinding by diamond wheel can reach 5micro in profiler and 3micro in teeth, which can meet requirements

Key Issues of the Work. • Manufacturing technology of forming diamond rotary dresser • Mechanism of dressing • Form-dressing parameters Status：completed . Publications of this work: 1. W.H. Yan, Z.M. Cui Studies on Truing and Sharpening of CBN Wheel, Abrasive &Grinding

1994.1, p.2 2. Z.M. Cui: Recent Development of Technique of Diamond Dressing Tools, Treatises

Collection of 98’Zhengzhou International Super-hard Material and Related Products Conference, p.25

3. Z.M. Cui: New Development of Grinding Wheel Dressing Technique in Grinding Process, Treatises Collection Of The Eighth Academic Congress Of Chinese Production Engineering Society 1999.9, p.347

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C24 Forces, Energy and Temperature during the Sawing Process with Diamond Tools Contact Information: Professor Xipeng Xu (X.P. Xu) Province Key Research Lab for Stone Machining Huaqiao University, Quanzhou Fujian 362021, P.R. China Tel: ++86-595-22693598 Fax: ++86-595-22693999 Email: [email protected]://info.hqu.edu.cn/stone/english/ Abstract: Diamond tools are extensively used in the processing of brittle materials, especially in the sawing of natural stone. During the sawing, diamond abrasive grits interact with stone and do the cutting. The cutting behavior depends on the processing parameters, the working state of the tools’ surface, the property of the stone and etc. A fundamental understanding of what happens during sawing is needed in order to provide a technological basis for enhancing the process efficiency and the performance of the diamond tools. Measurements are made of the forces, power and temperature over a wide range of sawing conditions to make further understanding of the sawing process of stone. Key Issue of the Work: • Measuring and calculating of the forces and power during the sawing process • Determining the coefficient of the energy partition in the sawing arc Status: On-going Publications of this work: 1. Xipeng Xu, Yuan Li, Yiqing Yu, 2003, Force Ratio in Circular Sawing of Granites with

Diamond Segmented Blade, Journal of Materials Processing Technology, Vol. 139, No.1-3, pp. 281-285.

2. Xipeng Xu, Hui Huang, Weimin Zeng, Stephen Malkin, 2002, Thermal Aspects for Grinding of Granite，Transactions of NAMRI/SME, Vol.30.

3. X.P. Xu, Y. Li, W.M. Zeng, L.B. Li, 2002, Quantitative Analysis of the Loads Acting on the Abrasive Grits in the Diamond Sawing of Granites, Journal of Materials Processing Technology, Vol.129, No.1-3, pp. 50-55

4. Xipeng Xu, Malkin S., 2001, Comparison of Methods to Measure Grinding Temperatures, Transactions of the ASME: Journal of Manufacturing Science and Engineering,Vol.123, No.3, pp. 191-195

5. Xipeng Xu, 2001, Experimental Study on Temperatures and Energy Partition at the Diamond-granite Interface in Grinding, Tribology Interntional, Vol.34, pp. 419-126

6. Xipeng Xu, Yuan Li, Malkin S, 2001, Forces and Energy in Circular Sawing and Grinding of Granite, Trans. of ASME: J. of Manuf. Science and Eng., Vol.123, No.1, pp. 13-22

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C25 Generation Mechanisms of Machined Surface Layer in Polishing of Granite Contact Information: Professor Xipeng Xu (X.P. Xu) Province Key Research Lab for Stone Machining Huaqiao University, Quanzhou Fujian 362021, P.R. China Tel: ++86-595-22693598 Fax: ++86-595-22693999 Email: [email protected]://info.hqu.edu.cn/stone/english/ Abstract: In order to understand the generation mechanisms of machined surface layer in fixed abrasive polishing of granite, the topographic features of the polished granite surfaces were quantitatively evaluated in terms of surface roughness and gloss readings in addition to SEM and AFM observations. Temperature responses at the workpiece-tool contact zone were in-process monitored by using a pair of grindable thermocouple. Experimental results have shown that the reduction in surface roughness, and hence the increase in surface glossiness, are mainly dependent on the mechanical interactions between the diamond grits and granites, rather than thermally induced chemical reactions. Key Issues of the Work: • Measurement of the temperature rises at workpiece-tool contact zone in polishing of granite • Evaluation of the topographic features of polished granite surfaces Status: On-going Publication of this work: 1. H. Huang and X. P. Xu, 2004, Interfacial interactions between diamond disk and granite during

vertical spindle grinding, Wear, Vol.256, No. 6, pp. 623-629 2. X.P. Xu, H. Huang, Y. Gao, 2003, Processes for the generation of glossiness on ground granites and

ceramics, Key Engineering Materials, Vols.238-239, pp. 99-104 3. H. Huang, Y. Li, J.Y. Shen, X.P.

http://www.engineeringvillage2.com.cn/controller/servlet/Controller?CID=quickSearchCitationFormat&searchWord1=%7bZhu%2C+H.M.%7d&section1=AU&database=1&startYear=1969&endYear=2005&yearselect=yearrangeXu, 2002, Micro-structure detection of a glossy granite surface machined by the grinding process, Journal of Materials Processing Technology, Vol. 129, No.1-3, pp.403-407.

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C26 Manufacturing of Metal-bonded Diamond Abrasive Tools for Stone Processing and the Evaluation of their Grinding Performance

Contact Information: Professor Xipeng Xu (X.P. Xu) Province Key Research Lab for Stone Machining Huaqiao University Quanzhou, Fujian 362021 P.R. China Tel: ++86-595-22693598 Fax: ++86-595-22693999 Email: [email protected]://info.hqu.edu.cn/stone/english/ Abstract: Metal-bonded diamond abrasive tools for processing natural stone materials consist of randomly dispersed diamond crystals embedded in a metal bond matrix. The main role of the matrix is to ensure maximum cutting productivity of the diamond grits by holding them firmly until they are worn out. The matrix and the diamond wear rates should be appropriately matched in order to attain an optimum balance between its in-service life and free-cutting ability. A fundamental understanding of what mainly affects the retention ability of the matrix and what affects the wear of the diamond tools is required in order to provide a technological basis for optimizing the design of diamond tools and consequently improving their grinding performance. Key Issue of the Work: • Factors influencing the performance of metal-bonded diamond tools: matrix, modification of

diamond grits, application of active additives, manufacturing process control • Analysis of the diamond-matrix interface • Evaluation of the surface working state of the diamond tools Status: On-going Publications of this work: 1. X.P. Xu, Y.Q. Yu, 2005, Sawing Performance of Diamond with Alloy Coatings, Surface and

Coatings Technology, in press. 2. X.P. Xu, H. Huang, 2004, High-Efficiency Cutting of Granite Blocks with Multi-Blade

Diamond Saws，Key Engineering Materials, Vols.257-258, pp. 297-302. 3. Q.L. Dai, X.P. Xu, 2002, Effects of rare earth and sintering temperature on the transverse

rupture strength of Fe-based diamond composites ， Journal of Materials Processing Technology, Vol.129 (1-3), pp. 427-430.

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C27 Precision Grinding of Advanced Ceramics Contact Information: Professor Xipeng Xu (X.P. Xu) Province Key Research Lab for Stone Machining Huaqiao University, Quanzhou Fujian 362021, P.R. China Tel: ++86-595-22693598 Fax: ++86-595-22693999 Email: [email protected]://info.hqu.edu.cn/stone/english/ Abstract: Extensive studies on high efficiency and precision machining of ceramic materials have shown that the grinding temperatures of advanced ceramics are very significant on the quality of the grinding process. It is found that the temperature rises in the workpiece and energy partition during the grinding process are directly related to the machining parameters and the mechanism of material removal. It is also found that the high quality surface of advanced ceramics can be obtained in ductile regime grinding.

Key Issues of the Work: • Measurement of temperatures in grinding of advanced ceramics • Grinding of advanced ceramics in ductile regime Status: On-going Publications of this work: 1. Shen, J.Y., Xu, X.P.; Lin, B.; Xu, Y.S., 2001, Lap-grinding of Al2O3 ceramics assisted by

water-jet dressing metal bond diamond wheel, Key Engineering Materials, Vols.202-203, pp. 171-176.

2. Shen, J.Y., Zeng, W.M.; Huang, H.; Xu, X.P., 2002, Thermal aspects in the face grinding of ceramics Source: Journal of Materials Processing Technology, Vol.129, No.1-3, pp. 212-216

3. Shen, J.Y., Li, Y.; Xu, X.P.; Gao, Y., 2003, Force and energy characteristics in grinding of ceramics, Key Engineering Materials, Vols. 238-239, pp. 105-110.

4. Shen, J.Y., Luo,C.B., Zeng, W.M., Xu, X.P., Gao, Y.S., 2002, Ceramics grinding under the condition of constant pressure, Journal of Materials Processing Technology, Vol. 129, pp.176-181.

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C28 CNC Twist Drill Grinding Modeling Contact Information: Dr. Zhixiong Zhou College of mechanical and automotive engineering Hunan University Changsha, 410082 P.R.China Email: [email protected] Abstract: This study involved the development of multi-facet twist drills and new micro-drill grinding processes. The project involved the development of a mathematical model for both of the grinding process, followed by the design of CNC grinding machines. The models was verified by grinding tests on the new machines. The multi-facet twist-drill project produced drills that are highly effective for production, giving 4-6 times the life of ordinary drills. Key Issues of this Work: Status: Completed Publications of this Work: 1. Only in Chinese

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C29 Determination of the Contact Length in Grinding Contact Information: Dr. Zhixiong Zhou College of mechanical and automotive engineering Hunan University Changsha, 410082 P.R.China Email: [email protected] Abstract: The contact state of the grinding wheel and workpiece can be partly described by the contact length. In this research, it was found the contact length between grinding wheel and workpiece cannot be described by that between one grain and workpiece, but should be measured over the full grinding contact area. This is because during grinding there a lots of main grain participating in the process at different radial distance from the axis of rotation. Therefore, the contact length produced by some grains may be longer, and some may be shorter. On the whole grinding area, maximum contact length, minimum contact length, and arbitrary contact length exist. The maximum contact length should be considered for the contact state between wheel and workpiece. The results can be found in the reference listed below. Key Issues of this Work: Status: Completed Publications of this Work: 1. Z. Zhou, Determination of the Contact Length in Grinding, Annals of CIRP, 1992. 2. Only in Chinese

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C30 Analysis of the Kinematics of Cam and Crank Grinding Contact Information: Dr. Zhixiong Zhou College of mechanical and automotive engineering Hunan University Changsha, 410082 P.R.China Email: [email protected] Abstract: This research was on non-prismatic parts, such as cams and crankshafts . A kinematic simulation model was developed, with regards process stability and geometry of the finished shape. From this simulation a new CNC machine tool was developed and the models were experimentally verified. Key Issues of this Work: Status: Completed Publications of this Work: 2. Only in Chinese

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C31 Pitch Arc Moving Heat Source Model ---- Thermal Modeling of Surface Grinding by Cup Wheel

Contact Information: Professor Bin Lin(1963) School of Mechanical Engineering Tianjin University Tianjin City, P.R. China, 300072 Email: [email protected]: [email protected]: [email protected] Abstract: A moving heat source model of cup wheel surface grinding is built. Three-dimensional quasi-steady temperature field in workpiece without coolant is analyzed and its formula is obtained based on this thermal model and the theory of heat conduction. The theoretical calculation shows that cup wheel surface grinding temperature field takes on non-uniform shape. The result is also helpful to analyses other thermal problems emerged in mechanical operations such as cutting and milling. Key Issues of the Work: • Theoretical Analysis of Surface Grinding Temperature Field by Cup Wheel -----Pitch Arc

Moving Heat source Model • Measuring the surface temperature during cup wheel grinding Status: On-going Publications of this work: 1. B. Lin, H.L. Zhang. 2001, Theoretical Analysis of Surface Grinding Temperature Field by

Cup Wheel, Key Engineering Materials, Vols. 202-203(2001), pp. 93-98. 2. B. Lin, S.H. Chen, H.L. Zhang, J.G. Zhang, Q. H. Yuan, W. J. Guo. 2004, Application of

Pitch Arc Moving Heat source Model in Grinding Temperature Field of Disk Workpiece, Key Engineering Materials, Vols. 256-260(2004), pp. 249-253.

3. B. Lin, Q. H. Yuan, H.L. Zhang, J.G. Zhang, S.H. Chen, W. J. Guo. 2004, Analytic Analysis of Surface Grinding Temperature Field by Cup Wheel, Key Engineering Materials, Vols. 256-260(2004), pp. 254-258.

4. Lin Bin, Imai Kenichiro, Hashimoto Hiroshi. 1998, Surface Grinding Temperature in Ductile Grinding Silicon, 1998 Annals of Association of Precision Engineering in Japan, pp. 326.

5. Lin Bin, Yu Ai-bing, Hu Jun, Xu Yan-shen. 2000, Studies of Surface Grinding Temperature Affected by Different Grinding Ways of Silicon Wafer, Transactions of Tianjin University, Vol. 6, pp. 85-89.

6. Lin Bin, Yu Si-yuan, Xu Yan-shen. 2000, Surface Grinding Temperature of ZrO2 and SiC, Journal of Tianjin University, Vol. 33, pp. 740-742.

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C32 Unsteady-State Grinding Technology---Hard-Brittle Materials Ultraprecision Grinding with Common Abrasive Grinding Wheel

Contact Information: Professor Bin Lin(1963) School of Mechanical Engineering Tianjin University Tianjin City, P.R. China, 300072 Email: [email protected]: [email protected]: [email protected] Abstract: The concept of the unsteady state grinding technology was proposed and compared with conventional grinding technology. Experimental work was performed to prove the existence of the unsteady state in the process of ultra-precision grinding with common abrasive wheel. From the results of the observation of the wheel topography, the whole grinding process in unsteady state was separated into three stages namely cutting by grains peaks, micro-cutting by micro edges of the broken grains and rubbing without material removal. By utilizing the common abrasive wheel newly redressed to grind the finished surface of silicon nitride glut and comparing the finished surface with the damaged surface in SEM patter and surface roughness, the existence of cutting and micro-cutting actions in the unsteady state grinding process was confirmed. Key Issues of the Work: • Theoretical Generalization and Research on Grinding Mechanism • Experimental Studies of Grinding Forces and Force Ratio • Studies on the Surface Quality of Unsteady-state grinding technology Status: On-going Publications of this work: 1. B. Lin, Z.C. Li, Y.S. Xu, J. Hu. Theoretical Generalization and Research on Grinding

Mechanism of Unsteady-state grinding technology, Journal of Materials Processing Technology, Vol. 129(2002), pp. 71-75.

2. Z.C. Li, B. Lin, Y.S. Xu, J. Hu. Experimental Studies of Grinding Forces and Force Ratio of Unsteady-state grinding technology, Journal of Materials Processing Technology, Vol. 129(2002), pp. 76-80.

3. Y.S. Xu, J. Hu, B. Lin, Z.C. Li. Studies on the Surface Quality of Unsteady-state grinding technology, Journal of Materials Processing Technology, Vol. 129(2002), pp. 364-368.

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C33 Optimum Design of Grinding Wheel Topography for High Efficiency Grinding

Contact Information: Dr Yucan Fu College of Mechanical and Electronic Engineering Nanjing Univ. of Aeronautics and Astronautics 29#, Yudao Street, Nanjing, 210016 P. R. China. Tel: +86 25 84895857 Fax: +86 25 84895857 Email: [email protected] Abstract: The optimized topography model can be used to optimize the wheel topography in accordance with machining demands and grinding parameters as well as optimize grinding parameters in accordance with the topography and machining demands. Thus the optimum results can give guidance to the design and fabrication of the grinding wheel as well as the reasonable employment of the grinding wheel in the grinding processes. Key Issues of the Work: • Theoretical optimum model of grinding wheel topography • Design and fabrication of a super abrasive slotted grinding wheel Status: On-going Publications of this work: Y.C. Fu, H.J. Xu, J.H. Xu. Optimization Design of Grinding Wheel Topography for High Efficiency Grinding. Journal of Materials Processing Technology, 2002,129(1): 118-122

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C34 Study on High Efficiency Cooling Technology Aims at Green Manufacturing and its Experiments Contact Information: Dr Yucan Fu College of Mechanical and Electronic Engineering Nanjing Univ. of Aeronautics and Astronautics 29#, Yudao Street, Nanjing, 210016 P. R. China. Tel: +86 25 84895857 Fax: +86 25 84895857 Email: [email protected] Abstract: High efficiency machining technology and GM (green manufacturing) become two key fundamental technologies mainly developed in the field of advanced manufacturing of 21st century. On the basis of research on the thermal effect in machining zone during high efficiency machining, a new idea of high efficiency cooling--cryogenic pneumatic mist jet impinging cooling technology is advanced.. The study will exploit an important research orientation in high efficiency machining for GM. Furthermore, and will enable us solve the workpiece burn problem of the difficult-to-machining materials in high efficiency machining. Key Issues of the Work: • Fundamental heat transfer experiments of enhancing heat transfer through cooling--cryogenic

pneumatic mist jet impinging • The effects of cryogenic pneumatic mist jet impinging cooling in grinding of titanium

alloy(TC4) Status: On-going Publications of this work: 1. H.J. Xu, Y.C. Fu, F.H. Sun, X.P. Xu. Fundamental Studies on Enhancing Heat Transfer in

Grinding Zone during High Efficiency Grinding, Science in China （Series E），2002，32

（3） 2. Y.C. Fu , H.J. Xu , F.H. Sun. Studies on exploiting further the potential of High Efficiency

Grinding. Materials Science Forum, 2004, 471-472, 405-408 3. Y.C. Fu , H.J. Xu A Study on Enhancing Heat Transfer with Jet Impingement in Creep feed

Grinding with Slotted Grinding Wheel. Acta Aeronautica et Astronautica Sinica. (in Chinese)

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C35 Fundamental Studies on Enhancing Heat Transfer in Grinding Zone during High Efficiency Grinding Contact Information: Dr Yucan Fu College of Mechanical and Electronic Engineering Nanjing Univ. of Aeronautics and Astronautics 29#, Yudao Street, Nanjing, 210016 P. R. China. Tel: +86 25 84895857 Fax: +86 25 84895857 Email: [email protected] Abstract: On the basis of research on the thermal action in grinding contact zone during high efficiency grinding, an idea of enhancing heat transfer in grinding zone using high pressure water jet impinging was advanced. Fundamental heat transfer experiments on enhancing heat transfer through high pressure water jet impinging were completed. The maximum speed of jet impinging reaches 110m/s. The experimental results of transient and steady-state experiment prove that the critical heat flux and the heat-transfer coefficient of water jet impinging are 70 and 30 times of the pool boiling respectively. Furthermore, a new grinding fluid supply system was employed to enhance heat transfer in grinding zone by high-pressure water jet impingement during creep feed grinding. The experimental results assure the remarkable cooling effect of high-pressure water jet impinging. Surface temperature of the workpiece can be steadily mantained at an extremely low level that is below 100℃ while the workpiece is serious burn with conventional coolant supply. The study will develop an important research domain in the high efficiency grinding that has great potentialities. The further perfection of this study will not only increase the available material removal rate to a new level, but also solve the workpiece burn problem of the difficult-to-machining materials in high efficiency grinding, which has great technical and economical significance. Key Issues of the Work: • Fundamental heat transfer experiments of enhancing heat transfer through high-pressure

water jet impinging • Analysis on the Temperature Field on Wokpiece Surface Layer in Creep Feed Deep Grinding

with Slotted Grinding Wheel • Creep feed grinding experiment of the enhancing heat transfer in grinding zone with high-

pressure water jet impinging • workpiece surface temperature measurement with the constantan wire-workpiece semi-

natural thermocouple. Status: On-going Publications of this work:

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4. H.J. Xu, Y.C. Fu, F.H. Sun, X.P. Xu. Fundamental Studies on Enhancing Heat Transfer in Grinding Zone during High Efficiency Grinding, Science in China （Series E），2002，32

（3） 5. Y.C. Fu , H.J. Xu , F.H. Sun. Studies on exploiting further the potential of High Efficiency

Grinding. Materials Science Forum, 2004, 471-472, 405-408 6. Y.C. Fu , H.J. Xu A Study on Enhancing Heat Transfer with Jet Impingement in Creep feed

Grinding with Slotted Grinding Wheel. Acta Aeronautica et Astronautica Sinica. (in Chinese)

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C36 New Generation of Monolayer Brazed Diamond Tools with Optimum Grain Distribution Contact Information: Dr Yucan Fu College of Mechanical and Electronic Engineering Nanjing Univ. of Aeronautics and Astronautics 29#, Yudao Street, Nanjing, 210016 P. R. China. Tel: +86 25 84895857 Fax: +86 25 84895857 Email: [email protected] Abstract: A new generational manufacturing technology for diamond tools on brazing process cooperated with optimum distribution of grains is put forward. Monolayer brazed diamond tools with optimum grain distribution are manufactured and their machining performance is investigated through experiments. The testing results show that this series of diamond tools are certain to have super outstanding machining performance, which provides an innovative technology for manufacturing new generation of superbrasive tools. Key Issues of the Work: • A new idea of brazed superabrasive tools with optimum grain distribution is put forward,

whose pith lies in a topography optimization for tools in accordance with different machining demands.

• An innovative technology of manufacturing monolayer diamond tools with optimum grain distribution during brazing process is provided, which can realize an optimum grain distribution on arbitrary complicated tool.

• The size, number, form and distribution characterization of resultant at the brazing interface under different brazing conditions was discovered and the brazing mechanism for diamond was illuminated. High strength chemical metallurgy bonding at the interface without additional heat damage to diamonds is steadily acquired.

• According to the preference principle for manufacture demand, a set of monolayer brazed diamond tools with optimum topography have been developed and experiments are carried out to prove their excellent performance. Compared with monolayer electroplated tools, their machining efficiency and tool life can all increase 10 times, respectively. Compared with multilayer sintered tools, their machining efficiency can boost 10~15 times, and their life can almost reach the sintered ones.

Status: On-going Publications of this work: 1. H.J. Xu, Y.C. Fu, B. Xiao, J.H. Xu. New Generation of Monolayer Brazed Diamond Tools

with Optimum Grain Distribution. Key Eng. Materials，2004，259-260：6-9

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2. B. Xiao, H.J. Xu, Y.C. Fu. Form and Distribution Characterization of Resultant at The Brazing Interface Between Ni-Cr Alloy and Diamond. Key Engineering Materials.2004，259-260：151-153

3. Y.C. Fu, B. Xiao, J.H. Xu and H.J. Xu. Machining Performance of Monolayer Brazed Diamond Tools. Key Engineering Materials.2004，259-260：73-77

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C37 Laser Truing and Dressing of Super-abrasive Grinding Wheels Contact Information: Xuyue Wang School of Mechanical Engineering Dalian University of Technology Dalian, 116023 P. R. China Tel: 86-411-84708422 Fax: 86-411-84708812 Email: [email protected], [email protected] Abstract: Grinding wheels tested in this project are cylindrical, and the circular profile influences greatly the amount of energy absorbed in different incident angles and is thus an important processing parameter. The laser beam, in general, was applied vertically with respect to the surface of the wheel. Different incident positions (one-to-one correspondence with incident angle) applied to the focal area of the wheel impart different levels of energy to the wheel. In our study, energy models were developed that take into account the energy mode of laser energy absorbed/scattered by the cylindrical profile of the wheel. Laser dressing that removes the wheel materials through ablation of the bonding material (resin) to expose cutting grain edges has been tested for aluminum oxide wheels. But, there are still some problems that are not well understood in laser processing of a vitrified CBN grinding wheel. Few studies have dealt with laser processing of the vitrified CBN wheel owing to its thermal properties of bond (ceramic) closed to that of abrasive (CBN). It is not easy to mainly remove the bonding material at the same time to keep grain edges explosives out of bonding. On the other hand, the original laser beam is Gaussian mode, it generates uneven temperature field and it is probably not a selective mode. This features need to be modified or controlled as selective processing mode as expected. A uniform rectangular beam has been modified by means of optical scanning expander, which improves laser-processing homogeneity better than Gaussian mode; but it cannot meet the demands for laser selective truing and dressing. Moreover, a novel technology designed in our works was that energy mode could be adjusted with deformable mirror based on adaptive optical technology. It was assumed that the entire materials absorb the laser energy in accordance with the energy balance equation during processing. By varying parameters, such as incident position, incident energy mode, the optimal parameters were predicted in laser processing of small-vitrified CBN grinding wheels, and the creative processing technique developed was shown to be reliable. In general, a study of energy-mode (including both geometric and mathematical models) adjustment in laser processing a small-vitrified CBN grinding wheel was presented which discussed effects of adjustable methods on energy mode. Three methods were dealt with energy-mode adjustment respectively. The circular profile could naturally modify energy mode/density, the optical scanning expander turned Gaussian beam into a uniform beam, and a novel technique

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of deformable mirror that obtained more controllable energy mode designed for laser selective processing. A predictive model for energy-mode description was developed to enhance laser-processing performance. Status: Ongoing References: None were sent

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C38 Evaluation and Measurement of Surface/Subsurface Crack Damage of Ground Ceramics Contact Information: Professor Si Yuan Yu School of Mechanical Engineering Tianjin University 92 Weijin Road Tianjin 300072 China Tel: 022-87894568(H) Tel: 022-81653845(O) Fax: 022-27403434 Email: [email protected] ,or , [email protected] Abstract: While be ground, ceramic is prone to engender surface/subsurface crack damage layer because of great grinding force and high brittle of the material. The crack damage layer was investigated in this research. In experiment, it is observed that the surface/subsurface crack damage layer consists of three kinds of cracks: surface micro-cracks, surface macro-cracks and subsurface crack system. To evaluate expediently the degree of damage to the machined components, the index of surface/subsurface crack damage--- Dc, is defined. Status: Completed 2004 Publications of my work: 1. S.Y.Yu (1), An experimental study on molecular dynamics simulation in nanometer grinding,

IMechE Conference Transactions CAPE 2000, 155-161 2. S.Y.Yu (2), The experimental study on molecular dynamics simulation in nanometer

grinding ，Proceedings of the Ninth International Manufacturing Conference in China,IMCC’2000,389-390

3. S.Y.Yu(3), Mechanism of Material Removal and Surface Generation by Molecular Dynamics Analysis in Abrasive Processes, Nanotechnology and Procision Engineering, Vol.2 No.2 Jun.2004

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CZ1 Grinding of Ceramic Materials Contact Information: Dr. Frantisek Holesovsky Institute of Production Technology and Management Jan Evangelista Purkyne University Usti nad Labem, 400 96 Czech Republic Email: [email protected] http: www.utrv.ujep.cz Abstract: Ceramic materials can be called as materials of the future. Knowledge about machining of these materials is necessary condition for usage of ceramics in the industry. Key Issues of the Work: • Possibility of grinding of ceramic materials • Influence of process parameters on ground surface quality Status: On-going Publications of This Work: 1. Holesovsky, F., Hrala, M., 2004, Grinding of the Silicon and Nitride Ceramics. In.:

Proceedings 7th International Scientific Conference, Presov, pp. 296-299.

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CZ2 Grinding Intelligent Control System (GICS) Contact Information: Dr. Frantisek Holesovsky Institute of Production Technology and Management Jan Evangelista Purkyne University Usti nad Labem, 400 96 Czech Republic Email: [email protected] http: www.utrv.ujep.cz Abstract: Grinding intelligent control system includes a database creation, mathematical model definitions, control determination and controlled quantities for the continuous control of the process. One of the main issues is also verification of influence of continuous change of speed. Key Issues of the Work: • Monitoring and control of grinding process Status: On-going Publications of This Work: 1. Holesovsky, F., 1996, The Grinding Process Mathematical Modeling and an Expert System.

In.: Proceedings International Manufacturing Conference, Connecticut, Storrs, pp. 50-52. 2. Holesovsky, F., Naprstkova, N., 2003, Automation of the Grinding Machine Working Cycle.

In.: Computer-Aided Systems for Manufacture and Measurement of Machine Elements, Kielce University of Technology, Kielce, pp. 125-134.

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CZ3 Integrity of Ground Surface Layer Contact Information: Dr. Frantisek Holesovsky Institute of Production Technology and Management Jan Evangelista Purkyne University Usti nad Labem, 400 96 Czech Republic Email: [email protected] http: www.utrv.ujep.cz Abstract: Integrity of ground surface layer is composed from surface roughness, profile of ground surface, geometric fidelity, hardness of surface layer and residual stress. All these factors have an influence on loading capacity of the surface. Integrity is studied from many points of view, but all of them have some influence on quality of ground surface - coolant, cutting conditions a parameters etc. Key Issues of the Work: • Influence of coolant on quality of ground surface • Influence of process parameters on grinding and final surface properties • Loading capacity of ground surface, exchange into surface after loading Status: On-going Publications of This Work: 1. Trmal, G. J., Holesovsky, F., 2001, Wave Shift and Its Effect on Surface Quality in Super-

abrasive Grinding, Journal of Machine Tools and Manufacture, Vol. 41, pp. 979-989. 2. Holesovsky, F., Hrala, M., 2004, Integrity of Ground Cylindrical Surface, Journal of

Materials Processing Technology, Vol. 153-154, pp. 714-721. 3. Holesovsky, F., Hrala, M., 2000, Analyse of Influence of New Abrasive Materials on Ground

Surface. In.: Proceedings 7th International Conference on Flexible Technologies, Novi Sad, Yugoslavia, pp. 211-212.

4. Holesovsky, F., 2001, Grinding Process and Its Influence to Surface Integrity. In.: Proceedings International Conference AMPT´01, Madrid, Spain, pp. 587-596.

5. Holesovsky, F., Hrala, M., Novak, M., 2003, Position of Grinding in Field of High Precision Technologies. In.: Proceedings 2nd International Congress ICPM, Prague, pp.129-137.

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CZ4 High Efficiency Deep Grinding (HEDG)

Contact Information: Mr. Michal Hrala Institute of Production Technology and Management Jan Evangelista Purkyne University Usti nad Labem, 400 96 Czech Republic Email: [email protected] http: www.utrv.ujep.cz Abstract: HEDG has been developed from a combination of high-speed and creep grinding techniques and is classified as deep grinding at high workspeed and very high removal rates. The research aim is to establish the thermal and physical conditions for high efficiency grinding (HEDG) and to develop a strategy to achieve damage free grinding at the highest possible stock removal rates. Key Issues of the Work: • Thermal limitation to material removal by grinding • Measurement of surface temperature during the grinding • Simulation of grinding process by means of the mathematical model • Choice of the best cutting conditions for HEDG process Status: Preliminary Stage Publications of This Work: 1. Rowe, W. B., 2001, Thermal Analysis of High Efficiency Deep Grinding, International

Journal of Machine Tools & Manufacture 41, pp. 1-19. 2. Tawakoli, T., 1993, High Efficiency Deep Grinding, VDI-Verlag and Mechanical

Engineering Publications. 3. Rowe, W. B., Morgan, M. N., Batako, A., Jin, T., 2003, Energy and Temperature Analysis in

Grinding, In.: Proceedings 6th International Landamap Conference, Keynote paper, Huddersfield.

4. Rowe, W. R., Jin, T., 2001, Temperatures in High Efficiency Deep Grinding, Annals the CIRP, Vol. 50, pp. 205-208.

5. Morgan, M. N., Rowe, W. B., Batako, A., 2003, Energy Limitations in HEDG and Conventional Grinding, In.: Proceedings 6th International Symposium on Advances in Abrasive Technology ISAAT.

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CZ5 Surface Texture after Grinding of Ceramic Materials Coated by Thermal Spraying and Its Influence on the Friction Contact Information: L.Bumbalek Department of Technology Faculty of Mechanical Engineering Brno University of Technology Czech Republic Email: [email protected] Abstract: Very important technology of the last years is the technology of coating ceramic materials by thermal spraying. The coated surface is ground and the texture of such a surface differs from the sintered one. Also functional properties are different. In the contribution there are introduced the grinding results of ceramic materials coated by thermal spraying i.e. the cutting forces, surface roughness when using different wheels (SiC, CBN, DIA). The results are compared with grinding of sintered ceramics. The ceramics materials coated by thermal spraying were tested to the friction and as bioactive materials in orthopaedics, stomatology and surgery. In this case there are required the abilities to create bond with vital connection tissue. The grinding tests on the ceramic materials coated by thermal spraying demonstrated, that the process of separation of these materials proceeds as micro-brittle fracture, which course is influenced first of all by properties of these materials. There is the porosity, cracks, eventually other defects in upper layer. The process of coating by thermal spraying produces the changes in coated layer properties. All these changes are shown in appearance and texture of machined surface. Therefore, there is necessary to do the checking of properties of coated ceramic layer after spraying. Without this checking the defects of upper layer can influence the functional properties of component finished by thermal spraying. From the grinding wheel point of view there are as optimal the diamond grinding wheels. Publications of this Work: 1. Mehlhose,J., Schneeweiss,K.:1996: Wirtschaftliches Schleifen von Siliciumnitrid, Teil I ,II,

Werkzeuganswahl, Keramikbearbeitung, IDR 1/96, 2/96. 2. Bumbalek, B., Novak, Z., Vala, P.: 1989: Evaluation of Surface Roughness of Coated

Ceramics After Grinding, Research report VU 070 Brno, (In Czech language) 3. Bumbalek, L.: 2000: The influence of machined surface on friction and wear of ceramic

materials Coated by thermal spraying, Habilitate work, Technical university Brno, 2000. (In Czech language)

4. Ambroz,O.: 2002: International Scientific Congress INTERANTIKOR, 2002.

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GB1 Grinding Processes and their Effect on Surface Integrity Contact Information: Paul Comley Cranfield Precision 90 Central Ave Wharley End Cranfield Bedfordshire MK 43 0JR UK Email: [email protected] http:www.cranfieldprecision.com Abstract: The introduction of high performance grinding machines in combination with the latest superabrasive technology has the potential to impact significantly on existing process chains. High Efficiency Deep Grinding (HEDG) can now compete with conventional cutting processes and proves the potential for improved surface integrity, surface finish and form accuracy. It is shown that the same grinding machine can be used to generate superfinished surfaces with roughness values as low as 10nm Ra. Thus, using a single machine tool and a single set-up, exceptionally high stock removal; rates are achievable in a roughing cycle followed by superfinishing to generate the required surface characteristics and profile.

Key Issues of the Work: • HEDG regime for the grinding of steel • Development of PVD Coatings for Thermal Measurement in Cylindrical Grinding • The effect of Grinding on Surface Integrity • Superfinish regime for grinding of Steel Status: Complete Publications of this work: 1. Paul Comley, D.J. Stephenson, J. Corbett, 2002, Towards a More Efficient Grinding Process,

Proceedings of 5th International Conference on Behaviour of Materials in Machining, pg 303-306.

2. Paul Comley, 2005, Grinding Processes and their Effect on Surface Integrity, PhD Thesis Cranfield University, Expected early 2005

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GB2 High Efficiency Deep Grinding and the Effect on Surface Integrity Contact Information: Paul Comley Cranfield Precision 90 Central Ave Wharley End Cranfield Bedfordshire MK 43 0JR UK Email: [email protected] http:www.cranfieldprecision.com Abstract: The introduction of high performance grinding machines in combination with the latest superabrasive technology has the potential to impact significantly on existing process chains. High efficiency deep grinding (HEDG) with its high material removal rates can now compete with conventional cutting processes whilst maintaining surface integrity and surface finish requirements.

Key Issues of the Work: • The HEDG regime for Cylindrical Plunge Grinding • Development of PVD Coatings for Thermal Measurement in Cylindrical Grinding • The effect of Grinding on Surface Integrity Status: Complete Publications of this work: Paul Comley, D.J. Stephenson, J. Corbett, 2004, High Efficiency Deep Grinding and the Effect on Surface Integrity, Advances in Abrasive Technology, Vol VI, pg 207-212. Forth coming Publications of this work: 1. Paul Comley, 2005, Grinding Processes and their Effect on Surface Integrity, PhD Thesis

Cranfield University

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GB3 The Performance and Wear Behaviour of Diamond Fibre Grinding Wheels when Grinding Glass Contact Information: Paul Comley Cranfield Precision 90 Central Ave Wharley End Cranfield Bedfordshire MK 43 0JR UK Email: [email protected] http:www.cranfieldprecision.com Abstract: Diamond coated fibres have been produced by a hot filament CVD technique, where the surface of the fibres has a faceted structure making them suitable for use as an abrasive medium. Grinding trials to determine the performance of a metal bonded diamond fibre grinding wheel have been carried out using a ‘state of the art’ machining centre developed for the high precision ductile regime grinding of optics. Further work has been undertaken using a single fibre placed radially in a titanium disc to assess wear. Ductile ground surfaces were produced in BK7 glass with a surface roughness figure of 70nm Ra, and less than 2μm sub-surface damage. The wear behaviour of the single fibre mounted in a disc wheel was monitored. Measurements showed that the initially sharp leading edge broke down to form a chamfered wear face, the profile produced by the fibre remaining similar.

Diamond fibre grinding wheels have been shown to be capable of ductile grinding. These initial trials suggest that diamond fibres have the potential for longer wheel life, when grinding in the ductile region, compared with existing resin bond wheels. Key Issues of the Work: • Development of Diamond Fibre Grinding Wheels for use in the manufacture of optical

components Status: On-going Publications of this work: 1. P. Comley, N. P. Smith, T. R. A. Pearce, D. J. Smith, M. N. R. Ashfold, 2004, The

Performance and Wear Behaviour of Diamond Fibre Grinding Wheels when Grinding Glass, Advances in Abrasive Technology, Vol VI, pg 245-250.

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GB4 - Standard Grinding Wheel Assessment Method to Support a Sophisticated Grinding Knowledge-Based System

Contact Information: Professor Paul Shore McKeown Chair of Ultra-Precision Technologies School of Manufacturing and Industrial Science Manufacturing Systems Building 50, Cranfield UniversityUK Tel: +44 (0)1234 754629 Email: [email protected] Abstract: An important issue when optimising production-grinding cycles is the selection of the grinding wheel. However, there exist today no standard methods for assessing the purposefulness of a specific grinding wheel for a given application. This project details an assessment method that generates "performance benefits" data of grinding wheels. The format of the data is designed to support a grinding knowledge based system (KBS). This KBS system is used to advise optimum grinding cycles for specified mass production systems and workpieces. From the standpoint of an "end-user" the general need for standard wheel testing procedures is advocated. The method proposed in this project is found to be useful for assessing abrasive products from the viewpoint of a major “end-user” of such products. Clearly, the method discussed within this paper has been developed in mind of precision cylindrical grinding operations. However, the researcher considers the advocated testing method to be a realistic basis from which to develop some industrial and academically agreed basis for describing grinding wheel “performance benefits”. This work is part of a broader Intranet-based system for grinding cycle optimisation, which considers grinding cycle design, machine tool and workpiece, as well as the grinding wheel selection. Key Issues of the Work: In order to make any grinding KBS a precise and real time “advice giving” tool it must include details of the available grinding wheels including their operating characteristics and their “performance benefits” Status: Completed Publications of this work: 1. P. Shore, O. Billing and V. Puhasmagi, Standard Grinding Wheel Assessment Method to

Support a Sophisticated Grinding Knowledge-Based System, Proc. of Advances in Abrasive Technology VI, ISAAT 2003, Bristol, UK.

2. P. Shore, et al., Intranet Based Systems for Grinding Cycle Optimisation, Proc. of European Conference in Grinding, Aachen, Germany, 2003

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GB5 Machinability of Burn Resistant Titanium Contact Information: David Aspinwall School of l Engineering (Mechanical & Manufacturing Engineering) University of Birmingham Edgbaston, Birmingham B15 2TT United Kingdom Email: [email protected] Abstract: Experimental studies of surface and creep feed grinding are in progress using a flexible grinding centre with both conventional silicon carbide and superabrasive wheel products. Key Issues of the Work: • Generation of machinability / surface integrity data including residual stress and fatigue

analysis • Measurement of cutting temperature using implanted thermocouple techniques • Correlation of workpiece surface topography with fatigue performance • Fluid application and performance evaluation Status: On-going Publications of this work: 1. Novovic, D., Dewes, R.C., Aspinwall, D.K., Voice, W., Bowen, P., 2004, The effect of

machined surface topography and integrity on fatigue life, International Journal and Machine Tools and Manufacture, Vol. 44 (2-3), pp. 125-134.

2. Novovic, D., Aspinwall, D.K., Dewes, R.C., Voice, W., Bowen, P., 2003, The surface integrity of a burn resistant titanium alloy (Ti-25V-15Cr-2Al-0.2C wt%) after high speed milling and creep feed grinding, Proceedings of the 10th World Conference on Titanium – Ti2003 Science and Technology, Wiley-VCH 5, pp. 2817-2824.

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GB6 Machinability of Gamma TiAl Intermetallic Contact Information: David Aspinwall School of l Engineering (Mechanical & Manufacturing Engineering) University of Birmingham Edgbaston, Birmingham B15 2TT United Kingdom Email: [email protected] Abstract: The work extends that previously undertaken on a grain refined titanium aluminide and involves surface and creep feed grinding experimentation using a flexible grinding centre. Both conventional and superabrasive wheels are under evaluation. Key Issues of the Work: • Generation of machinability data in particular workpiece surface integrity effects • Measuring of cutting temperature using implanted thermocouple techniques Status: On-going

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GB7 Feasibility Study on the Point Grinding of Nickel Based Superalloys Contact Information: David Aspinwall School of l Engineering (Mechanical & Manufacturing Engineering) University of Birmingham Edgbaston, Birmingham B15 2TT United Kingdom Email: [email protected] Abstract: Experimental work completed on the use of superabrasive (diamond & CBN) electroplated grinding points for the profiling and slotting of nickel based superalloy (Inconel 718 & Udimet 720). Key Issues of the Work: • Generation of machinability / surface integrity data including residual stress • Point life and wear • Fluid application and performance evaluation Status: Completed Publications of this work: 1. Aspinwall, D.K., Dewes, R.C., Burrows, J.M., Paul, M., 2001, High speed machining (HSM),

system design and experimental results for grinding / HSM and EDM / HSM, Annals of CIRP, 50(1), pp. 145-148.

2. Soo, S.L., Ng, E.G., Dewes, R.C., Aspinwall, D.K., Burrows, J.M., 2002, Point grinding of nickel-based superalloys, Industrial Diamond Review, Vol. 62, No. 593, pp. 109-116.

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GB8 Optimization of Electrochemical Grinding Process for Titanium Alloys Contact Information: Joseph McGeough Regius Professor of Engineering University of Edinburgh Division of Engineering (Mechanical) Sanderson Building Edinburgh, EH9 3JL United Kingdom Tel +1 131-650-6554 ( Fax ) email: [email protected] http://www.ed.ac.uk Abstract : Titanium poses difficulties for conventional manufacturing owing to its thermal conductivity that can cause high thermal tool loads, and its high reaction affinity with atmospheric oxygen. An alternative technique , electrochemical grinding, is discussed here in which mechanical and electrochemical removal are discussed. Optimisation of the process to secure appropriate machining variables for acceptable surface quality and rate of metal removal is investigated. Development of artificial intelligence techniques for a knowledge - based system arising from these results is discussed. A Manufacturing Target Diagram is used to provide a general overview of the results obtained. Key Issues of the Work: • Electrical conductivity of the grinding wheel, from arbor to abrasive Status: Completed Publications of this Work: 1. Clapp, J. A. McGeough, H. A. Senbel, A. De Silva, "Optimization of electrochemical

grinding process for titanium alloys", Institution of Mechanical Engineers (IMechE) Conference Transactions, 16th International Conference on Computer-Aided Production Engineering( CAPE 2000), pp. 343 to 351(2000).

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GB9 In Process Control of Grinding Wheel Surface using Intelligent Grinding and Dressing Contact Information: Dr T.M.A. Maksoud School of Technology Department of Mechanical Engineering and Technology Management University of Glamorgan Pontypridd, Mid Glamorgan CF37 1DL, Wales, UK Tel: 0044 - 1443 - 482219 Fax: 0044 - 1443 - 482231 Email: [email protected] Abstract: In process control of grinding wheel surface, associated with controlled automatic dressing of grinding wheels are the main themes of investigation. Novel HRPS (high response pressure sensor) and neural net work package are used to control the grinding operations. Key Issues of the Work: • In process intelligent control of grinding and dressing operation. Status: On-going Publications of this work: 1. Maksoud T.M.A., Ahmed M.R. and Koura M.M., 2003, Applications of Artificial

Intelligence to Grinding Operations Via Neural Networks. International Journal of Machining, Science, and Technology, Vol. 7, No. 3, pp. 361-389.

2. T. M. A. Maksoud and M. R. Atia. 2004. ‘Review of Intelligent Grinding and Dressing Operations’. Journal of Machining Science and Technology, Vol. 8, No. 2, pp. 263-276.

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GB10 Intelligent Monitoring and Optimisation for Aerospace Material Grinding Contact Information: Dr Xun Chen School of Mechanical, Materials and Manufacturing Engineering University of Nottingham Nottingham NG7 2RD UK. Email: [email protected]: www.nottingham.ac.uk/%7Eepzxc/AATG/ Abstract: Understanding the interaction among the grinding parameters, associated tooling and equipment is vital to grinding cost and quality. In this project the turbine blade grinding is monitored by various sensors and relevant techniques. The grinding cost and quality are optimised by comprehensive analysis based on the measured information such as forces, AE and wheel wears. Multivariate analysis and multi-objective optimisation method were developed to evaluate the total cost caused by various wheels. Feature extraction and fuzzy pattern recognition were used for grinding burn detection. Successful rate was 92%. Key Issues of the work: • Multi-sensor techniques for grinding monitoring • Signal processing in the time-frequency domain • Artificial intelligence for defect identification. Status: On-going. Publications of this work: 1. Q. Liu, X. Chen, N. Gindy, Fuzzy Pattern Recognition of AE signals for Grinding Burn,

International Journal of Machine tools & Manufacture, in press. 2. X. Chen, Q. Liu, Exploration of superabrasive wheels in high efficiency precision grinding,

InterTech 2003, 28 July ~ 1 August 2003. 3. X. Chen, The Sharpness of Grinding Wheels: an Important Measure of Grinding Behaviour,

the Journal of Engineering Manufacture, Proceedings of IMechE, 2002, Vol.216, B2, 829-832.

4. Q. Liu, Y. Wang, M. Geldart, X. Chen, N. Gindy, Condition Monitoring Systems in the Grinding Process, International Conference on Mechanical-Electronic Engineering and Computer Application, 1- 4 November 2002, Hong Kong.

5. Q. Liu, Y. Wang, M. Geldart, X. Chen, N. Gindy, The developing status of condition monitoring systems in grinding, Proceedings of the 18th National Conference on Manufacturing Research, 10~12 September 2002, 261-265. Professional Engineering Publishing Ltd.

6. X. Chen, Compliance of Grinding System and Automatic Dwell Control, Proceedings of the 7th Chinese Automation & Computer Science Conference in the UK, 22 September, 2001, 199-204, Pacilantic International Ltd.

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GB11 Knowledge Support Systems for High Efficiency Precision Grinding Contact Information: Dr Xun Chen School of Mechanical, Materials and Manufacturing Engineering University of Nottingham Nottingham NG7 2RD UK. Email: [email protected]: www.nottingham.ac.uk/%7Eepzxc/AATG/ Abstract: Effective knowledge management in manufacture relies on a properly structured system, particularly for a complex technology like grinding. The analysis was focusing at the key elements to be communicated within a manufacturing environment. A suitable structure was proposed for the development of a grinding knowledge management system. This provides better information support for engineers to improve grinding performance. An internet based monitoring system is developed for decision support. Key Issues of the work: • Investigation of grinding knowledge structure • Intelligent knowledge support system • Grinding process modelling • Remote decision support Status: On-going. Publications of this work: 1. X. Chen, T. Limchimchol, S. Hussain, Internet Based Machining Process Monitoring,

Proceedings of the 4th International Conference on e-ENGDET, 2004, pp.401-407. Professional Engineering Publishing Ltd.

2. X. Chen, Systematic Consideration of Grinding Process Monitoring, Proceedings of the 8th Chinese Automation & Computer Science Conference in the UK, 21 September 2002, 175-178, Pacilantic International Ltd.

3. X. Chen, Knowledge Structure Issues for Manufacturing Technology, Proceedings of the 18th National Conference on Manufacturing Research, 10~12 September 2002, 261-265. Professional Engineering Publishing Ltd.

4. X. Chen, W. B. Rowe, Modelling Surface Roughness Improvement in Grinding, the Journal of Engineering Manufacture, Proceedings of IMechE, 1999, Vol.213, No.B1, Part B. 93-96.

5. Xun Chen, D. R. Allanson, W. Brian Rowe, Life Cycle Model of the Grinding Process, Computers in Industry, 1998, v.36, 5-11.

6. X. Chen, W. B. Rowe, B. Mills, D. R. Allanson, Analysis and Simulation of the Grinding Process - Part IV, Effects of Wheel Wear, International Journal of Machine Tools & Manufacture, 1998, Vol.38, No.1-2, 41-49.

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GB12 Characterisation of Wheel Loading and Feasibility Study on Laser Cleaning Contact Information: Dr Xun Chen School of Mechanical, Materials and Manufacturing Engineering University of Nottingham Nottingham NG7 2RD, UK. Email: [email protected]: www.nottingham.ac.uk/%7Eepzxc/AATG/ Abstract: The research applies laser cleaning technique to maintain a sharp cleaning grinding wheel surface so as to achieve high efficiency grinding. Exciting results have demonstrated that laser cleaning is feasible for grinding wheel maintenance. It has proved that the material removal rate could be increased by more than 30% when the laser cleaning technique was applied. It was found that in a laser cleaning process the loaded chips on the grinding wheel surface could be removed by chip fusion, thermal expulsion and evaporation under suitable laser energy flux. By using a laser cleaning model, the suitable laser energy flux can be selected to achieve effective wheel cleaning without damaging the wheel materials. Key Issues of the work: • To understand the mechanism of materials removal using laser cleaning techniques. • To explore laser cleaning methods for removing loaded chips without deteriorating wheel

cutting ability. Status: Feasibility study has completed (2004) and the on-going project continues towards to integration of dressing and cleaning. Publications of this work: 1. X. Chen, Z. Feng, Energy transfer of laser cleaning grinding wheels, Proceedings of the 2nd

International Conference on Manufacturing Research ICMR2004, 6-11. 2. X. Chen, Z. Feng, I. Pashby, Study on laser cleaning Al2O3 grinding wheel, Key Engineering

Materials, 2004, v.257-258, 359-364. 3. X. Chen, Z. Feng, I. Pashby, Comparison of Laser Cleaning of Al2O3 and CBN Grinding

Wheels, Key Engineering Materials, 2004, v.257-258, 365-370. 4. Y. Liu, X. Chen, Study on Abrasive Water Jet Cutting for Granite, Key Engineering

Materials, 2004, v.257-258, 527-532. 5. Xun Chen, Zhengming Feng, Effectiveness of Laser Cleaning for Grinding Wheel Loading,

Key Engineering Materials, v.238-239, n.3., 2003, 289-294. 6. X. Chen, Z. Feng, Grinding Performance under Laser Cleaning, 3rd Int. Conf. and Exhibition

on Design and Production of Die and Molds, 7th Int. Symposium on Advances in Abrasive Technology, June 2004, 317-324.

7. X. Chen, Z. Feng, I. Pashby, Al2O3 Grinding Wheel Cleaning using Nd:YAG Laser, 1st International Conference on Manufacturing Research, September 2003, 27-31.

8. X. Chen, G. Thomson, Z. Feng, Grinding Wheel Cleaning Using CO2 Laser, the 17th National Conference on Manufacturing Research, 4 ~ 6 September 2001, 161-166.

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GB13 Image Analysis for Grinding Wheel Loading Detection Contact Information: Dr Xun Chen School of Mechanical, Materials and Manufacturing Engineering University of Nottingham Nottingham NG7 2RD, UK. Email: [email protected]: www.nottingham.ac.uk/%7Eepzxc/AATG/ Abstract: Grinding wheel loading is one of most common problems in grinding operation, particularly for aerospace materials. Serious wheel loading may cause grinding chatter or thermal damage. Wheel loading will blunt the abrasive grains, thus, directly affecting the grinding efficiency and dimensional accuracy of the finished parts. Therefore, grinding wheel loading should be monitored. The image analysis technique developed in the project provides a new way to quantitatively measure wheel loading situation. This provides better information for engineers to improve grinding performance. Key Issues of the work: • To investigate wheel loading under different grinding conditions. • To characterise wheel loading using digital image analysis techniques. Status: On-going. Publications of this work: 1. Z. Feng, X. Chen, Image Processing of Grinding Wheel Surface, submitted for publication.

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GB14 Intelligent AE Feature Extraction for Grinding Monitoring Contact Information: Dr Xun Chen School of Mechanical, Materials and Manufacturing Engineering University of Nottingham Nottingham NG7 2RD, UK. Email: [email protected]: www.nottingham.ac.uk/%7Eepzxc/AATG/ Abstract: Acoustic emission (AE) has been introduced for machining monitoring for several years. Most applications were limited in the AE RMS monitoring. Features of AE were less explored due to their complicated relationships to machining processes. The project intends to identify the relations between different AE features and machining process phenomena, grinding in particular. Different material removal mechanism and tool failures were examined in relation to AE features. A method to monitor wheel wear and material thermal damage during grinding process was developed. Feature extraction of acoustic emission for monitoring materials processing is the key issue of the project. Key Issues of the work: • Identifying the features of grinding acoustic emission. • Relationship between grinding mechanism and AE • Development of an AE monitoring system for grinding Status: On-going. Publications of this work: 1. Q. Liu, X. Chen, N. Gindy, Fuzzy Pattern Recognition of AE signals for Grinding Burn,

International Journal of Machine tools & Manufacture, in press.

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GB15 Control of Waveshift in Cylindrical Grinding Contact Information: Dr Thomas Pearce Institute of Grinding Technology RAMP Laboratory University of the West of England, Bristol Frenchay Campus, Coldharbour Lane, Bristol BS16 1QY UK Tel: +44 (0) 117 32 82654 Email: [email protected] Abstract: A grinding wheel, even after truing and dressing, will always have some residual eccentricity. During grinding this will produce waviness on the ground surface with the wavelength corresponding to once per revolution of the wheel. During spark-out at the end of the grinding cycle, the roundness obtained will depend on the way in which the waviness pattern produced by the wheel eccentricity overlaps in consecutive revolutions. Waveshift is defined as a measure of the phase shift between the waviness produced on the workpiece in successive revolutions. It is calculated as follows. The wheel rpm is divided by the work rpm. The resulting ratio is then subtracted from the next highest integer. The remainder is known as the waveshift and represents the way that waviness produced by wheel run-out overlaps from one workpiece revolution to the next. An exact integer ratio of rpm gives a waveshift of 0, in which the waviness over successive workpiece revolutions is in phase. This leads to maximum values of roundness errors that are equal to the wheel run-out, regardless of the amount of spark-out. The overlapping effect from non-integer ratios reduces the roundness errors, particularly during spark-out. Key Issues of the Work: • Wheel run-out and balance • Wheel and component rpm ratio (waveshift) • Monitoring and acoustic emission measurement Status: Project completed 2004 Publications of this work: 1. T R A Pearce, D C Fricker, The effect of wheel run-out and waveshift on regenerative chatter,

ISAAT 2004, pp 289-294, Bursa, Turkey, June 2004. 2. D C Fricker, A Speight, T R A Pearce, The modelling of roundness in plunge cylindrical

grinding to incorporate waveshift and external vibration effects, to be submitted to Proc I Mech E, Part B: J. Engineering Manufacture 2005.

3. Trmal, G. J. and Holesovsky, F., Waveshift and its effect on surface quality in super-abrasive grinding, International Journal of Machine Tools & Manufacture, 2001, 41, 979-989.

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GB16 CVD Diamond Fibres in Wheels Contact Information: Dr Thomas Pearce Institute of Grinding Technology RAMP Laboratory University of the West of England, Bristol Frenchay Campus, Coldharbour Lane, Bristol BS16 1QY UK Tel: +44 (0) 117 32 82654 Email: [email protected] Abstract: Diamond coated fibres are produced by a hot filament chemical vapour deposition technique. They have a faceted surface structure with a high facet density, which suggests suitability for abrasive processes. For an initial evaluation, small grinding wheels containing such fibres were manufactured with the fibres placed in a radial orientation. One wheel contained a single fibre, the other contained multiple fibres. The single diamond fibre wheel was used first to evaluate the potential for ductile grinding of glass. A ductile-to-brittle transition was found, occurring at a depth of cut of ~1 μm over a range of feed rates. The multiple diamond fibre wheel was then used to grind an area, using parameters identified by the single fibre tests. Microstructural analysis revealed that material removal was predominantly in the ductile mode. Further evaluation was carried out using a full scale metal bond wheel with random orientation of the fibres. Tests on glass produced ductile ground surfaces having less than 2 μm sub-surface damage, with no measurable wheel wear. Key Issues of the Work: • Demonstrating the capability of diamond fibres to produce ductile grinding in brittle

materials • Material removal rates and wheel wear rates Status: Two projects completed, funding being sought for a third project to investigate the effect of changing diamond fibre properties. Publications of this work: 1. P G Partridge, A J Fookes, E D Nicholson, T R A Pearce and G Meaden, Nanoscale ductile

grinding of glass by diamond fibres, Journal of Materials Science, 31, 5051-5057, 1996. 2. P G Partridge, A J Fookes, E D Nicholson, T R A Pearce and G Meaden, Nanoscale grinding

of ceramics by diamond fibres, Diamond & Related Materials, 6, 893-897, 1997. 3. N.P. Smith, M.N.R. Ashfold, D.J. Smith and T.R.A. Pearce, Manufacture and performance of

diamond-coated thermocouples, Diamond & Related Materials, 8, 956-960, 1999. 4. N P Smith, D J Smith, T RA Pearce, M N R Ashfold, The ductile grinding of glass using

diamond fibres oriented radially in a grinding wheel, Proc I Mech E, Part B: J. Engineering Manufacture, 217, pp387-396, 2003.

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5. P Comley, N P Smith, T RA Pearce, D J Smith, M N R Ashfold, The performance and wear behaviour of diamond fibre grinding wheels when grinding glass, International Symposium on Advances in Abrasive Technology, Bristol, 2003 (published in Key Engineering Materials, 257-8, 245-250, 2004).

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GB17 Chatter Vibration & Resonance Contact Information: Dr Thomas Pearce Institute of Grinding Technology RAMP Laboratory University of the West of England, Bristol Frenchay Campus, Coldharbour Lane, Bristol BS16 1QY UK Tel: +44 (0) 117 32 82654 Email: [email protected] Abstract: A tap test is used to measure the vibration characteristics of grinding machines, in order to identify resonant frequencies and susceptibility to chatter. Many measurements have been made of both research and production machines. The measurements are used to identify machine speeds that will minimise vibration effects. Future research will be aimed at new machine designs that will maximise stiffness and damping and so reduce susceptibility to vibration effects. Key Issues of the Work: • Machine stiffness and damping • Resonant frequencies and stability boundaries Status: On-going Publications of this work: None

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GB18 Reduction of Lobing in Centreless Grinding Contact Information: Dr Thomas Pearce Institute of Grinding Technology RAMP Laboratory University of the West of England, Bristol Frenchay Campus, Coldharbour Lane, Bristol BS16 1QY UK Tel: +44 (0) 117 32 82654 Email: [email protected] Abstract: The research concerns the growth and decay of lobes during centreless grinding. Previous methods of analysing stability have now been extended to generate complete stability diagrams encompassing the entire practical range of machine set-up angles. These diagrams indicate that by varying the set-up angles in a prescribed manner during grinding, rapid rounding of arbitrarily lobed components can be achieved. This is verified via time-domain simulation. A novel method of predicting the lobe growth and decay during centreless grinding has also been developed. The method considers the locations of the three points of contact between a lobed workpiece and the regulating wheel, the support plate and the grinding wheel. A unique circle can be drawn through these three points. The centre and radius of this circle vary continually as the workpiece rotates, in a manner dependent upon the workpiece profile and the set-up angles. An above average instantaneous radius leads, via machine stiffness, to correspondingly larger grinding force and so to an increased instantaneous depth of cut. If this occurs when the trough of a lobe is being ground, the trough will become deeper, and lobe growth will result. By contrast, if the instantaneous radius is below average when the trough is being ground, the lobe will decay. From this simple geometric consideration, the rates of decay and growth of a range of numbers of lobes have been calculated, across a wide range of set-up angles. The results agree well with those obtained using the previous methods. Key Issues of the Work: • Growth and decay rates of lobes in centreless grinding • Varying set-up angles to improve rounding rates Status: Two dimensional model developed and validated, with funding being sought to develop a three dimensional model Publications of this work: 1. A J L Harrison, T R A Pearce, Prediction of lobe growth and decay in centreless grinding

based on geometric considerations, Proc I Mech E, Part B: J. Engineering Manufacture, 216, pp1201-1216, 2002.

2. A J L Harrison, T RA Pearce, Reduction of lobing in centreless grinding via variation of set-up angles, International Symposium on Advances in Abrasive Technology, Bristol, 2003 (published in Key Engineering Materials, 257-8, 159-164, 2004)

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GB19 “A NEW GRINDING REGIME”, Thermal Limitations to Material Removal by Grinding Contact Information: Professor David Stephenson School of Industrial & Manufacturing Science Cranfield University Cranfield MK43 0AL UK Tel: +44 (0)1234 754751 Fax: +44 (0)1234 751172 Email: [email protected] http://www.cranfield.ac.uk/sims/mem/dave_s/dave_home.htm Abstract: The aim of this work is to establish the thermal and physical threshold conditions for high efficiency deep grinding (HEDG) and hence develop a strategy to achieve damage free grinding at the highest possible stock removal rates.

The principal objectives are:

• Develop and validate thermal models for HEDG. • Develop improved methods for temperature measurement during grinding. • Identify the process conditions to achieve low grinding zone temperatures. • Investigate coolant delivery strategies for optimum cooling efficiency and wheel life. • Investigate the upper limits of the HEDG regime. • Develop a control strategy, which can be used for continuous monitoring of HEDG to ensure

optimum surface integrity, together with the most cost effective processing conditions. Status: 36 month project – ends Feb 05 Publications of this work: 1. T Jin, D J Stephenson and W B Rowe, 'Estimation of the convection heat transfer coefficient

of coolant within the grinding zone', Proc. I.Mech.E Vol. 217 Part B, Journal of Engineering Manufacture, 2003, pp. 397-407.

2. P Comley, D J Stephenson and J Corbett, 'High Efficiency Deep Grinding and the Effect on Surface Integrity', ISAAT 2003, 6th Int. Symposium on Advances in Abrasive Technology, 18-20 Nov. 2003, Bristol.

3. T Jin and D J Stephenson, ‘Effects of grinding fluids in High Efficiency Deep Grinding’, Grinding and Abrasives Magazine, Aug/Sept, 2002, pp 4-6.

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GB20 Nanogrinding Contact Information: Professor David Stephenson School of Industrial & Manufacturing Science Cranfield University Cranfield MK43 0AL UK Tel: +44 (0)1234 754751 Fax: +44 (0)1234 751172 Email: [email protected] http://www.cranfield.ac.uk/sims/mem/dave_s/dave_home.htm Abstract: This EU funded project is looking to develop improved grinding technology for the manufacture of free form optical surfaces. The Cranfield research is investigating the application of ELID technology for optimum grinding efficiency. This involves both monitoring of the process and undertaking basic electrochemical studies to understand the mechanism of ELID and how best the process can be optimized and controlled. New types of ELID system are being designed and these will be integrated into a new ultra precision grinding machine. Status: End date Dec 05 Publications of this work: None yet

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GB21 Optimisation of Process Chains for the Superfinishing of Bearing Materials Contact Information: Professor David Stephenson School of Industrial & Manufacturing Science Cranfield University Cranfield MK43 0AL UK Tel: +44 (0)1234 754751 Fax: +44 (0)1234 751172 Email: [email protected] http://www.cranfield.ac.uk/sims/mem/dave_s/dave_home.htm Abstract: The current manufacturing route for spherical bearings involves turning, grinding, honing and polishing operations which result in a final surface finish in the region of 25nm Ra. A recent development, has been the concept of using an additional finishing process based on electrolytic in-process dressing (ELID) grinding/lap-polishing. It is proposed to ELID grind following the existing polishing process with the intention of reducing surface roughness down to below 10nm Ra. Such an improvement in surface finish should provide a significant increase in bearing life and reliability. However, there are several issues that need to be addressed if ELID grinding technology is to be integrated into the existing production process in the most effective way. These include:

Optimisation of the ELID grinding/lap-polishing process to achieve the required surface finish and profile accuracy in the minimum time.

•

• •

In-process monitoring and control of the ELID process. The integration of ELID grinding into the existing process chain.

Status: 36 month project. Started Oct 03 Publications of this work:

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GB22 High Efficiency Precision Grinding of Hard Materials

Contact Information: Professor David Stephenson School of Industrial & Manufacturing Science Cranfield University Cranfield, MK43 0AL UK Tel: +44 (0)1234 754751 Fax: +44 (0)1234 751172 Email: [email protected] http://www.cranfield.ac.uk/sims/mem/dave_s/dave_home.htm Abstract: The research has resulted in the best ever reported surface finish (2.3nm Ra compared to 30nm Ra) on directly ground hard steels and bimetallics produced at stock removal rates typically one order of magnitude higher than previously published. The need to use ultra-fine abrasive grits (typically <1 um) and small depth of cut (at the micron or sub-micron level) to achieve nanometre surface finish has been shown to be unnecessary if a dynamically stiff machine tool is used. The current work has used 75 um CBN grits and depths of cut up to 500um. The development of optical quality surfaces can be considered in terms of the processes occurring in the primary and secondary finishing zones of the cup-wheel, with the final surface finish enhanced by the burnishing action of worn CBN grits within the finishing zone. Surface finish is limited by the pull-out of carbides in the secondary finishing zone. This limitation can be overcome by using electrolytic in-process dressing (ELID), which maintains CBN grit protrusion and sharpness. This promotes cutting of the carbides at the ground surface and ensures a high level of surface integrity although the burnishing action of grits is reduced resulting in a slightly higher roughness for the metal matrix. The research has demonstrated that optical quality surfaces (<10nm Ra) can be directly ground on hard metallics. This is of great significance to many manufacturing processes where lapping and polishing procedures are used to obtain the final surface characteristics. The elimination of these finishing steps by direct grinding will have a major impact on time and cost to manufacture and indirectly provide important environmental and social benefits. Status: Completed 2002 Publications of this work: 1. D J Stephenson, J Hedge and J Corbett, 'Surface finishing of Ni-Cr-B-Si composite coatings

by precision grinding', Int. J. of Machine Tools and Man., 42, 2002, pp 357-363. 2. D J Stephenson, D Veselovac, S Manley and J Corbett, 'Ultra-precision grinding of hard

steels', Precision Engineering: Journal of the International Societies for Precision Engineering and Nanotechnology, 25,(2001), 336-345.

3. D J Stephenson, J Corbett, and J Hedge, 'Ultra Precision Grinding Using the Tetraform Concept', Abrasives Magazine, Feb/March Issue, 2002, pp 12-16.

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GB23 SATURN – Superabrasive TURNing an Integrated Approach to High Efficiency Grinding Process

Contact Information: Professor David Stephenson School of Industrial & Manufacturing Science Cranfield University Cranfield MK43 0AL UK Tel: +44 (0)1234 754751 Fax: +44 (0)1234 751172 Email: [email protected] http://www.cranfield.ac.uk/sims/mem/dave_s/dave_home.htm Abstract: The aim of the proposed research is to establish the thermal and physical threshold conditions for superabrasive turning within the high efficiency deep grinding (HEDG) regime and hence develop a strategy to achieve damage free grinding for cylindrical workpieces. The principal objectives of the programme are:

• To develop and validate thermal models for HEDG when grinding cylindrical components. • To develop a method for temperature measurement during cylindrical grinding. • To investigate fluid delivery strategies for optimum cooling efficiency in cylindrical HEDG. • To develop burn threshold diagrams appropriate to cylindrical HEDG which can be used to

identify the process conditions necessary to achieve low grinding zone temperatures. • To develop a control strategy that can be used for continuous monitoring of cylindrical

HEDG to ensure optimum surface integrity together with the most cost effective processing conditions.

Status: Jan 03 – Dec 05 Publications of this work: 1. T Jin and D J Stephenson, 'Thermal analysis on the cylindrical grinding in HEDG mode', 5th

Int. Conf. on Behaviour of Materials in Machining, 11-14th November 2002, Chester, Institute of Materials, Minerals and Mining, pp 299-302

2. T Jin and D J Stephenson, ‘Investigation of the Heat Partitioning in High Efficiency Deep Grinding’, Int. J of Machine Tools and Manufacture, 43 (2003) pp. 1129-1134.

3. T Jin, D J Stephenson, ‘Three Dimensional Finite Element Simulation of Transient Heat Transfer in High Efficiency Deep Grinding’, Annals of the CIRP, Vol. 43/1, 2004.

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GB24 ULTRAFLEX - Development of Innovative Manufacturing Technologies for Reducing Process Chain

Contact Information: Professor David Stephenson School of Industrial & Manufacturing Science Cranfield University Cranfield MK43 0AL UK Tel: +44 (0)1234 754751 Fax: +44 (0)1234 751172 Email: [email protected] http://www.cranfield.ac.uk/sims/mem/dave_s/dave_home.htm Abstract: Main industrial and technical objective of the Project is the development of a new process chain concepts, components, systems equipment and cutting tools aimed at improving environmental consciousness of machining chain (high production rate) for mechanical components. The Research activity is structured in two phases:

• Development of advanced machining and hardening processes, more productive, environment-friendly, and with increased surface quality, respect to the state of the art.

• Technical and economical evaluation of the different developed processes on the same demonstrator, CVT shaft, and development of a new process chain for this component.

From an economical point of view the Project aims to reduce the manufacturing costs by reducing the number of manufacturing steps, the machine cost through an increase of stock removal rate, the energy cost by local heating (induction and laser hardening) and coolant cost by dry or MQL processes. With respect to the environment impact and working conditions, the objective of the Ultraflex Project was to reduce highly the energy consumption and pollution emission, using dry or MQL cutting processes and by changing from conventional carburising to in-line hardening processes (induction or laser hardening) and air quenching (no washing product required). This approach will reduce the health risks for workers, since about 30% of the job related skin diseases in this area are caused by contact with cutting fluids. Dry machining technologies will reduce the hazardous impact also during waste disposal. Status: 36 month project – completed June04 Publications of this work: 1. T Jin, D J Stephenson and J Corbett, 'Burn threshold of high carbon steel in High Efficiency

Deep Grinding', Proc I Mech E Vol. 216 Part B Journal of Engineering Manufacture, 2002, pp 357-364.

2. D J Stephenson, T Jin and J Corbett, 'High Efficiency Deep Grinding of a Low Alloy Steel with Plated CBN Wheels', Annals of the CIRP, 51/1, 2002, 241-244

3. T Jin and D J Stephenson, ‘Effects of grinding fluids in High Efficiency Deep Grinding’, Grinding and Abrasives Magazine, Aug/Sept, 2002, pp 4-6.

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GB25 Ultra Precision Surfaces: a New Paradigm - Accuracy Capability of 1 part in 108

Contact Information: Professor David Stephenson School of Industrial & Manufacturing Science Cranfield University Cranfield MK43 0AL UK Tel: +44 (0)1234 754751 Fax: +44 (0)1234 751172 Email: [email protected] http://www.cranfield.ac.uk/sims/mem/dave_s/dave_home.htm Abstract: We aim to produce ultra precision surfaces at ten times the accuracy and with ten times greater speed than the current state of the art. We also address the pent-up demand for producing “free form” surfaces and their enormous impact on future science and technology. This project is ambitious in establishing a step-change advance in the processing route for nanometrically smooth and precise complex shaped surfaces, produced by grinding or other ultra-precision process. System and process research will establish key enabling technologies. These will be combined in a novel way to demonstrate a deterministic manufacturing capability at relative levels of precision in the range of 1 part in 108. This represents ultra precision processing at an unrivalled level. The developed research equipment will be brought together at a single location to provide the UK with a unique capability for processing ultra precise complex form surfaces. The developed enabling technologies and systems will have a generic impact on the fabrication of optical systems enabling diverse research areas, such as next generation extra large telescope optics, EUV (and ultimately X ray) wafer stepper optics, metrologic interferometers, optics for future space missions, compact surveillance and defence systems. Status: Started May 04 Publications of this work: None yet

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GB26 An Integrated FEA Approach to the Design and Analysis of Grinding Machines Contact Information: Professor Kai Cheng Director, Advanced Manufacturing Technology Research Group (AMTRG) Faculty of Information and Engineering Systems Leeds Metropolitan University Calverley Street, Leeds LS1 3HE UK Tel: 44-113-283 6731 Fax: 44-113-283 3110 email: [email protected]://care.ies.lmu.ac.uk/ Abstract: The purpose of this project is to investigate and develop a novel integrated machine tool and process machining strategy that would minimize component form and surface finish errors and yet maximize material removal rates throughout the entire working volume. This methodology has been applied to two medium/large, ultra precision/precision, grinding/milling machines under review for comparison purposes. In order to achieve the targets for this program for larger machines there is a need to research into machine structural elements (including foundations) and their respective machining processes. Improvement of the machining accuracy and productivity will necessitate investigation into the mechanics of the machining process, a variety of materials, and the diverse application of the process modelling for the machine types and configurations. Machine performance will see the need for developing measurement practices, error identification and correction for errors in the process and a determination of the dependency of foundations (concrete or otherwise) for the range of machine tools and a determination of a method as to how the various parameters can be optimized. The modelling and simulation results will be fed into the design, build and assembly of the next generation of machines to be used in the predictive control of the machining process. Key Issues of the Work: • Integrated FEA codes for modelling and simulation of the machine and process dynamics

simultaneously • Design guidelines and tools for precision grinding machines Publication of this Work: 1. P.Y. Pan, K. Cheng and D.K. Harrison, Using fuzzy logic in processing design specifications

and its computerized implementation, Proceedings of the 16th International Conference on Computer Aided Production Engineering, Edinburgh, UK, 7-9 August 2000, IMechE Professional Engineering Publishing Ltd, pp.465-474.

2. D. Huo, K. Cheng, D. Webb and F. Wardle, A novel FEA model for the integral analysis of a machine tool and machining processes, Key Engineering Materials, Vol.257, 2004, pp.45-50.

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GB27 A Multimedia Based Intelligent Design Tool for Aerostatic Bearings Contact Information: Professor Kai Cheng Director, Advanced Manufacturing Technology Research Group (AMTRG) Faculty of Information and Engineering Systems Leeds Metropolitan University Calverley Street, Leeds LS1 3HE UK Tel: 44-113-283 6731 Fax: 44-113-283 3110 email: [email protected]://care.ies.lmu.ac.uk/ Abstract: The purpose of this project is to develop a multimedia based intelligent tool for the design of aerostatic bearings. The tool aims to be a general design aid for aerostatic bearings including those used in grinding machines and lapping machines. The tool is computational powerful, user-friendly and highly interactive. Key Issues of the Work: • Modelling and simulation of aerostatic journal bearings • Realistic simulation (3D) of aerostatic spindle performances • Design and training tools Publications of this Work: 1. J. Toussaint and K. Cheng, A generic web-based tooling selection system for e-

manufacturing, Proceedings of the International Manufacturing Conference (IMC-19), 28-30 August 2002, Belfast, UK (CD-ROM).

2. M.L. Yang, K. Cheng and G.E. Taylor, Implementing Internet-based Agile Virtual Manufacturing Enterprises (iAVMEs) with Java and Linux technologies, Proceedings of the International Conference on e-Engineering: A Challenge for Global Manufacturing in the 21st Century, 16-18 September, 2001, Xi'an, China.

3. J. Toussaint and K. Cheng, Web-based 3D modelling for agile design and manufacturing: theory and application perspectives, Proceedings of the 1st CIRP (UK) Seminar on Digital Enterprise Technology (DET02), 16-17 September 2002, Durham, UK (CD-ROM).

4. R. Bateman and K. Cheng, Web-based distributed manufacturing and mass customization, Proceedings of the 1st CIRP (UK) Seminar on Digital Enterprise Technology (DET02), 16-17 September 2002, Durham, UK (CD-ROM)

5. R. Holt, K. Cheng and D. Webb, Design of a test rig for aerostatic bearings, Proceedings of the 19th National Conference on Manufacturing Research (NCMR), Glasgow, UK, 9-11 September 2003, pp.323-328.

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GB28 Abrasive Nanometric Machining: Modelling, Simulation and Application Promises Contact Information: Professor Kai Cheng Director, Advanced Manufacturing Technology Research Group (AMTRG) Faculty of Information and Engineering Systems Leeds Metropolitan University Calverley Street, Leeds LS1 3HE UK Tel: 44-113-283 6731 Fax: 44-113-283 3110 email: [email protected]://care.ies.lmu.ac.uk/ Abstract: This research proposes a novel approach to investigate the fundamental aspects of the abrasive nanometric machining process. The approach, by taking account of the dynamic cutting force, chatters, system structural dynamics, surface topography and surface integrity, models the surface generation in the complex abrasive machining process at the nanometric scale. The investigation takes nanogrinding of hard steels as a case study. The simulation results are consistent with the nanogrinding trial results. The potential and application of abrasive nanometric machining are further explored to a variety of engineering materials for electronic, automotive and optical manufacturing industries. Key Issues of the Work: • MD (molecular dynamics) based modelling and simulation • Surface generation and surface integrity modelling (surface roughness, micro-hardness,

microstructure, residual stress and fatigue) • Micro/nano grinding and abrasive machining applications Publications of this Work: 1. S. Yu, B. Lin, Q. Guan and K. Cheng, An experimental study on molecular dynamics

simulation in nano-metric grinding, Proceedings of the 16th International Conference on Computer Aided Production Engineering, Edinburgh, UK, 7-9 August 2000, IMechE Professional Engineering Publishing Ltd, pp.155-162

2. K. Cheng, X. Luo and D. Webb, A novel systematic approach to modelling precision machined surfaces based on mathematical transforms, Proceedings of the 5th International Conference on Laser Metrology, Machine Tool, CMM and Robot Performance (LAMDAMAP 2001), Birmingham, UK, 4-6 July 2001, WIT Press, pp.183-190.

3. K. Cheng, X. Luo, R. Ward and X. Liu, Modelling and control of the surface integrity and functionality in precision machining, Proceedings of the 3rd Euspen International Conference, 27-30 May 2002, Eindhoven, The Netherlands, Vol. 1, pp.221-224.

4. X. C. Luo and K. Cheng, Abrasive nano-metric machining: modelling, simulation and its application promise, Key Engineering Materials, Vol.258, 2004, pp.27-32.

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GB29 Intelligent and Adaptive Control for Grinding Contact Information: Dr Michael Morgan Manager, Advanced Manufacturing Technology Research Laboratory (AMTReL) General Engineering Research Institute (GERI) Liverpool John Moores University Byrom Street Liverpool, Merseyside L3 3AF, UK. Tel: +44 151 231 2590 / 2126 Email: [email protected] Abstract: A generic intelligent control system was designed to control a range of grinding processes using a group of adaptive control strategies. The aims of the intelligent system were to achieve size, roughness and shape tolerances within a minimum average cycle time. The system, based on a pc platform, had the capability of being integrated into a range of CNC machine tools. Adaptive features / strategies developed for achievement of maximum production rate included: adaptive feedrate; adaptive workspeed; adaptive dwell; adaptive target position with and without gauging; adaptive wheel wear compensation with and without gauging. A robust and reliable technique was developed for the identification of the system time constant based on power integration. The adaptive features referenced the thermal model to ensure a damage criterion was not breached. A series of control routines were designed for implementation of the adaptive features.

Key Outcomes of the Work: • Strategies developed for adaptive control routines • Algorithms developed for time constant identification • Control routines designed for adaptive control implementation • Generic intelligent control system framework established

Status: Ongoing Publications of this work: 1. D R Allanson, W B Rowe, X Chen, A Boyle, “Automatic Dwell Control in Computer

Numerical Control Plunge Grinding” Proc I Mech E, 1997, v211, Part B, 565-575. 2. W B Rowe, C Statham, J Liverton, J Moruzzi, 'Advances in the Application of New Control

System Architecture for Precision Machine Tools', ASI 98, 1998, Bremen Univ.,186-193. 3. W B Rowe, C Statham, J Liverton, J Moruzzi, “ An Open CNC Interface for Grinding

Machines”, Int Journal of Manufacturing Science & Technology. 1999, 1, 1, 17-23. ISSN 1524-1548. (Advanced Manufactuing Solutions Co Ltd, USA)

4. W B Rowe, Y Chen, et al., “ Strategies for a Generic Intelligent Control System for Grinding - Part 1: Development”, Int. J. for Manuf. Science and Prod., 1999, 2, 2, 69-78.

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5. W B Rowe, Y Chen, J L Moruzzi, B Mills, “ Strategies for a Generic Intelligent Control System for Grinding - Part 2: Internal CBN Grinding”, The International Journal for Manufacturing Science and Production 1999, 2, 2, 79-89.

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GB30 Fluid Application in Grinding Contact Information: Dr Michael Morgan Manager, Advanced Manufacturing Technology Research Laboratory (AMTReL) General Engineering Research Institute (GERI) Liverpool John Moores University Byrom Street Liverpool, Merseyside L3 3AF, UK. Tel: +44 151 231 2590 / 2126 Email: [email protected] Abstract: Grinding fluid plays a vital role in achieving high removal rates and good workpiece quality. There are however, conflicting recommendations for design of fluid application systems and a lack of knowledge concerning principles of fluid delivery into the grinding contact. In consequence, fluid burn-out is common, grinding quality suffers and substantial energy is wasted in larger production grinding systems. Previous research in the laboratory has identified that the achievement of ‘useful’ flow is critical for effective fluid performance. A model has been developed that correlates spindle power for fluid acceleration, wheel speed and delivery-nozzle jet velocity with ‘useful’ flow. The model benefits from simplicity and wide applicability and has been validated with experiment results. This important finding has provide the basis for current research that aims to further quantify the effects of wheel porosity, wheel speed, jet velocity and nozzle flowrate on ‘useful’ flow. ‘Useful’ flow will be related to grinding performance including models of workpiece quality and material removal rate. A User Guidance Manual will be developed to guide industry on the design of optimised fluid delivery systems

Key Outcomes of the Work: • Development of a widely applicable model for fluid systems design • Pressure and velocity mapping (from Laser Doppler Anemometry techniques) of fluid flows

in the boundary layer and entry region • Nozzle design methodologies • A workable tool for industry to achieve a total optimised fluid application system

Status: Ongoing Publications of this work: 1. S Ebbrell, N H Woolley, Y D Tridimas, et al., “The Effects of Cutting Fluid Application

Methods on the Grinding Process”, Int. J. Mach. Tools and Manuf., 2000, 40, 209-203. 2. V K Gviniashvili, M N Morgan, N H Woolley, W B Rowe, “Useful Flowrate in Grinding”

Int. J Machine Tools and Manufacture, 2003,

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3. V Gviniashvili, W B Rowe, M N Morgan, N H Woolley, “Modelling of Useful Flowrate in Grinding Based on Spindle Power”, Int. Symposium on Advanced Abrasive Technology November 2003, Bristol. Key Engineering Materials, v257-258, (2004) pp 333-338.

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GB31 Grinding Contact Mechanics Contact Information: Dr Michael Morgan Manager, Advanced Manufacturing Technology Research Laboratory (AMTReL) General Engineering Research Institute (GERI) Liverpool John Moores University Byrom Street Liverpool, Merseyside L3 3AF, UK. Tel: +44 151 231 2590 / 2126 Email: [email protected] Abstract: Estimates of the size of the contact region for abrasive machining processes had previously varied by up to 600 per cent. The contact length is of considerable tribological importance since contact length governs :

• the length of the sliding contact • the intensity of the heat input • the thickness of the uncut chips • the kinematic roughness of the workpiece • the time of contact and number of grains in contact • abrasive wear

This work has established experimental validated models of the grinding contact length. The models accommodate elastic deflections of both the wheel and workpiece, and the effect of roughness between contacting surfaces. The work has also established the effect of fluid on contact length.

Key Outcomes of the Work: • Development of analytical models for grinding contact length. • Determination of effects of rough surfaces and contact deflections on contact length. • Development of techniques for measurement of grinding contact length

Status: Ongoing Publications of this work: 1. H S Qi, W B Rowe, B Mills “ Contact Length in Grinding, Part 1.Measurement” Proc

IMechE J Engineering Tribology, 1997, 211, Part J, 67-76. 2. H S Qi, W B Rowe, B Mills “ Contact Length in Grinding, Part 2.Evaluation”Proc IMechE J

Engineering Tribology, 1997, 211, Part J, 77-85. 3. W B Rowe, H S Qi, “Contact Behaviour in Grinding”, Int. Manufacturing Engineering

Conference 7-9 Aug 1996, 543-545. ISBN 965 294 121 2.

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4. H S Qi, W B Rowe, B Mills, “Experimental Investigation of Contact Behaviour in Grinding” Tribology International. 1997, 30, 4, 283-294. 0301-679X/97.

5. H S Qi, W B Rowe, B Mills, E O Ezugwu, ‘Fuzzy Contact Phenomena in Manufacturing Tribology’, the 4th Int Conf on Progress in Cutting and Grinding, 5-9th October 1998, Urumqi and Turpan, China organised by Beijing University, Chinese Society of Metal-cutting and Japan Society of Precision Engineering.

6. H S Qi, W B Rowe, B Mills, “Fuzzy Contact and Its Effect on Thermal Processes” Key Engineering Materials, 2001, 202-203, 15-24. (Trans Tech Publications, Switzerland).

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GB32 Grinding Wheel Characterisation / Performance Contact Information: Dr Michael Morgan Manager, Advanced Manufacturing Technology Research Laboratory (AMTReL) General Engineering Research Institute (GERI) Liverpool John Moores University Byrom Street Liverpool, Merseyside L3 3AF, UK. Tel: +44 151 231 2590 / 2126 Email: [email protected] Abstract: Wheel structure has a critical influence on grinding performance. The more descriptive the parameters of the grinding wheel, the more accurately grinding performance can be predicted. This work investigated methods and techniques to measure wheel topography. Parameters to fully describe wheel structural properties were also established. Surface replication techniques were developed and the relationship between wheel structural parameters and grinding performance were determined.

Further aspects of the work investigated the performance characteristics of vitrified cBN with particular reference to the effects of high wheel speed. Increased wheel speed has widely been seen as a means to increased productivity. However, increased wheel speeds have implications on machine tool design in particular excitation frequencies and spindle design. The work established that increased wheel speed is the most important factor in achievement of improved quality and wheel life. The results clearly supported a move toward high speed grinding machines.

Key Outcomes of the Work: • Establishment of descriptive parameters for wheel structural properties • Development of wheel surface replication techniques • Identification of importance of high wheel speed • Generation of direct charts to describe effects of grinding parameters on grinding

performance

Status: Ongoing Publications of this work: 1. R Cai, W B Rowe, M N Morgan, “Structural Properties of Vitrified CBN Grinding Wheels”

Advances in Manufacturing Technology, September 2002, pp349-353. (Ed. K Cheng and D Webb), Professional Engineering Publishing Ltd, (IMechE, London) ISBN 1 86058 378 4.

2. R Cai, W B Rowe, M N Morgan, “The Effect of Porosity on the Grinding Performance of Vitrified CBN Wheels”, Int. Symposium on Advanced Abrasive Technology, Hong Kong,

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November 2002. Japan Soc. For Abr. Tech. Advances in Abrasive Technology V(Eds:Y Gao, J Tamaki, K Kitajima) pp 295-300. Trans Tech Publications Ltd, Switz, Germany, UK and USA, ISBN 0-87849-910-5 Also in Key Engineering Materials, v238-9,(2003)pp295-300.

3. Cai, R., Rowe, W. B., Morgan, M.N., 2002, ‘Measurement of Vitrified CBN Grinding Wheel Topography’, ISAAT 2002, Hong Kong. Japan Soc. For Abr. Tech. Advances in Abrasive Technology V, (Ed. Y Gao, J Tamaki, H Kitajima) pp 301-306. Trans Tech Publications Ltd, Switz, Germany, UK and USA, ISBN 0 87849 910 5. Also in Key Engineering Materials v238-9, (2003) pp 301-306.

4. S Ebbrell, W B Rowe, M N Morgan, “Process Characterisation in Grinding AISI 52100 with Vitrified CBN”, Int. Symposium on Advanced Abrasive Technology, Hong Kong, November 2002. Japan Soc. For Abr. Tech. Advances in Abrasive Technology V(Eds:Y Gao, J Tamaki, K Kitajima) pp 333-337. Trans Tech Publications Ltd, Switz, Germany, UK and USA, ISBN 0-87849-910-5 Also in Key Engineering Materials, v238-9,(2003)pp333-337.

5. R Cai, W B Rowe, M N Morgan, “Grinding Performance of High-Porosity Fine-Grain Vitrified CBN Wheels for Inconel 718” Int J Manufacturing Science and Technology, 2003, 5, nos 1-2, 5-9. Freund Publishing, Israel. ISSN 0793 6648.

6. M N Morgan, W B Rowe, S E Ebbrell, 2004, ‘Process Requirements for Reduced-Cost Precision Grinding’, , Advances in Manufacturing Technology XX (Ed. S Saad, T Perera) Sep 2004, pp 12-18, ISBN 1 84387-088-6.

7. W B Rowe, M N Morgan, , S E Ebbrell, 2004, ‘Process Requirements for Cost-Effective Precision Grinding’, Annals of the CIRP, v 53/1.

8. Cai, R., Rowe, W. B., 2004,’Assessement of vitrified cBN Wheels for Precision Grinding’, Int. J.of Machine Tools and Manufacture, v44, pp1391-1402. ISSN 0890-6955.

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GB33 Grinding Wheel Dressing and Simulation Contact Information: Dr Michael Morgan Manager, Advanced Manufacturing Technology Research Laboratory (AMTReL) General Engineering Research Institute (GERI) Liverpool John Moores University Byrom Street Liverpool, Merseyside L3 3AF, UK. Tel: +44 151 231 2590 / 2126 Email: [email protected] Abstract: The behaviour of the grinding wheel during the grinding process is strongly dependent on the topography of the grinding wheel surface. The surface topography of the grinding wheel is generated by the dressing process and subsequently modified by the grinding process. Research work has established that the effect of the dressing condition on grinding behaviour is very strong particularly at the initial grinding stage and it was found that the best condition of the grinding wheel is achieved when the variation in grinding power after dressing is a minimum. Strategies to optimise the dressing process were developed based on this finding. Simulation techniques were also developed to test feed cycles and to evaluate control strategies. The topography of the wheel cutting surface was modelled for the single diamond dressing process on a simulated grinding wheel. The simulated cutting surface was also used for further simulations of grinding. By matching simulated and experimental results it was possible to explain the relative importance of dressing and grinding parameters.

Key Outcomes of the Work: • Dressing strategy for optimising and stabilising grinding performance • Simulation of dressing process and subsequent grinding process for evaluation of grinding

performance

Status: Ongoing Publications of this work: 1. X Chen, D R Allanson, W B Rowe, “Life Cycle Model of the Grinding Process” 1996

Proceedings of Advanced Summer Institute - ASI 96, ICIMS Network of Excellence, 2-6 June 1996, Toulouse, 45-52.

2. X Chen, W B Rowe, B Mills, D R Allanson, “Analysis and Simulation of the Grinding Process, Part IV, Effects of Wheel Wear” Proc of Int J Machine Tools and Manufacture, 1997, 38,1-2, 41-49. 0890-6955/98

3. X Chen, D R Allanson, W B Rowe, “Life Cycle Model of the Grinding Process”, Computers in Industry, 1998, 36, 5-11.

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4. W B Rowe, Y Chen, J L Moruzzi, B Mills, “ Strategies for a Generic Intelligent Control System for Grinding - Part 2: Internal CBN Grinding”, The International Journal for Manufacturing Science and Production 1999, 2, 2, 79-89.

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GB34 High Efficiency Deep Grinding (HEDG) Contact Information: Dr Michael Morgan Manager, Advanced Manufacturing Technology Research Laboratory (AMTReL) General Engineering Research Institute (GERI) Liverpool John Moores University Byrom Street Liverpool, Merseyside L3 3AF, UK. Tel: +44 151 231 2590 / 2126 Email: [email protected] Abstract: Regimes of deep grinding range from creep grinding conducted at low workspeeds to high efficiency deep grinding (HEDG) at faster workspeeds. HEDG is characterised by extremely high material removal rates and low specific grinding energy and has potential to compete as a primary material removal process. At intermediate depths of cut, grinding is likely to be impossible due to high temperatures and damage to the workpiece and wheel. Analytical techniques have been developed to describe the heat transfer mechanisms and to quantify the physical processes involved in achievement of HEDG. The thermal analysis has taken into account developments in thermal modelling of shallow cut processes. Important differences between HEDG and shallow cut processes have been distinguished. The effects of process conditions on workpiece quality, operational efficiency and removal rates have been determined. The importance of effective fluid delivery and fluid convection effects have been identified.

Key Outcomes of the Work: • Analytical model of heat transfer in HEDG developed and validated with experimental

results • Fluid convection values proposed • Requirements for achievement of HEDG established • Dedicated HEDG machine tool developed

Status: Ongoing Publications of this work: 1. W B Rowe, “Temperature Case Studies in Grinding Including an Inclined Heat Source

Model” Proc. IMechE, Part B, Journal of Engineering Manufacture, 2001, 215, Part B, 473-491. ISSN 0954-4054.

2. W B Rowe. “Thermal Analysis of High Efficiency Deep Grinding”, International J. of Machine Tools and Manufacture, 2001, 41, 1-19. ISSN 0890-6955.

3. W B Rowe,T Jin, “Temperatures in High Efficiency Deep Grinding (HEDG)”, Annals of the CIRP, vol. 50/1, 2001 pp205 –208. ISBN 3-905 277-35-2.

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4. T Jin, W B Rowe, D McCormack, “Heat Penetration in Deep Grinding Including a Transient Analysis” Proc Nat. Conf. On Manufacturing Research, Sep 2001, Cardiff University and Proc I MechE.

5. T Jin, W B Rowe, D McCormack, “Temperatures in Deep Grinding of Finite Workpieces” International J. of Machine Tools and Manufacture, 2002, 42, 1, 53-59. ISSN 0890 – 6955.

6. T Jin, D J Stephenson, W B Rowe, “Estimation of the Convection Heat Transfer Coefficient of Coolant within the Grinding Zone” Proc I Mech E, 2003, v217 Part B: J. of Engineering Manufacture, 397-407.

7. M N Morgan, W B Rowe, A Batako, “Energy Limitations in HEDG and Conventional Grinding” Int. Symposium on Advanced Abrasive Technology November 2003, Bristol Key Engineering Materials, v238-9,(2003) pp301-306. Key Engineering Materials, v239-40,(2004) pp.

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GB35 Control of Surface Integrity in Grinding Contact Information: Dr Michael Morgan Manager, Advanced Manufacturing Technology Research Laboratory (AMTReL) General Engineering Research Institute (GERI) Liverpool John Moores University Byrom Street Liverpool, Merseyside L3 3AF, UK. Tel: +44 151 231 2590 / 2126 Email: [email protected] Abstract: Low residual stress after grinding is an important requirement for surface integrity of stress sensitive components. If tensile residual stresses remain in the surface, the subsequent service life may be reduced under stress corrosion or fatigue conditions. The origins of residual stress in ground surfaces were studied to investigate whether a transitional temperature exists between compressive and tensile residual stresses. The most important factor for the determination of tensile residual stress is thermal expansion and contraction. A method to characterise the onset temperature for tensile residual stress was established. An analytical model was developed to predict the transitional temperature that was found to be strongly affected by the material properties, in particular the yield stress. Analysis has shown that prevention of tensile residual stresses can be a matter of prediction of the transition temperature and process control.

Key Outcomes of the Work: • Development of an analytical model for prediction of residual stress transition temperature. • Identification of critical temperatures for a range of steels.

Status: Ongoing Publications of this work: 1. X Chen, W B Rowe, D F McCormack, “Predicting Onset of Tensile Residual Stress in

Grinding”, Proceedings of the Society of Manufacturing Engineers Paper MR99-261. 3rd International Machining & Grinding Conference, Cincinnati, Oct, 1999.

2. X Chen, W B Rowe, D F McCormack, “Analysis of Transitional Temperatures for Tensile Residual Stress in Grinding”, Proceedings of 15th International Conference on Computer Aided Production Engineering, April 1999. Journal of Materials Processing,

3. X Chen, W B Rowe, “ Modelling Surface Roughness Improvement in Grinding”, Proceedings of the Institution of Mechanical Engineers, 1999, 213 Part B, 93-96. SC0198.

4. X Chen, W B Rowe, “Predicting the Transitional Boundary of Tensile Residual Stress in Grinding” Abrasives Magazine, 2000, Feb/March, 28-37.

5. X Chen, W B Rowe, D F McCormack, “Analysis of the Transitional Temperatures for Tensile Residual Stress in Grinding”, J Materials Processing Technology,(Elsevier), 2000, 107, 216-221. ISSN 0924-0136.

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6. D F McCormack, W B Rowe, T Jin, “Controlling the Surface Integrity of Ground Components”, Proceedings of the Society of Manufacturing Engineers 4th Internat. Machining and Grinding Conference, 7th-10th May 2001, Detroit. SME Paper MR01-236

7. W B Rowe, T Jin, D F McCormack, “Design of Abrasive Machining Processes” IMechE Proceedings. Quality, Cost and Efficiency in Manufacturing Processes, 21st March 2002, Broadway House, Westminster, London. Also Chapter 13 in Total Tribology – Towards an Integrated Approach, 2002, pp165-183. (Eds. I Sherrington, W B Rowe, R J K Wood), Professional Engineering Publishing Limited, London and Bury St Edmunds.

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GB36 Thermal Analysis of Grinding Contact Information: Dr Michael Morgan Manager, Advanced Manufacturing Technology Research Laboratory (AMTReL) General Engineering Research Institute (GERI) Liverpool John Moores University Byrom Street Liverpool, Merseyside L3 3AF, UK. Tel: +44 151 231 2590 / 2126 Email: [email protected] Abstract: Well-designed grinding processes usually enhance workpiece surface quality, producing low roughness, compressive or neutral residual stresses, and improved fatigue life. Conversely, poorly designed processes can lead to abusive grinding and a range of forms of surface / sub-surface damage. For critical components and parts of high added value it is therefore desirable to reduce grinding temperatures to minimize the risk of the occurrence of thermal damage. Temperature models have been developed for industrial application to assist the operator avoid conditions of high risk. The thermal analyses have greatly clarified the importance of the various physical processes involved in abrasive machining leading to radical developments such as creep grinding and high-efficiency deep grinding (HEDG). The analytical models can be validated by temperature measurements undertaken in the research laboratory. Thermocouple techniques have been developed for direct surface temperature measurement. Further work is continuing on the development of novel fibre-optic based techniques for temperature measurement.

Key Outcomes of the Work: • Development of thermal models for range of grinding processes • Development of techniques for direct surface and sub-surface temperature measurement. • Development of strategies for avoidance of thermal damage • Development of new regime grinding process (HEDG)

Status: Ongoing Publications of this work: 1. S C E Black, W B Rowe, B Mills and H S Qi “Experimental Energy Partitioning in

Grinding”, Proc Eurometalworking 94, 28 - 30 September 1994 held at University of Udine, Italy.

2. S Black, W B Rowe, H S Qi and B Mills “Temperature Measurements in Grinding” Proc 31st MATADOR Conference held at UMIST 20-21 April 1995, 409-413. Macmillan Press ISBN 0-333-64086-1.

3. W B Rowe,S C Black, M N Morgan and B Mills “Experimental Investigation of Temperature in Grinding” Annals of CIRP, 1995, 44, 1, 329-332. ISBN 3-905-277-23-9.

4. W B Rowe, S Black and B Mills “Temperatures in CBN Grinding”, Industrial Diamond Review, 1995, 4, 165-169.

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5. W B Rowe, S C Black, B Mills, H S Qi and M N Morgan “Analysis of Grinding Temperatures by Energy Partitioning” Proc IMechE Part B, J Engineering Manufacture, 1996, 210, 579-588. ISSN

6. W B Rowe, S C E Black and B Mills “Temperature Control in CBN Grinding” Int J of Advanced Manufacturing Technology, 1996, 12, 387-392.(SpringerVerlag)

7. W B Rowe, M N Morgan, S C E Black, B Mills “A Simplified Approach to Thermal Damage in Grinding” Annals of the CIRP, 1996, 45, 1, 299-302. ISBN 3-905277-25-5.

8. W B Rowe, S Black, B Mills, M N Morgan, H S Qi, “Grinding Temperatures and Energy Partitioning” Proc Royal Society, A, 1997, 453, 1083-1104.

9. M N Morgan, Z X Lin, W B Rowe, “Temperatures in Angle Approach Form Grinding” Int Seminar on Improving Machine Tool Performance, Fundacion Tekniker, San Sebastien, 6-8 July 1998.

10. W B Rowe, M N Morgan S C E Black, D R Allanson, 'Validation of Thermal Properties in Grinding” Annals of CIRP, 1998, 47,1, 275-279

11. M N Morgan, W B Rowe, S C E Black, D R Allanson, “Effective Thermal Properties of Grinding Wheels and Grains” Proceedings of the Institution of Mechanical Engineers, 1998, 212 Part B, 661-669.

12. M N Morgan, W B Rowe, “An Investigation of Temperatures in Form Grinding”, Proc 33rd Int MATADOR conf., 13-14 July 2000, UMIST.

13. M N Morgan,W B Rowe, “Design Procedure for Parameter Selection in Angle-approach Grinding” Advances in Manufacturing Technology XVI, September 2002, pp423-427. (Ed K Cheng and D Webb), Professional Engineering Publishing Ltd, (IMechE, London, UK). ISBN 1 86058 378 4.

14. W B Rowe, M N Morgan, A Batako, T Jin, 2003, “Energy and Temperature Analysis in Grinding” Keynote Paper, Sixth Int. Conf. And Exhibition on Laser Metrology, Machine Tool CMM and Robot Performance – LAMDAMAP, 1-4th July, 2003. Huddersfield University. Published in Laser Metrology and Machine Performance VI (Ed D G Ford), Pages 3-23, 2003. WIT Press, Southampton, UK. ISBN 1-85312-990-9.

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GERMANY

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G1 New Dressing Methods for Superabrasive Grinding Wheels Contact Information: Professor Dr.-Ing. Eckart Uhlmann Institute for Machine Tools and Factory Management Berlin University of Technology Berlin, Germany Email: [email protected] http: www.iwf.tu-berlin.de Responsible Research Engineer: Dipl.-Ing. Mathias Kirchgatter Email: [email protected] Abstract: For diamond grinding tools new methods including ultrasonic assisted dressing with rotating dressing tools are developed and tested. The studies contain continuous dressing, continuous sharpening and new conclusions about the development of the topography of the grinding tool. Key Issues of the Work: • Dressing of superabrasive grinding wheels • Application of continuous dressing (CD) and continuous sharpening (CS) Status: recently finished Publications of this work: Presently there are no publications available due to arrangements of confidentiality with collaborating industrial partners.

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http://dict.tu-chemnitz.de/dings.cgi?o=3001;count=50;service=en-de;query=responsible

G2 Cooling Lubricants in Grinding Contact Information: Professor Dr.-Ing. Eckart Uhlmann Institute for Machine Tools and Factory Management Berlin University of Technology Berlin, Germany Email: [email protected] http: www.iwf.tu-berlin.de Responsible Research Engineer: Dipl.-Ing. Hubert Szulczynski Email: [email protected] Abstract: Cooling lubrication has a significant influence on the process and the work results during grinding. A rising demand for surface quality and geometrical accuracy especially in machining new materials as well as an increasing environmental awareness lead to a demand for appropriate cooling lubricants or a way to omit them altogether. Depending on the used coolant the mechanical and thermal stresses lead to different friction as well as cutting and tool wear mechanisms. Key Issues of the Work: • Comparison of different cooling lubricants and additives for grinding of advanced ceramics • Technological investigations in viscosity, friction and wear Status: recently finished Publications of this work: 1. Spur, G.; Uhlmann, E.; Laufer, J.; Szulczynski, H.: Effective Mechanisms of Cooling

Lubrication in Grinding Hard Metal. In: WGP-Annals, Production Engineering VII (2000) 2; pp. 53-57.

2. Brücher, Th.: Kühlschmierung beim Schleifen keramischer Werkstoffe. Dissertation TU Berlin, 1996 and Berichte aus dem Produktionstechnischen Zentrum Berlin, 1996.

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G3 Grinding of Nickel-base Alloys Contact Information: Professor Dr.-Ing. Eckart Uhlmann Institute for Machine Tools and Factory Management Berlin University of Technology Berlin, Germany Email: [email protected] http: www.iwf.tu-berlin.de Responsible Research Engineer: Dipl.-Ing. Hubert Szulczynski Email: [email protected] Abstract: Nickel-base alloys are the type of alloys most commonly used for high stress gas turbine parts. The machining of these high performance materials is extremely difficult due to their out-standing property profile and the high demands regarding components. A major problem is insufficient knowledge about the correlation between machining parameters and the mechanical and thermal loads of the workpiece. The aim is to determine the subsurface damage during machining, to find suitable machining strategies for minimizing damage and for an economic machining of turbine materials as well as to create reproducible component characteristics. Grinding is a process that allows an economically efficient manufacture of complex contours. Key Issues of the Work: • Technological investigations in material removal and wear mechanisms • Reduction of the sub-surface damage of the work-piece by improved machining parameters

and coolant supply Status: recently finished Publications of this work: Presently there are no publications available due to arrangements of confidentiality with collaborating industrial partners.

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G4 High Efficiency Belt Grinding Contact Information: Professor Dr.-Ing. Eckart Uhlmann Institute for Machine Tools and Factory Management Berlin University of Technology Berlin, Germany Email: [email protected] http: www.iwf.tu-berlin.de Responsible Research Engineer: Dipl.-Ing. Hubert Szulczynski Email: [email protected] Abstract: The need for a high surface quality of a workpiece can either be the immediate demand of its function or a demand of the subsequent processing. In order to rule out surface irregularities the hot rolled steel are belt-ground before they are cold rolled to their final proportions. For the grinding of these strips abrasive belt machining has been established as the ideal manufacturing process. During the first step of the project significant project parameters were identified. Based on these parameters a control-loop was designed, which is iteratively optimized during the process. Key Issues of the Work: • Identification of significant parameters for belt grinding of hot rolled steel • Development of a control system for high efficiency belt grinding Status: recently finished Publications of this work: Presently there are no publications available due to arrangements of confidentiality with collaborating industrial partners.

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G5 High Speed Grinding with CBN Contact Information: Professor Dr.-Ing. Eckart Uhlmann Institute for Machine Tools and Factory Management Berlin University of Technology Berlin, Germany Email: [email protected] http: www.iwf.tu-berlin.de Responsible Research Engineer: Dipl.-Ing. Hubert Szulczynski Email: [email protected] Abstract: For applications in machine tooling and manufacturing automotive and power generation components high performance materials such as nickel based alloys are used. Alternative metallic materials competing with cast materials are ODS alloys and intermetallic phases such as TiAl that are manufactured in powder metallurgy. The investigations showed that high cutting speeds should be used during grinding with CBN, as opposed to grinding with corundum. The most important set parameters during grinding with CBN are related material removal rate, cutting speed and grinding wheel specification. The cooling lubrication has also a very important influence on the working result and the achievable cutting speed. Key Issues of the Work: • Technological investigations of high speed grinding with CBN using different machining

parameters and grinding wheel specifications • Influence of the cooling lubrication Status: recently finished Publications of this work: Presently there are no publications available due to arrangements of confidentiality with collaborating industrial partners.

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G6 Simulation and Technology in Face Grinding with Planetary Kinematics Contact Information: Professor Dr.-Ing. Eckart Uhlmann Institute for Machine Tools and Factory Management Berlin University of Technology Berlin, Germany Email: [email protected] http: www.iwf.tu-berlin.de Responsible Assistant: Dipl.-Ing. Tom Hühns Email: [email protected] Abstract: Since lapping reveals disadvantages in economical and ecological terms, face grinding with planetary kinematics becomes more and more important in industrial applications. The Institute for Machine Tools and Factory Management, Berlin University of Technology, has developed a model to analyse the kinematic potentialities of double-wheel machines. Technological investigations attempt to develop process strategies regarding the process parameters and the work result. Key Issues of the Work: • Correlations between kinematical parameters and material removal mechanisms as well as

correlations between kinematical parameters and work result • Modelling and Simulation of the face grinding process with planetary kinematics Status: on-going Publications of this work: 1. Ardelt, Th.: On the Effect of Path Curves on Process and Wheel Wear in Grinding on

Lapping Machines. In: Proceedings „3rd International Machining and Grinding Conference“, October 4-7, 1999, Cincinnatti, Ohio, USA, pp. 307-321.

2. Ardelt, Th.: Einfluss der Relativbewegung auf den Prozess und das Arbeitsergebnis beim Planschleifen mit Planetenkinematik. Dissertation TU Berlin, 2000 and Berichte aus dem Produktionstechnischen Zentrum Berlin, 2001.

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G7 Simulation of Abrasive Machining Contact Information: Professor Dr.-Ing. Eckart Uhlmann Institute for Machine Tools and Factory Management Berlin University of Technology Berlin, Germany Email: [email protected] http: www.iwf.tu-berlin.de Responsible Research Engineer: Dipl.-Ing. Christoph Hübert Email: [email protected] Abstract: Since cutting with undefined edges is considered a complex manufacturing process a number of different models have been developed to improve the general understanding of these processes and to predict the working results. Recent research activities covered the kinematical simulation of face grinding with planetary kinematics as well as questions regarding chip thickness modelling in ultrasonic assisted grinding. Key Issues of the Work: • Kinematical simulation of face grinding with planetary kinematics • Chip thickness modelling in ultrasonic assisted grinding Status: on-going Publications of this work: 1. Ardelt, Th.: Einfluss der Relativbewegung auf den Prozess und das Arbeitsergebnis beim

Planschleifen mit Planetenkinematik. Dissertation TU Berlin, 2000 and Berichte aus dem Produktionstechnischen Zentrum Berlin, 2001.

2. Uhlmann, E.; Daus, N.-A.; Hühns, T.; Szulczynski, H.: Kinematical Simulation of Ultrasonic Assisted Grinding. Presentation: CIRP 2004 General Assembly, Scientific Committee “G”, Kracow, Poland, August 27th, 2004.

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G8 Testing Method for Grinding Wheels Contact Information: Professor Dr.-Ing. Eckart Uhlmann Institute for Machine Tools and Factory Management Berlin University of Technology Berlin, Germany Email: [email protected] http: www.iwf.tu-berlin.de Responsible Research Engineer: Dipl.-Ing. Mathias Kirchgatter Email: [email protected] Abstract: Existing standards for grinding wheels do not allow the exact prediction of the behavior of the tool in process. Therefore a special testing method for grinding wheels has been developed. The testing method allows the comparison between an existing and tested tool with good performance and a new unknown tool. After few hours the potential of the new tool can be estimated and the decision for further efforts in optimizing the process can be made. The method is based on correlations between the measured grinding forces, the tool wear and the work result. Key Issues of the Work: • Development of brief testing methods for grinding wheels • Correlations are based on the measurement of grinding forces, tool wear and work result Status: on-going Publications of this work: Presently there are no publications available due to arrangements of confidentiality with collaborating industrial partners.

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G9 Tool Geometry in Peel Grinding Contact Information: Professor Dr.-Ing. Eckart Uhlmann Institute for Machine Tools and Factory Management Berlin University of Technology Berlin, Germany Email: [email protected] http: www.iwf.tu-berlin.de Responsible Research Engineer: Dipl.-Ing. Mathias Kirchgatter Email: [email protected] Abstract: Peripheral longitudinal external cylindrical grinding operations such as the grinding of shafts are often done by a reciprocating grinding process. In order to reduce the number of passes and the primary processing time peel grinding is an alternative method which can provide high surface qualities at a high infeed. The geometry of the grinding wheel is an important parameter for the work result in peel grinding. The fundamental relation between the geometry of the tool and the work result was the main point of the research project. Key Issues of the Work: • Fundamental influence of tool geometry in peel grinding • Process optimization including dressing and lubricant supply Status: recently finished Publications of this work: Presently there are no publications available due to arrangements of confidentiality with collaborating industrial partners.

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G10 Ultrasonic Assisted Grinding Contact Information: Professor Dr.-Ing. Eckart Uhlmann Institute for Machine Tools and Factory Management Berlin University of Technology Berlin, Germany Email: [email protected] http: www.iwf.tu-berlin.de Responsible Research Engineer: Dipl.-Ing. Christoph Hübert Email: [email protected] Abstract: Ultrasonic assisted grinding is an innovative approach for the machining of advanced ceramics and other brittle material with high material removal rates and comparatively low process temperatures. Present research activities put a special focus upon modelling the complex material removal mechanisms due to the unique kinematics involved in the process. Key Issues of the Work: • Examination of material removal and wear mechanisms • Application of ultrasonic assisted grinding in machining of advanced ceramics, Status: on-going Publications of this work: 1. Uhlmann, E.; Daus, N.-A.: Grinding of Structural Ceramic - Status and Perspectives for

Industrial Applications. In: Proceedings of CIMTEC, 10th International Ceramics Congress & 3rd Forum on New Materials, Florence, Italy, 2002.

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G11 Opto-electronical Measuring System for the Surface Assessment of Grinding Tools Contact Information: Dipl.-Phys. Heinz-Wolfgang Lahmann Gesellschaft für Fertigungstechnik und Entwicklung e.V. Am Bad 2, 98574 Schmalkalden Germany Email: [email protected] Abstract: The main technical objective was the development of a contactless working measuring system in order to check objective and effective surface of galvanically bounded grinding tools. By means of this system essential prerequisites should be realised for the control of products in the manufacturing process. By means of a developed optical measuring system it is now possible to evaluate rough-structured surfaces with different properties of reflections. The topography is objectively assessed in an automated measuring- and evaluation process. Key Issues of the Work: • Contactless measurement of grinding tools • Topography of tools Status: Finished Publication of this work: 1. Barthelmä, F., Lahmann, H.-W., Stöckmann, M.: Qualitätsbewertung von galvanisch

gebundenen Schleifwerkzeugen mittels Bildverarbeitung. IDR Ausgabe 4/2003, S. 302

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G12 Development and optimisation of a grinding technology for cutting tools with small Dimensions

Contact Information: Dr.-Ing. Marlies Patz Gesellschaft für Fertigungstechnik und Entwicklung e. V. Am Bad 2, 98574 Schmalkalden, Germany Email: [email protected]: www.gfe-net.de Abstract: The aim of the work consisted in the development and optimisation of grinding technologies for production of powerful drilling and milling tools with small dimensions for different fields of application, for example die and mould making, watch industry or medicine technique. For this purpose different tool materials and grinding strategies were tested. Criteria of evaluation were the quality of the grinded cutting edges and tool forces and the behaviour of the cutting tools in practical tests.

Key Issues of the Work: Grinding of cutting tools with small dimensions Optimisation of grinding technology Status: Finished Publication of this work: Patz, M. ; Maul, T.: Optimierung der Leistungsfähigkeit von Fräswerkzeugen mit kleinen Abmessungen. In: Jahresbericht 1998 der Gesellschaft für Fertigungstechnik und Entwicklung e. V., Schmalkalden, S. 21

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G13 Investigations in Grinding Cutting Tools for Hard Machining Contact Information: Dr.-Ing. Marlies Patz Gesellschaft für Fertigungstechnik und Entwicklung e. V. Am Bad 2, 98574 Schmalkalden, Germany Email: [email protected]: www.gfe-net.de Abstract: Content of the work was the optimisation of the grinding technology and the process-relevant geometrical features of cutting tools for use in hard machining. The investigations were realised using CBN-materials of different producers. The materials showed in part great differences in grinding behaviour and during the cutting tests. Therefore adapted grinding strategies were necessary.

Key Issues of the Work: Grinding of CBN-Tools Optimisation of grinding technology Status: Finished Publication of this work: 1. Patz, M. ; Dittmar, H. ; Hess, A. ; Wagner, W.: Better hard turning with optimised tooling.

In: Industrial Diamond Review 60 (2000) 4, S. 277-282

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G14 Precision Contour Grinding of Optical Glasses Using Coarse-Grained Diamond Wheels

Contact Information: Dr. Qingliang Zhao LFM (Laboratory for Precision Machining) Badgasteiner Straße 2 D-28359 Bremen Germany Tel: +49-421-2189451 Fax: +49-421-2189441 Email: qlzhao@[email protected] [email protected]

Abstract: The objective of this research project is the ductile contour grinding of large optical surfaces with high surface and sub-surface integrity by using well-conditioned coarse-grained diamond wheels. The wear rate of coarse-grained wheels is much lower compared to fine-grained wheels, resulting in a more cost effective and competitive manufacturing process.

In realizing this, nickel electroplated diamond grinding wheels featuring grain sizes from 46μm to 151μm have been applied. We have developed an efficient and precise conditioning technique assisted by ELID (electrolytic in-process dressing) for flattening the diamond grains and creating an excellent roundness of the grinding wheel. An optical distance measuring system was used to measure the improvement of the wheel roundness.

Grinding experiments using well-conditioned coarse-grained diamond wheels were carried out on optical glasses BK7 and Zerodur. A piezoelectric dynamometer was used to monitor the grinding forces. Atomic force microscopy (AFM), white-light interferometry and scanning electron microscopy were used for characterizing the surface topography and sub-surface integrity of the ground glass samples as well as the wear mechanisms of the grinding wheels.

The experimental results show that the conditioned coarse-grained diamond wheels can be used for ductile contour grinding of optical glasses with high material removal rates yielding excellent surface finishes (Ra: 1.7nm, measured by AFM, 80μm scan). We will discuss the performance of the conditioned coarse-grained diamond wheels compared to fine-grained diamond wheels in terms of: surface topography and sub-surface damage of the ground specimens, process forces and wheel wear as a function of stock removal.

Key Issues of the Work: • Conditioning the coarse-grained diamond grinding wheels in obtaining requested run-out

error and top-flattened diamond grains. • Evaluating the grinding performance on optical glasses with these wheels. Status: Ongoing

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G15 Surface and Subsurface Integrity Mechanisms in Diamond Grinding of Optical Glasses on a High Close-Loop Stiffness Machine Tool

Contact Information: Dr. Qingliang Zhao LFM (Laboratory for Precision Machining) Badgasteiner Straße 2 D-28359 Bremen Tel: +49-421-2189451 Fax: +49-421-2189441 Email: qlzhao@[email protected] [email protected]

Abstract This research investigates the diamond grinding of optical glass mechanism and resulting surface and sub-surface integrity mechanism with and without ELID on a novel ultra-stiff machine tool, Tetraform ‘C’. A series of experiments was undertaken to evaluate the sensitivity of the grinding process to the machining variables and their role in defining the two important grinding regimes (brittle and ductile) which determine the corresponding surface and sub-surface properties. An acoustic emission (AE) sensor and a piezoelectric dynamometer were used to monitor the grinding process and the grinding force components correlating to different characteristics of the material removal transition. SEM and AFM microscopes were used to evaluate the ground workpiece surface and sub-surface integrity in terms of surface roughness and sub-surface damage forms and depths with the cross-sectioning method. The nano-indentation technique was applied for evaluating not only the optical glass machinability but also the potential ground glass surface properties. The results show that for optical glasses including fused silica and BK7 and fused quartz, which were ground with selected machining parameters, nanometric quality surfaces (Ra < 5 nm) with minimal subsurface damage depth (< 1μm) could be achieved with a relatively large diamond grit size (6-12μm) metal bonded grinding wheel at a high material removal rate, regardless of whether the ELID technique was employed or not, due to the ultra high closed loop stiffness of Tetraform ‘C’. Key Issues of the Work: a. Evaluating the grinding process on optical glasses in terms of AE signal, force values and surface quality. b. Quantitatively definition of the depth of sub-surface damage of different optical glasses. Status: Completed 2003 Publications of this work: Has been submitted to an academic journal.

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G16 Development of a Ductile Grinding Technology for Large Scaled Aspherical Glass Optics

Contact Information: Professor Ekkard Brinksmeier University of Bremen Faculty Production Engineering Department Manufacturing Processes Badgasteiner Str. 1 D-28359 Bremen Germany Email: [email protected] http:www.iwt-bremen.de/ft Abstract: Presently, ductile grinding of small sized glass lenses is performed by applying diamond grinding wheels with grain sizes of a few microns. This research project aims at the development of a ductile grinding technology for large scaled aspherical glass optics using coarse grained diamond wheels. The application of these wheels with diamond grain sizes of e.g. 100 µm can result in extended tool life and reduced probability of grain tear out. For reaching a suitable grinding wheel topography, a dressing technology has to be developed.

Key Issues of the Work: • development of a dressing technology • use of coarse grained diamond wheels Status: On-going Publications of this work: 1. Brinksmeier, E., Preuß, W.; Grimme, D.; Rickens, K., Advanced Strategies for the Ductile

Machining of Difficult-to-Cut Hard and Brittle Materials, Proc.of the 4th euspen International Conference, Glasgow, Scotland (2004), pp 199-200.

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G17 Development of Intelligent Grinding Tools Contact Information: Professor Ekkard Brinksmeier University of Bremen Faculty Production Engineering Department Manufacturing Processes Badgasteiner Str. 1 D-28359 Bremen Germany Email: [email protected] http:www.iwt-bremen.de/ft Abstract: The detection of the key parameters such as contact zone temperature, forces, and tool vibrations is of major importance for the determination of the process status during grinding processes. Due to the lack of appropriate measurement systems this research project comprises an integration of miniaturised sensor systems which are necessary for an in-process monitoring by the tool itself. Key Issues of the Work: • Integration of miniaturised sensor systems Status: On-going Publications of this work: 1. Brinksmeier, E.; Meyer, L., Schleifprozessüberwachung mit sensorbestückten Werkzeugen,

Autonome Produktion, Klocke, F.; Pritschow, G. (Hrsg.), Springer Verlag, 2003, pp 81-89.

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G18: Development of Low Energy and Eco-efficient Grinding Technologies

Contact Information: Professor Ekkard Brinksmeier University of Bremen Faculty Production Engineering Department Manufacturing Processes Badgasteiner Str. 1 D-28359 Bremen Germany Email: [email protected] http:www.iwt-bremen.de/ft Abstract: The objective of this project is the substantial improvement of the energy and ressource-efficiency of the grinding process by a holistic approach which addresses the entire grinding system from the machining process over the machine tool up to subsystems (e.g. filter systems). Establishing energy balances for machine tools, optimizing the coolant support in grinding and ongoing development of the grind-hardening process is the main focus of this joint project.

Key Issues of the Work: • improvement of the energy and ressource-efficieny in grinding processes Status: On-going Publications of this work: 1. Eckebrecht, J.; Kiritsis, D., Process ECO Efficiency – Technology Trend Report, Proc.

MANTYS Thematic Network on Manufacturing Technologies Conf. On “Future Trends of the Machine Tool Industry”, EMO Milano 2003, CECIMO Brüssel (Hrsg.), pp 55-68.

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G19 Development of Sensoric Grinding Tools to Prevent Grinding Burn on Components of the Driving Technology

Contact Information: Professor Ekkard Brinksmeier University of Bremen Faculty Production Engineering Department Manufacturing Processes Badgasteiner Str. 1 D-28359 Bremen Germany Email: [email protected] http:www.iwt-bremen.de/ft Abstract: To assess grinding process behavior in terms of detection of grinding burn, an in-situ detection of process temperatures in the grinding arc of contact is required. In this context, the project’s aim is to integrate a newly developed temperature sensor into a grinding tool. Strategies to detect and prevent grinding burn will be developed, which make use of the tool-based temperature measurement. Key Issues of the Work: • prevention of grinding burn • tool-based temperature measurement Status: On-going Publications of this work: 1. Brinksmeier, E.; Heinzel, C.; Meyer, L., Monitoring of Grinding Processes Using a Sensor

Equipped Grinding Wheel, Annals of the WGP Vol. XI/1 (2004), pp 41-44.

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G20 Development of Tools and Process Strategies for Surface Hardening by Internal Grinding

Contact Information: Professor Ekkard Brinksmeier University of Bremen Faculty Production Engineering Department Manufacturing Processes Badgasteiner Str. 1 D-28359 Bremen Germany Email: [email protected] http:www.iwt-bremen.de/ft Abstract: Aim of the project is the integration of heat treatment by grinding into the production line to harden the surface layer of bores. The required tools and process strategies will be tested and evaluated. Metallographic investigations and hardness measurements confirmed the possibility and the potential of the grind-hardening technology for bores.

Key Issues of the Work: • evaluation of the grind-hardening technology Status: On-going Publications of this work: 1. Brinksmeier, E.; Stöhr, R.: Wilke, T., Grundlagen und Anwendungsmöglichkeiten des

Schleifhärtens, Proc. 4. Seminar “Moderne Schleiftechnologie” (2002), Villingen-Schwenningen, pp 3-1-3-21.

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G21 Grind-hardening with Vitrified Bonded Grinding Wheels by using Grinding Fluid

Contact Information: Professor Ekkard Brinksmeier University of Bremen Faculty Production Engineering Department Manufacturing Processes Badgasteiner Str. 1 D-28359 Bremen Germany Email: [email protected] http:www.iwt-bremen.de/ft Abstract:

The heat generated in grinding processes can be used for surface layer hardening of steel components. In grind-hardening the hardening result depends on the process parameters and the grinding wheel specification. Grind-hardening tests with various grinding wheel specifications were performed to investigate correlations between the grinding wheel specification and the hardening result as well as to analyze the wheel wear. The project objective was to increase the hardness penetration depth and the stability of the grind-hardening process by using adapted grinding wheel specifications and grinding parameters. Key Issues of the Work: • grind-hardening using various grinding wheel specifications • correlation of the grinding wheel specification and the hardening result Status: On-going Publications of this work: –

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G22: Investigations on the Combined Surface Layer Heat Treatment and Finishing of Linear

Guides by Grinding in one set-up

Contact Information: Professor Ekkard Brinksmeier University of Bremen Faculty Production Engineering Department Manufacturing Processes Badgasteiner Str. 1 D-28359 Bremen Germany Email: [email protected] http:www.iwt-bremen.de/ft Abstract:

Steel components like linear guides are surface layer hardened to increase their strength properties and wear resistance. Grind-hardening is a new approach using the heat generated in the contact zone between grinding wheel and workpiece for process integrated surface layer hardening. By combining the abrasive machining and surface layer hardening, a reduction of the cycle time and manufacturing costs can be achieved. The objective of this research project was the development of dressing and grinding parameters for grind-hardening and finishing of linear guides in one set-up using the same grinding wheel specification. Key Issues of the Work: • combination of abrasive machining and surface layer hardening Status: On-going Publications of this work: –

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G23 Optimization of Coolant Supply in Grinding by Means of Flow Simulation Contact Information: Professor Ekkard Brinksmeier University of Bremen Faculty Production Engineering Department Manufacturing Processes Badgasteiner Str. 1 D-28359 Bremen Germany Email: [email protected] http:www.iwt-bremen.de/ft Abstract: The project aims on the optimization of coolant supply of the contact zone in grinding. Process conditions determined in experimental investigations are used as input parameters and boundary conditions for coolant flow modeling in shoe nozzles. Verification of the simulation is done by means of flow visualization and a method to characterize coolant effectiveness. Key Issues of the Work: • determination of process conditions • characterization of coolant effectiveness Status: On-going Publications of this work: 1. Brinksmeier, E.; Heinzel, C.; Meyer, L.; Wittmann, M., Bewertung der Effektivität der

Kühlschmierstoffzufuhr beim Schleifen, Jahrbuch “Schleifen, Honen, Läppen und Polieren”- Verfahren und Maschinen, Hrsg.: Tönshoff, H.-K.; Westkämper, E., 61. Ausgabe 2004, Vulkan-Verlag GmbH, Essen.

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G24 Reduction of Grinding Costs by Adapted Coolant Supply Contact Information: Professor Ekkard Brinksmeier University of Bremen Faculty Production Engineering Department Manufacturing Processes Badgasteiner Str. 1 D-28359 Bremen Germany Email: [email protected] http:www.iwt-bremen.de/ft Abstract: This project focuses on the influence of grinding fluid supply strategies and machining parameters on the cooling efficiency of the grinding arc. Aim of the project is the realization of a demand-oriented grinding arc supply with grinding fluid by means of experimental and analytical approaches. Key Issues of the Work: • investigation of the influence of grinding fluid supply Status: On-going Publications of this work: 1. Wittmann, M.; Heinzel, C.; Brinksmeier, E., Evaluating the Efficiency of Coolant Supply

Systems in Grinding, Annals of the WGP, Vol. XI/2, 2004.

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G25 Use of Size Effect in Grinding for Work-Hardening the Subsurface of Metal Parts Contact Information: Professor Ekkard Brinksmeier University of Bremen Faculty Production Engineering Department Manufacturing Processes Badgasteiner Str. 1 D-28359 Bremen Germany Email: [email protected] http:www.iwt-bremen.de/ft Abstract: In this project, the size effect for specific energy in grinding is analyzed and related to the work-hardening of the surface layer. The specific energy, which is defined as the energy expended per unit volume of material removal, represents a parameter for characterizing an abrasive process. The technological approach used for a controlled subsurface work-hardening of metal parts implies application of low depth of cut in combination with low cutting speed.

Key Issues of the Work: • analysis of the size effect in grinding processes • combination of low depth of cut and low cutting speed Status: On-going Publications of this work: 1. Brinksmeier, E.; Giwerzew, A., Chip Formation Mechanisms in Grinding at Low Speeds,

CIRP Annals 52 (2003), pp 253-258.

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G26 Pattern Formation and Chatter Vibration in Surface Grinding Contact Information: Prof. Dr.-Ing. Dr. h. c. K. Weinert Department of Machining Technology University of Dortmund Baroper Str. 301 D-44227 Dortmund Germany Tel: +49 231 755-2783 Fax: +49 231 755-5141 Email: [email protected] http: www.isf.de Abstract: Pattern formation in surface grinding was investigated by applying statistical design of experiments and time series analysis. No correlation between pattern formation and chatter vibration could be detected. The wavelength of visible patterns is identical to the tangential feed. The visibility of surface patterns can be reduced by increasing the tangential feed or by reducing surface waviness during sparking out with an appropriate phase-shift between current grinding wheel forced oscillation and the surface profile produced during the preceding grinding pass. Grinding wheel regenerative chatter can be suppressed by varying grinding wheel rotational speed. During oscillating surface grinding, the wheel speed can be changed when the tool is not in contact with the workpiece. The influence of a stochastic grinding wheel speed variation was investigated using this method. A concept for a controlled grinding wheel speed variation was developed. Key Issues of the Work: • Reduction of pattern formation in surface grinding • Reduction of waviness in surface grinding • Suppression of grinding wheel regenerative chatter in surface grinding Status: Completed 2004 Publications of this work: 1. Weinert, K.; Mehnen, J.; Webber, O.; Henkenjohann, N.: Optimization of the Surface

Grinding Process by Means of Modern Methods of Statistical Design of Experiments. Production Engineering – Research and Development, Annals of the German Academic Society for Production Engineering, XI (2004) 1, pp. 49-54

2. Weinert, K.; Jansen, T.; Webber, O.: Musterbildung ist unerwünscht - Strategien zur Verbesserung der Werkstückoberfläche beim Planschleifen. MM Maschinenmarkt, 110 (2004) 26, Würzburg, pp. 18-21

3. Weinert, K.; Jansen, T.; Kötter, D.; Schulte, M.; Webber, O.: Fertigungsprozesse entwickeln, verstehen und optimieren. Forum der Schneidwerkzeug- & Schleiftechnik 17 (2004) 3, pp. 10-22

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G27 FEM Grinding Process Simulation Contact Information: Professor Dr.-Ing. Dr. h. c. K. Weinert Department of Machining Technology University of Dortmund Baroper Str. 301 44227 Dortmund Germany Tel: +49 231 755 2783 Fax: +49 231 755 5141 Email: [email protected] http: www.isf.de Abstract: The simulation of the grinding process by means of the Finite-Element-Method represents a useful and powerful tool for the optimization of this process. In order to apply this method it is necessary to replace the complex grinding process by a suitable model. The goal of this project is to design models for the different grinding methods applied at the Department of Machining Technology and to apply them in each case for the optimization of the respective process. Key Issues of the Work: • Generating a model of the respective grinding process • Optimization of the process using FEM-Simulation • Verification of the FEM-results by experiments Status: In progress Publications of this work: 1.

2.

3.

Schulte, M.: Profilschleifen von Hartlegierungen und Hartverbundwerkstoffen mit konventionellen Schleifmitteln. Zur Promotion eingereichte Doktorarbeit, Universität Dortmund, 2004 Weinert, K.; Schulte, M.; Kresing, I.: Schleifprozesssimulation – Unterstützung der Prozessauslegung. IDR Industrie Diamanten Rundschau, 38 (2004) 2, pp. 156-162. Schulte, M.; Johlen, G.; Schneider, M.: Optimierung des Schleifprozesses zur Steigerung der Leistungsfähigkeit von Zerspanwerkzeugen. In: Spanende Fertigung, 3. Ausgabe Hrsg.: K. Weinert, Vulkan-Verlag, Essen, 2001, ISBN 3-8027-2925-0, pp. 581-595.

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G28 Investigations in Drilling of Fiber-Reinforced Ceramics with Abrasive Trepanning Tools Contact Information: Prof. Dr.-Ing. Dr. h. c. K. Weinert Department of Machining Technology University of Dortmund Baroper Str. 301 D – 44227 Dortmund Germany Tel: +49 231 755-2783 Fax: +49 231 755-5141 Email: [email protected] http: www.isf.de Abstract: The drilling process in fiber-reinforced ceramic is carried out with mounted points, so-called hollow drills. Aim of the investigations is the drilling process on conventional machining centres without ultrasonic support. A process optimization is achieved by modification of the tools and application of statistical design of experiments. Key Issues of the Work: • Drilling of fiber-reinforced ceramics • Grinding process with hollow drills Status: Will be completed in 2005 Publications of this work: 1. Jansen, T.: Ultraschallfreie Bohrungsbearbeitung von C/C-SiC. Seminarunterlagen,

Dortmunder Schleifseminar, ISF, Dortmund 2004 2. Weinert, K.; Jansen, T.; Kötter, D.; Schulte, M.; Webber, O.: Fertigungsprozesse entwickeln,

verstehen und optimieren. Forum der Schneidwerkzeug- & Schleiftechnik 17 (2004) 3, p. 10-22

3. Weinert, K.; Johlen, G.; Finke, M.: Bohrungsbearbeitung an faserverstärkten Keramiken, Industrie Diamanten Rundschau IDR 36 (2002) 4, p. 322-326

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G29 Internal Traverse Grinding Contact Information: Prof. Dr.-Ing. Dr. h. c. K. Weinert Department of Machining Technology University of Dortmund Baroper Str. 301 D – 44227 Dortmund Germany Tel: +49 231 755-2783 Fax: +49 231 755-5141 Email: [email protected] http: www.isf.de Abstract: For the internal traverse grinding process a grinding wheel is applied which consists of a conical zone for rough-machining and a cylindrical zone for smooth-machining. Using traverse kinematics the workpiece surface can be machined with one stroke only and at the same time with a reduced engagement zone in comparison to other internal grinding processes. Future research deals with the assessment of the thermo-mechanical load profile between grinding wheel and workpiece. The thermo-mechanical load profile characterizes the interactions between workpiece and grinding wheel indicating the surface condition of the workpiece originating from the process. Using this information the grinding wheel specification can be adjusted according to the mechanical load occurring in the specific grinding wheel zones for rough- and smooth-machining to optimize the process performance. Key Issues of the Work: • Narrow grinding wheel with a tapered roughing zone and a cylindrical finishing zone • Thermo-mechanical load profile Status: Will be completed in 2007 Publications of this work: 1. Weinert, K.; Finke, M.; Kötter, D.: Wirtschaftliche Alternative zum Hartdrehen -

Innenrundschälschleifen steigert Flexibilität beim Schleifen von Futterteilen. MM Maschinenmarkt, 109 (2003) 48, Würzburg, pp. 44-47

2. Finke, M.: Untersuchungen zur Auslegung und Optimierung des Innenrund-Längsschleifens von Futterteilen. Dissertation, Universität Dortmund, 2003

3. Weinert, K.; Finke, M.: Bohrungsbearbeitung in einem Überschliff durch Innenrund-Längsschleifen. In: 60. Jahrbuch Schleifen, Honen, Läppen und Polieren, Vulkan-Verlag, Essen, 2002, pp. 129-141

4. Weinert, K.; Finke, M.: Innenrund-Längsschleifen von Futterteilen – Bohrungen in einem Überschliff fertig schleifen. In (Hrsg.: Kazmierz E. Oczos): Proceedings der XXIV Internat. Scientific School of Abrasive Machining, Krakau – Lopuzna, 6.-9. September 2001, pp. 37-44

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G30 Process Combination Hard-Turning and Grinding Contact Information: Prof. Dr.-Ing. Dr. h. c. K. Weinert Department of Machining Technology University of Dortmund Baroper Str. 301 D – 44227 Dortmund Germany Tel: +49 231 755-2783 Fax: +49 231 755-5141 Email: [email protected] http: www.isf.de Abstract: Aim of the process combination hard-turning and grinding is to make use of the specific advantages of both processes. A two step approach for one functional face with hard-turning as a roughing process and grinding as a finishing process requires an optimized take-over condition between both processes. Consequences arising out of this process combination are a wide area of application with reduced primary processing time in comparison to the single processes. Due to small grinding overmeasures the application of a minimum quantity lubrication (MQL) system is possible for internal grinding. Key Issues of the Work: • Take-over condition between rough-turning and finishing-grinding • MQL for internal ginding Status: Completed in 2003 Publications of this work: 1. Weinert, K.; Johlen, G.: Bohrungsfeinbearbeitung durch Kombination von Hartdrehen und

Schleifen. Jahrbuch „Schleifen, Honen, Läppen und Polieren“, Hoffmeister, H.-W.; Tönshoff, H.-K. (Hrsg.), 61. Ausgabe, Vulkan Verlag, Essen, 2004, pp. 137-144.

2. Weinert, K.; Johlen, G.: Kombinierte Bohrungsbearbeitung durch Hartdrehen und Schleifen. IndustrieDiamantenRundschau IDR 37 (2003) Nr. 1/03, pp. 40-44, 2003

3. Johlen, G.: Prozessoptimierung für die Hartfeinbearbeitung durch Kombination von Hartdrehen und Schleifen. Dissertation Universität Dortmund, 2003.

4. Weinert, K.; Johlen, G.: Hartdrehen als Schruppprozess in Kombination mit Schleifen. VDI-Z 144 (2002), Nr.3 – März, pp. 69-72, Springer VDI-Verlag, Düsseldorf, 2002

5. Weinert, K.; Johlen, G.; Finke, M.: Hartdrehen und Schleifen in einer Aufspannung. ZWF 96 (2001) 5, pp. 62-67

6. Weinert, K.; Johlen, G.: Flexible Bearbeitung von Futterteilen durch Kombination der Verfahren Hartdrehen und Schleifen. In: Tagungsband „Offensivkonzepte Wirtschaftlicher Produktionstechnik“, 3. Chemnitzer Kolloquium CPK, 6. + 7. November 2001, Chemnitz, pp. 123-132

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G31 Profile Grinding with CBN Contact Information: Prof. Dr.-Ing. Dr. h. c. K. Weinert Department of Machining Technology University of Dortmund Baroper Str. 301 D-44227 Dortmund Germany Tel: +49 231 755-2783 Fax: +49 231 755-5141 Email: [email protected] http: www.isf.de Abstract: Grinding wheels with CBN are well suited for profile grinding of hard ferrous materials such as Cr- and PM-alloys. But due to the high CBN grinding wheel costs, the use of conventional grinding wheels can be more economic when grinding profiles in small batch sizes. Within this project adapted process strategies for profile grinding of Cr- and PM-alloys with conventional abrasive grains have been developed. Key Issues of the Work: • Profile grinding of Cr- and PM-alloys with conventional grinding wheels • FEM-simulation of profile grinding process Status: Completed 2003 Publications of this work: 1. Schulte, M.: Profilschleifen von Hartlegierungen und Hartverbundwerkstoffen mit

konventionellen Schleifmitteln. Zur Promotion eingereichte Doktorarbeit, Universität Dortmund, 2004

2. Weinert, K.; Jansen, T.; Kötter, D.; Schulte, M.; Webber, O.: Fertigungsprozesse entwickeln, verstehen und optimieren. Forum der Schneidwerkzeug- & Schleiftechnik 17 (2004) 3, pp. 10-22

3. Weinert, K.; Hesterberg, S.; Schulte, M.; Buschka, M.: Hochharte Schneidstoffe für die spanende Bearbeitung pulvermetallurgischer Hartlegierungen – Teil 2: Fräsen und Schleifen. IDR Industrie Diamanten Rundschau, 38 (2004) III, pp. 252-263

4. Weinert, K.; Schulte, M.: Profilschleifen hochharter Cr- und PM-Legierungen mit konventionellen Schleifmitteln. Jahrbuch „Schleifen, Honen, Läppen und Polieren“, H.-W. Hoffmeister, H.-K. Tönshoff (Hrsg.), 61. Ausgabe, Vulkan Verlag, Essen, 2004, ISBN 3-8027-2931-5, pp. 128-136

5. Weinert, K.; Schulte, M.: Schnittfreudige Schleifscheibe. MM Maschinenmarkt, 109 (2003) 37, Würzburg, pp. 24-28

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G32 Shape Grinding Contact Information: Prof. Dr.-Ing. Dr. h. c. K. Weinert Department of Machining Technology University of Dortmund Baroper Str. 301 D-44227 Dortmund Germany Tel: +49 231 755-2783 Fax: +49 231 755-5141 Email: [email protected] http: www.isf.de Abstract: Shape grinding is a suitable grinding process for manufacturing profiles. A toroid grinding wheel is lead in several paths across the workpiece. In contrast to profile grinding the paths define the shape of the workpiece. Due to this shape grinding is a very flexible manufacturing process. The small area of contact between tool and workpiece allows extremely high related material removal rates without damaging the subsurface zone. Key Issues of the Work: • Analysis of the complex area of contact between grinding wheel and workpiece • Economic comparison of profile grinding vs. shape grinding Status: Will be completed 2005 Publications of this work:

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G33 Tool Grinding Contact Information: Prof. Dr.-Ing. Dr. h. c. K. Weinert Department of Machining Technology University of Dortmund Baroper Str. 301 44227 Dortmund Germany Tel: +49 231 755 2783 Fax: +49 231 755 5141 Email: [email protected] http: www.isf.de Abstract: Grinding of tools for manufacturing and conditioning represents a thermo-mechanical load for the respective tool. This load affects the peripheral zone of the tool and can significantly influence its application and wear properties. After designing a suitable model for the simulation of tool grinding, the researcher has focused on the reduction of heat flux into the tool and mechanical deformation of the tool by varying the process strategy (e.g. adjusting cutting speed, infeed and feed speed), applying different types of grinding wheels and machining different cutting-materials. Key Issues of the Work: • Generating a model of the tool grinding process • Optimization of grinding-parameters • Compensation of deformation caused by thermo-mechanical loads Status: Completed 2004 Publications of this work: 1.

2.

3.

4.

5.

Weinert, K.; Jansen, T.; Kötter, D.; Schulte, M.; Webber, O.: Fertigungsprozesse entwickeln, verstehen und optimieren. In: Forum der Schneidwerkzeug- & Schleiftechnik 17 (2004) 3, pp. 10-22. Weinert, K.; Schulte, M.; Kresing, I.: Schleifprozesssimulation – Unterstützung der Prozessauslegung. IDR Industrie Diamanten Rundschau, 38 (2004) 2, S. 156-162. Weinert, K.; Schulte, M.: Kompensation der prozessbedingten Deformation beim Werkzeugschleifen. wt Werkstattstechnik online, Springer Verlag, Düsseldorf, 93 (2003) 7/8, pp. 550-554. Schulte, M.; Johlen, G.; Schneider, M.: Optimierung des Schleifprozesses zur Steigerung der Leistungsfähigkeit von Zerspanwerkzeugen. In: Spanende Fertigung, 3. Ausgabe Hrsg.: K. Weinert, Vulkan-Verlag, Essen, 2001, ISBN 3-8027-2925-0, pp. 581-595. Schneider, M.: Auswirkungen thermomechanischer Vorgänge beim Werkzeugschleifen. Dissertation, Universität Dortmund, 2000

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G34 Burr Formation in Surface Grinding of Tool Steel Contact Information Professor Jan C. Aurich Institute for Manufacturing Engineering and Production Management – FBK University of Technology Kaiserslautern P.O. Box 3049 D-67653 Kaiserslautern, Germany Email: [email protected] http: www.uni-kl.de/FBK/ Abstract: Recent research on burr formation in metal cutting has primarily focused on processes with defined tool geometry such as turning, milling or drilling. In this project fundamental investigation of burr formation in flat surface grinding of tool steel is conducted, using conventional and superabrasive grinding wheels with different grain sizes and materials under varying cutting conditions. The geometry of the generated exit burrs at the workpiece edge are investigated and characteristic geometrical burr parameters, e. g. burr thickness at root and burr height, are measured. Furthermore, measured grinding forces and temperatures are related to the grinding wheel type and correlated to the characteristic burr parameters. In addition, the microstructure of the burr material is analyzed by metallographic sections. Beside the experimental investigations, the thermo-mechanical FE-Modeling of burr formation in grinding has been investigated by using commercial Finite Element Analysis (FEA) codes. During this project burr formation in grinding could be simulated for the first time. As result of both investigations a theory of burr formation mechanism in grinding, which is comparable to the burr formation in processes with defined cutting edges, has been developed. Key Issues of the Work: • Burr formation in grinding • FEM analysis of burr formation Status: On-going Publications of this work: 1. Barth, C.; Dollmeier, R.; Warnecke, G.: Burr Formation in Grinding of Hardened Steel with

Conventional and Superabrasive Wheels. Technical Papers of the NAMRI/SME 2001, 29th North American Manufacturing Research Conference (NAMRC XXIX), Gainesville, FL, USA, pp. 270/1-270/6.

2. Aurich, J. C.; Sudermann, H.; Braun, O.: “Experimental investigation of burr formation in surface grinding of tool steel”, Proceedings of 7th International Conference on Deburring and Surface Finishing, 2004, Berkeley, CA, USA, pp. 29-37.

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G35 Design of Grinding Wheel Hubs Using the Finite Element Method Contact Information Professor Jan C. Aurich Institute for Manufacturing Engineering and Production Management – FBK University of Technology Kaiserslautern P.O. Box 3049 D-67653 Kaiserslautern, Germany Email: [email protected] http: www.uni-kl.de/FBK/ Abstract: Experimental investigations prove that the hub of the grinding wheel has considerable influence on the process when grinding hard and brittle materials such as advanced ceramics. The dynamic properties of the hub affect the dynamic contact zone conditions which influence the material removal mechanism and, thus, the whole process. Diverse, coupled influence-cause-effect relationships between the vibration excitation due to the grinding process, the system behavior and the contact behavior have been analyzed using a transient finite element simulation. The thermal properties of the hub are of minor importance. For the grinding of hard and brittle materials it seems to be useful to use yielding, high damped hubs with reinforced borders. The hub of the grinding wheel is an influence quantity that is equally important as bonding, cutting parameters and the specification of the machine system. Within future process planning strategies, the hub has to be considered to an increased extend and should al-ways be specified. Key Issues of the Work: • Grinding of hard and brittle materials • Vibrations in HEDG • Design of grinding wheel hubs Status: Finished Publications of this work: 1. Warnecke, G.; Barth, C.: Design of Hubs of Grinding Wheels for Grinding Hard and Brittle

Materials, Annals of the WGP Vol. IX (2002), pp. 123-126. 2. Warnecke, G.; Barth, C.: Optimization of the Dynamic Behavior of Grinding Wheels for

Grinding of Hard and Brittle Materials Using the Finite Element Method, Annals of the CIRP 48/1 (1999), pp. 261-264.

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G36 Kinematic Simulation for Analyzing and Predicting High-Performance Grinding Processes Contact Information Professor Jan C. Aurich Institute for Manufacturing Engineering and Production Management – FBK University of Technology Kaiserslautern P.O. Box 3049 D-67653 Kaiserslautern, Germany Email: [email protected] http: www.uni-kl.de/FBK/ Abstract: In grinding technology, the application of superabrasives and increasing demands for higher productivity and higher quality require an appropriate selection of optimum set-up parameters. Therefore, the development of analytical or empirical models for reliable prediction of machining performance and work results is a key issue. This paper presents a comprehensive concept for process modeling which provides a software tool for analyzing and designing high performance grinding processes, using the method of kinematic simulation. On the basis of synthetic 3D-models describing the macro- and micro-geometry of the grinding wheel and the workpiece, together with mathematical models describing the relative motions and kinematic engagement conditions, grinding processes can be reproduced as the accumulation of multiple grit engagements. The proposed simulation tool allows the generation of optional grinding wheel topographies and the analysis and prediction of the machining performance and work result for different grinding techniques, taking into account thermo-mechanical and dynamic effects in the contact area. Key Issues of the Work: • Modeling and simulation of grinding processes • Process optimization • Superabrasive grinding tools Status: Finished Publications of this work: 1. Warnecke, G.; Zitt, U.: Kinematic Simulation for Analyzing and Predicting High-

Performance Grinding Processes, Annals of the CIRP 47/1 (1998), pp. 265-270. 2. Zitt, U.; Braun, O.; Warnecke, G.: Improvement of Workpiece Quality of Ceramic Engine

Valves by Kinematic Simulation of the Valve Grinding Operation, Transactions of the NAMRC/SME 2004, 27th North American Manufacturing Research Conference (NAMRC XXVII), Berkeley, CA, USA, pp. 153-158.

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G37 Superabrasive Grinding Wheel With Defined Grain Structure Contact Information Professor Jan C. Aurich Institute for Manufacturing Engineering and Production Management – FBK University of Technology Kaiserslautern P.O. Box 3049 D-67653 Kaiserslautern, Germany Email: [email protected] http: www.uni-kl.de/FBK/ Abstract: A concept of superabrasive electroplated grinding wheels based on defined grain structures was developed. The aim is to minimize heat generation, reduce grinding forces and improve process stability, while preserving a high material removal rate. Based on geometrical models, different patterns of grit settings have been investigated by means of kinematic simulation. Applying the results of the simulation, a prototype grinding wheel with an optimized defined grain structure has been constructed. The potential of the prototype to lower forces and temperatures significantly has been proofed through experimental examinations using specific material removal rates up to 100 mm³/(mms). Key Issues of the Work: • Tool development in superabrasive grinding • Grinding wheel with defined grain structure • Kinematic simulation of grinding processes Status: Finished Publications of this work: 1. Aurich, J.C.; Braun, O.; Warnecke, G.: Development of a Superabrasive Grinding Wheel

With Defined Grain Structure Using Kinematic Simulation, Annals of the CIRP 52/1 (2003), pp. 275-280.

2. Braun, O.; Warnecke, G.; Aurich, J.C.: Simulation-based Development of a Superabrasive Grinding Wheel With Defined Grain Structure, paper proposal for: Transactions of the NAMRI/SME 2005, 33rd North American Manufacturing Research Conference (NAMRC 33), Columbia University, New York, NY, USA, May 24-27, 2005.

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G38 Ultrasonic Superimposed Grinding of Advanced Ceramics Contact Information Professor Jan C. Aurich Institute for Manufacturing Engineering and Production Management – FBK University of Technology Kaiserslautern P.O. Box 3049 D-67653 Kaiserslautern, Germany Email: [email protected] http: www.uni-kl.de/FBK/ Abstract: Ultrasonic superimposed grinding represents a modification of the conventional pendulum grinding process. The grinding wheel rotation in workpiece feed direction is superimposed by a high-frequency vibration of the workpiece in grinding wheel axis direction. As a result of this workpiece vibration there is a change in the removal behavior of silicon carbide ceramics, so there is no “jagged” surface micro topography as in conventional pendulum grinding, but a more “smoothed over” structure that is less prone to detachment of individual particles and thus appears better suited for tribo-mechanically loaded function surfaces in silicon carbide ceramic. Key Issues of the Work: • Grinding of advanced ceramics • Ultrasonic superimposed grinding • Material removal behavior Status: Finished Publications of this work: 1. Warnecke, G.; Zapp, M.: Ultrasonic Superimposed Grinding of Advanced Ceramics, 1st

International Machining and Grinding Conference, SME Technical Paper MR95-169 (1995), Dearborn, MI, USA, pp. 139-149.

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G39 Grinding of γ-Titanium-Aluminides Contact Information: Professor Fritz Klocke WZL - Machine Tool Laboratory Aachen University Steinbachstrasse 53 D - 52074 Aachen Germany Tel: +49 241 802 7401 Fax: +49 241 802 2293 Email: [email protected] http: www.wzl.rwth-aachen.de Abstract: γ-titanium aluminides are a novel material with great potential for use in the aviation, gas turbine, and automotive industries. Due to their high specific strength and their stability at high temperatures, these materials will be particularly important for the aeronautics industry. To design a practical manufacturing process for products made of γ-titanium aluminides, both preliminary experiments and grinding tests are required, with particular attention being paid to product quality. • Preliminary experiments: Titanium aluminides are relatively brittle materials. Their ductility

at low temperatures greatly affects the chip removal and cutting mechanisms. Preliminary experiments, comprising of single grit scratching tests, must first be conducted, to analyse the abrasive properties of different grit materials such as CBN and diamond.

• Grinding of γ-titanium aluminides: The machining of titanium aluminides is based on the intermetallic γ- and α2-phases, and is characterised by a high load collective of the cutting tool. How-ever, increasing demands on titanium-based alloys, particularly in turbine engineering, have raised the standards for the quality, productivity and flexibility of grinding processes. To meet this demand, a grinding strategy is developed, which takes into consideration the properties of the materials as well as data on wear mechanisms that were obtained from the single grit scratching tests conducted with different kinds of grit materials. Technological and economical machining parameters for these novel materials will be deter-mined in grinding and dressing experiments, and evaluated with respect to their process capability.

Key Issues of the Work: • γ-titanium aluminides • hard to machine materials • aircraft engine materials Status: Completed 2004 Publications of this work: See homepage of www.wzl.rwth-aachen.de

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G40 Reduction of Cooling Lubricants and Environmentally Compatible Grinding Contact Information: Professor Fritz Klocke WZL - Machine Tool Laboratory Aachen University Steinbachstrasse 53 D - 52074 Aachen Germany Tel: +49 241 802 7401 Fax: +49 241 802 2293 Email: [email protected] http: www.wzl.rwth-aachen.de Abstract: In grinding a large quantity of heat is created due to cutting and friction operations at the shear plane and the cutting zone as well as at the friction zone on the clearance, the rake plane and the bonding. The heat introduced to the process can only be transported away partly by the chips and can lead to thermal workpiece damage. Because of that, cooling lubricants come into operation, whose reduction is much harder for grinding than in machining processes with geometrically defined cutting edge. Cooling lubricants act as an intermediary medium in the tribological system of the grinding contact zone. Apart from lubricating the contact area the cooling lubricant has further tasks like cooling, chip transport and cleaning the tool and the workpiece. The lubrication effect strongly depends whether the cooling lubricant gets to the contact zones and whether it is able to generate effective, mechanical stable layers between tool and workpiece material, which reduce friction and wear. In particular, the application of minimum quantity lubrication, that is characterised by a very low cooling effect, demands knowledge about the tribological interaction between grit, bonding, coolant, workpiece material and atmosphere.

Furthermore, the characteristic of the cooling lubricant, consisting of a base fluid and different additives when using minimum quantity lubrication, is decisive for recording these active principles. The wetting behaviour and the adhesion ability between coolant and grinding wheel influence among other things the amount of coolant required. The aim of a sucessful use of cooling lubrication is a burn-free workpiece rim zone after machining. To design the necessary coolant flow rate and to evaluate the structure of the workpiece rim zone the amount of heat introduced to the prozess respectively to the workpiece can be determined by software based simulation programs. Key Issues of the Work: • Coolant reduction • Environmentally compatible grinding Status: running Publications of this work: See homepage of www.wzl.rwth-aachen.de

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G41 Artificial Intelligence in Grinding Contact Information: Professor Fritz Klocke WZL - Machine Tool Laboratory Aachen University Steinbachstrasse 53 D - 52074 Aachen Germany Tel: +49 241 802 7401 Fax: +49 241 802 2293 Email: [email protected] http: www.wzl.rwth-aachen.de Abstract: The grinding process is described by a variety of influencing variables. Among others the grinding task, the process parameters and the obtained process result belong to them. Due to these parameter varieties the control of the grinding process requires an extensive expert knowledge as well as theoretical and practical experiences. Usually expert knowledge remains reserved for only a few coworkers, whose wealth of experience is not accessible to other users. Therefore in grinding in particular the process layout and process optimization are often possible only by a large number of preliminary tests according to the principle "Try and error!". Artificial Neural Networks offer an alternative to a empirical or physical description of the grinding process. Their distinct self-learning ability enables the simple and automated creation of process models and the fast adjustment of these models to changed boundary conditions. Besides that the generalization ability of artificial neural networks enables the simulation of grinding processes without expert knowledge and on the basis of only a few preliminary tests. During the layout of the grinding process finding a possible and target-oriented combination of the grinding parameters means not necessarily that this also represents the optimal solution. Since in grinding the process-result can be achieved by different strategies, the process optimization therefore is not identical to the process layout. Finding the process optimum can be achieved via the application of genetic algorithms. Key Issues of the Work: • Grinding process design and optimization by Neural Networks and Artificial intelligence Status: running Publications of this work: See homepage of www.wzl.rwth-aachen.de

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G42 CBN-Highspeed Grinding of CVT Gear Shafts with Minimum Quantity Lubrication Contact Information: Professor Fritz Klocke WZL - Machine Tool Laboratory Aachen University Steinbachstrasse 53 D - 52074 Aachen Germany Tel: +49 241 802 7401 Fax: +49 241 802 2293 Email: [email protected] http: www.wzl.rwth-aachen.de Abstract: High performance external traverse grinding with CBN enables a high flexibility concerning machinable workpiece features as well as significant increases in material removal rates compared to conventional grit materials. In the ULTRAFLEX project, which is founded by the European Community, a high- productive and quality oriented process chain for manufacturing shaft type parts like CVT gear shafts is developed. In order to improve the process chain including environmental consciousness, all manufacturing steps of both unhardened and hardened components are considered and will be optimised. As part of the hard machining a strategy for CBN- high speed peel grinding with minimum quantity lubrication is developed. Here, different workpiece features are machined with one geometrical adapted grinding wheel. • High speed grinding: For grinding with CBN several improvements can be obtained by the

application of the high speed technology. The advantages of higher cutting speeds can be used either for economy grinding to increase the material removal rate at constant workpiece quality or for quality grinding to improve the surface roughness at a constant cutting performance.

• Minimum quantity lubrication: The minimum quantity lubrication works with coolant haze, fed to the cutting location by compressed air. This technology enables a reduction of the coolant flow rate to values smaller than 50 ml/h. Due to the low cooling effect when applying minimum quantity lubrication there is a high tendency to thermal workpiece damage. To ensure a burn-free machining process the adaption of the entire system consisting of machine tool, grinding wheel and cooling lubricant is necessary.

Key Issues of the Work: • minimum quantity lubrication • CBN high-speed grinding Status: completed 2004 Publications of this work: See homepage of www.wzl.rwth-aachen.de

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G43 Chaos-Theory: Potentials in Grinding Contact Information: Professor Fritz Klocke WZL - Machine Tool Laboratory Aachen University Steinbachstrasse 53 D - 52074 Aachen Germany Tel: +49 241 802 7401 Fax: +49 241 802 2293 Email: [email protected] http: www.wzl.rwth-aachen.de Abstract: Owing to the stochastic properties of the grinding tool, the large number of influencing variables and the complex kinematic contact parameters involved, grinding is an extremely complex production process, highly inaccessible to deterministic description. As a result, on-line quality monitoring during grinding process operations entails the use and development of analytic methods and diagnostic systems adapted to the complexity of the process. Two research projects funded by the Volkswagen- Stiftung are intended to provide methods of non-linear dynamic analysis for grinding operations. • Signal analysis: Analysis of interrelationships between sensor signals, process variables and

quality attributes of the part. Attributes, parameters and functions characterising non-linear system behaviour are employed to obtain an improved description of the grinding process. On the basis of this description, self-organising neural networks are used to develop empirical models describing the identified relationships and enabling prediction of the process outcome.

• Topographic analysis:Topographic analysis of the cutting surface of the grinding wheel and the ground part surface using non-linear dynamics and fractal geometry methods. By means of these analytic techniques correlations between the respective surface profiles of the tool and the part shall be determined, which can be utilised for monitoring the grinding process. A description of the identified relationships will also be provided by means of empirical modeling in a neural network.

Key Issues of the Work: • Chaos theory • Artificial intelligence Status: Completed 2002 Publications of this work: See homepage of www.wzl.rwth-aachen.de

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G44 Characterisation of Vitrified-bonded CBN Grinding Wheels Contact Information: Professor Fritz Klocke WZL - Machine Tool Laboratory Aachen University Steinbachstrasse 53 D - 52074 Aachen Germany Tel: +49 241 802 7401 Fax: +49 241 802 2293 Email: [email protected] http: www.wzl.rwth-aachen.de Abstract: Vitrified-bonded CBN grinding wheels find increasing industrial application, since they are easy to dress and achieve a high performance. Although numerous parameters affect the manufacturing process, no universally informative test method could be developed for vitrified-bonded CBN grinding wheels so far. If a suitable test method can be introduced, quality testing of grinding wheels will become much more conclusive. There will also be a decisive advantage for the user through the possibility to compare grinding wheels from different manufacturers. A universal test method will, moreover, enable us to classify CBN grinding wheels. The object of this re-search project is to carry out fundamental scratch test research on the grinding abrasive, aiming at the development of a test method for vitrified-bonded CBN grinding wheels. The grinding wheels will be characterised by analysing the force and acoustic emission spectrum during the scratch test. The objective of this test method is to determine the hardness of the grinding wheel its wear resistance and the homogeneity of the abrasive by means of this test method. Following initial signal analysis tests on single grit break-outs, a test method for scratch tests will be developed. The advantages of scratch tests lie in their much shorter test time and high potential for automation. The planned studies will examine the influence of the grinding wheel specification parameters grit size, grit concentration, pore space and hardness with regard to the force and acoustic emission spectrum. Key Issues of the Work: • Testing method for vitrified bonded cBN grinding wheels • Characterisation of grinding wheels Status: Completed 2004 Publications of this work: See homepage of www.wzl.rwth-aachen.de

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G45 Examinations on Grinding-Wheels made of Sol-Gel-Corundum Contact Information: Professor Fritz Klocke WZL - Machine Tool Laboratory Aachen University Steinbachstrasse 53 D - 52074 Aachen Germany Tel: +49 241 802 7401 Fax: +49 241 802 2293 Email: [email protected] http: www.wzl.rwth-aachen.de Abstract: By manufacturing grinding tools the choice of the grinding material has a central relevance. The bonding composition decides in a significant way about the wear resistance and process behaviour of the grinding tool. Developed in the industry, a new grinding material, called Sol-Gel-Corundum, has come up. Because of its productive efficiency Sol-Gel-Corundum closes the gap between the very hard (Diamond and CBN) and the conventional (Fused corundum and Silicon carbide) grinding materials. For the optimized use of grain material in grinding wheels the knowledge of the embedding-mechanisms is urgently required. To enable the postulated knowledge basic examinations on grinding materials and bonding systems are necessary. The aim of research at the WZL is the examination of the interface between grain and bonding of grinding wheels to determine the embedding-mechanisms. Therefore methods of instrumental analysis are used to characterise grinding wheels concerning their chemical and physical properties. Key Issues of the Work: • Sol-Gel-Corundum • Grain - bonding interface Status: In Progress Publications of this work: See homepage of www.wzl.rwth-aachen.de

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G46 Flexible High Performance Hard-End-Machining (HHFlex) Contact Information: Professor Fritz Klocke WZL - Machine Tool Laboratory Aachen University Steinbachstrasse 53 D - 52074 Aachen Germany Tel: +49 241 802 7401 Fax: +49 241 802 2293 Email: [email protected] http: www.wzl.rwth-aachen.de Abstract: Up to now, high performance processes, like hard-turning, cBN-peal-grinding and hard roller burnishing, can operate only in small processing areas. While reaching the quality demanded, they achieve a high productivity but only a low flexibility. Further on, the process limits of this finishing processes are only known insufficiently. So far, executed studies have only qualitative nature and do not allow a straight comparability and the determination of selection criteria for the process selection. The target in the HHFlex project, which is founded by the federal ministry for education and research, is the technological investigation and selection of process-chains for hard-finishing operations by considering economical aspects. Therefore, the machining operations hard-turning, cBN-grinding and hard-roller burnishing should be integrated in one machine tool for the sequential and simultaneous machining of hardened shaft components. Main project targets are: • Determination of the process limits of the integrated hard finishing operations (as single

process and process combination) • Definition of suitable selection criteria for the validation of processes / process-chains for

hard finishing operations • Technological and economic consideration and selection of alternative process-chains for

hard finishing operations • Development of a geometry based process strategy for hard finishing operations Prior target of this project is a technological based comparison of the manufacturing processes hard-turning and cBN-grinding in combination with hard roller burnishing with the intention of a sequential and/or simultaneous process strategy. By using a suitable test method and a simultaneous criteria development, an expert system will be evolved. Key Issues of the Work: • Combined/ simultaneous machining • Hard-end-machining Status: Running Publications of this work: See homepage of www.wzl.rwth-aachen.de

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G47 Fundamental Research of the Grain Wear Behavior Contact Information: Professor Fritz Klocke WZL - Machine Tool Laboratory Aachen University Steinbachstrasse 53 D - 52074 Aachen Germany Tel: +49 241 802 7401 Fax: +49 241 802 2293 Email: [email protected] http: www.wzl.rwth-aachen.de Abstract: When dressing superabrasive grinding wheels even the newest generations of dressing tools are subjected to wear. Besides the micro wear mechanisms diffusion, adhesion, abrasion and tribo-oxidation, this wear is based on the impact stress of the dressing grains during the dressing process. For fundamental research of the grain wear behaviour a pendulum designed and built at the WZL facilitates simulations of the impact between two hard materials. By considering elastomechanical basics and aspects of tribology the influences of the impact kinematics and contact conditions can be analysed. The pendulum fixture simulates the impact of a momentum afflicted hard grain on a fixed impact partner under variable contact conditions. Concerning this application the necessary requirements for the pendulum are: • Global system stiffness • Trajectory accuracy • Accuracy of positioning • Impulse variance • Reproducibility • Flexibility Prospect: The test rig promises a meaningful analysis of the impact between two hard materials on the basis of single grain impact tests. The transferability on wear mechanisms in dressing and grinding of hard materials ought to be verified in real tests. Key Issues of the Work: • Grain wear behaviour • Fundamental research Status: Running Publications of this work: See homepage of www.wzl.rwth-aachen.de

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G48 Grinding Of Nickel-Based Alloys Contact Information: Professor Fritz Klocke WZL - Machine Tool Laboratory Aachen University Steinbachstrasse 53 D - 52074 Aachen Germany Tel: +49 241 802 7401 Fax: +49 241 802 2293 Email: [email protected] http: www.wzl.rwth-aachen.de Abstract: Nickel-based alloys are the most commonly-used materials subjected simultaneously to high dynamic stresses and high operating temperatures. Owing to the severe demands on quality, flexibility and productivity, grinding operations on these materials are an integral component of the manufacturing process sequence. Due to their great high-temperature strength, their low thermal conductivity and the abrasive effects of carbides and intermetallic phases, nickel-based alloys are regarded as hard-to-machine materials. The advantages of grinding with cubic boron nitride (CBN) are exploited for machining operations on nickelbased alloys. With its high wear resistance, good dressability and potential for systematic design of the grinding abrasive, the vitrified –bonded CBN grinding wheel offers special possibilities for flexible, productive and quality-oriented manufacturing. Machining strategies. CD-(continuous dressing) grinding operations have been the preponderant grinding process for nickel-based alloys, so far. Using this machining process, high process reliability and material removal rates are opposed to less flexibility and high set-up times. An approach to increase flexibility, productivity and workpiece quality, simultaneously, is the process substitution with CBN grinding. For this, two alternative strategies are: the flexible five-axis-machining of compressor and turbine components and speed stroke grinding with table velocities up to vw = 200 m/min. Key Issues of the Work: • Grinding of nickel-based alloys with vitrified bond CBN grinding wheels • CD-grinding as alternative process • Speed stroke grinding Status: running Publications of this work: See homepage of www.wzl.rwth-aachen.de

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G49 High Productive Centerless Grinding with CBN Contact Information: Professor Fritz Klocke WZL - Machine Tool Laboratory Aachen University Steinbachstrasse 53 D - 52074 Aachen Germany Tel: +49 241 802 7401 Fax: +49 241 802 2293 Email: [email protected] http: www.wzl.rwth-aachen.de Abstract: Within a research project, funded by the European Commission, contract n° BRPR-CT98-0709, CBN-technology for centerless grinding processes is developed. The consortium consists of 8 partners from four European countries. The end-users (TRW, Iveco, Torunsa) use an expertise in the fields of measurement (Marposs), lubrication (Fuchs), grinding tools (St. Gobain), machine tool (Modler) and a research institution (WZL-RWTH-Aachen) for developing a high productive CBN-centerless grinding process with cutting speeds up to vs = 150 m/s. In order to fulfil high quality requirements of the end-user parts, new measurement concepts for the surveillance of workpiece hardness, crack formations, gaging, crash control, dressing and roundness error formation are integrated into the grinding system. New lubrication concepts allow a reduction of the required amount of coolant down to 1,7 l/min, referred to one millimetre width of the active grinding layer. Environmental restrictions concerning coolant disposal and a human reconcilable working environment have been acquired. The development of new grinding tools allows high productive grinding at cutting speeds up to vs = 150 m/s. Herein the technological demands on the machine tool have been performed by adequate spindle-, drive- and stiffness concepts by the machine manufacturer Modler. In practical tests, the grinding time in plunge feed grinding of knuckle pins from IVECO could be reduced by 68% by using this innovative CBN-grinding process. Further investigations are centerless plunge feed grinding of engine valves from TRW and centerless through feed grinding of automotive parts from Torunsa. In centerless through feed grinding applications, an adequate set up of the grinding gap is of high significance. In practical tests the CBN-technology is compared with a centerless grinding process, where conventional grinding materials are used. One noteworthiness of the research project is the development of an “intelligent workrest blade”. Different concepts of sensor- and actor-systems are examined for a stable use of this high productive manufacturing process. Key Issues of the Work: • Centerless Grinding with CBN • Roundness error prediction Status: Completed 2002 Publications of this work: See homepage of www.wzl.rwth-aachen.de

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G50 High-Speed-Grinding with Microcrystalline Al2O3 Contact Information: Professor Fritz Klocke WZL - Machine Tool Laboratory Aachen University Steinbachstrasse 53 D - 52074 Aachen gERMANY Tel: +49 241 802 7401 Fax: +49 241 802 2293 Email: [email protected] http: www.wzl.rwth-aachen.de Abstract: The use of grinding wheels containing microcrystalline Al2O3 at circumferrential-speeds ranging from vc = 63 m/s up to vc = 180 m/s and high removal rates with varying process-parameters. A process strategy will be developed for a stable and economical application within high-speed-machining when grinding wheels, containing microcrystalline Al2O3, are used at high cutting-speeds. Different grinding-wheel-specifications will be analysed, for their application behaviour. Two different types of grinding wheels are tested: Full-body grinding wheel (vs < 125 m/s), metal body and a segmented layer (vs > 125 m/s)

• Grinding parameters: Grinding speed: vs = 63 – 180 m/s, spec. removal rates: Q`w ≥ 100

mm3/mms • Workpiece materials: Roller-bearing-steel 100Cr6V, case hardened-steel 20MoCr4, high-

speed-steel HS6-5-2 To evaluate the application behaviour of the Sol-Gel-grinding-wheels for example the grinding forces and process results are compared. In further reference examinations the application behaviour will be compared to cBN grinding wheels with ceramic bonding and Ekw grinding wheels. Key Issues of the Work: • High speed grinding with conventional grit materials • microcrystalline Al2O3 Status: Completed 2002 Publications of this work: See homepage of www.wzl.rwth-aachen.de

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G51 Measures For Reduction Of Roundness Errors In Centerless Grinding Processes Contact Information: Professor Fritz Klocke WZL - Machine Tool Laboratory Aachen University Steinbachstrasse 53 D - 52074 Aachen Germany Tel: +49 241 802 7401 Fax: +49 241 802 2293 Email: [email protected] http: www.wzl.rwth-aachen.de Abstract: Rounding mechanisms in centerless grinding were observed by Kirner already in 1933, describing among other things special types of polygonal structures within this type of machining process. Results from the subsequent research activities led to a classification of three relevant characteristics, responsible for roundness errors in centerless grinding: regenerative chattering, geometrical rounding effects and process characteristically disturbances. By considering specific oscillation characteristics of the machine tool, process parameters are chosen adequately, so that chatter-oscillations can be neglected. Main issue within the reduce of roundness errors in centerless grinding is the development of an active workpiece stimulation strategy and a new generation of work rest blades hereto. Within the mathematical approach of the rounding mechanisms, a simulation model is developed and will be improved steadily. Thus rounding effects can be simulated in advance, in order to find an adequate range of geometrical set up parameters of the grinding gap before grinding. The outcome of this is a design of a new stability diagram for stable grinding conditions and a verification of such results in practical grinding examinations. In this connection set-up recommen-dations with respect to a specific workpiece geometry and traverse possibilities of the machine tool can be given. Long-term objective of this special research activity is the development of a modular work rest blade for a self-induced stability control of process stability and quality in centerless grinding applications. Key Issues of the Work: • Centerless grinding • Roundness error reduction Status: Completed 2002 Publications of this work: See homepage of www.wzl.rwth-aachen.de

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G52 Software Engineering with Respect to Grinding Contact Information: Professor Fritz Klocke WZL - Machine Tool Laboratory Aachen University Steinbachstrasse 53 D - 52074 Aachen Germany Tel: +49 241 802 7401 Fax: +49 241 802 2293 Email: [email protected] http: www.wzl.rwth-aachen.de Abstract: Based on the experience from various fundamental and application-oriented research projects in the field of grinding technologies a considerable process knowledge was gained. This knowledge is now consequently transferred to software-applications to support technology planning and process optimisation in grinding processes. Until now the following software products have been or are developed: • APOS – automatic process optimisation software for all grinding techniques based on a

database and supported by artificial intelligence • CEGRIS – process optimisation in centerless grinding • HHFlex – strategies for hard-end machining (grinding, hard-turning and roller-burnishing) Key Issues of the Work: • Development of expert systems • Process planning • Process optimisation Status: running Publications of this work: See homepage of www.wzl.rwth-aachen.de

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G53 Speed Stroke Grinding- a New Technology with High Potential Contact Information: Professor Fritz Klocke WZL - Machine Tool Laboratory Aachen University Steinbachstrasse 53 D - 52074 Aachen, Germany Tel: +49 241 802 7401 Fax: +49 241 802 2293 Email: [email protected] http: www.wzl.rwth-aachen.de Abstract: The aeronautic industry has high standards for safety and reliability of its products, since the various components of aircraft engines are exposed to extreme thermal and mechanical stress. Materials used in the aeronautics as well as the automotive industry are commonly nickel- and titanium-based. An economical machining process of these hard to machine materials must also allow a high degree of tolerance. • To address this problem, a new manufacturing strategy called “speed stroke grinding” was

developed. It aims to minimise machining time and costs by increasing workpiece speed while improving the quality of the grinding process. The application of this novel strategy requires a new efficient grinding machine, with linear drives, optimised grinding tools, and an adapted coolant supply system.

• Single grit scratching tests were conducted to investigate the effects of superabrasive grit materials on nickel-based alloys and titanium aluminides. The abrasive properties of cubic boron nitride (CBN) and diamond were determined under conditions independent of the bond system. Based on these test results as well as on FEM simulations of the grinding wheel body, the grinding tool was optimised and adapted to the manufacturing process.

• The process quality, and thus the product quality, is affected by many complex and non-independent factors. In order to develop a technologically and economically machining process, these factors must be taken into consideration. In particular, due to the use of long chipping materials, the dressing conditions affect the grinding behaviour and thus require the generation of an appropriate grinding wheel topography. Also, high table travel velocities produce a high single chip thickness, which in turn affects the wear- and material removal mechanisms. This must therefore be taken into account. This new strategy should lead to the increased use of superabrasive grit materials and development of novel applications

Key Issues of the Work: • Speed stroke grinding of aircraft engine materials • Single grit scratching tests • Development of a machining strategy for speed stroke grinding Status: completed in 2004 Publications of this work: See homepage of www.wzl.rwth-aachen.de

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G54 Tool Grinding Contact Information: Professor Fritz Klocke WZL - Machine Tool Laboratory Aachen University Steinbachstrasse 53 D - 52074 Aachen Germany Tel: +49 241 802 7401 Fax: +49 241 802 2293 Email: [email protected] http: www.wzl.rwth-aachen.de Abstract: In the field of defined cutting, the use of cutting materials with a extremely high hardness increases. These materials, like cemented carbides, cermets or poly cristalline diamonds, make high demands on the manufacturing of the cutting tools. Due to their physical properties, like high hardness and wear resistance the available production techniques are limited. Among other reasons the application of these cutting materials depends on the efficiency of the manufacturing process of the cutting tools. Therefore an optimised tool grinding process is necessary. Research in tool grinding at WZL concentrates on the improvement of the quality and efficiency of the process. Key Issues of the Work: • Tool grinding • Polycrystalline diamond Status: Completed Publications of this work: See homepage of www.wzl.rwth-aachen.de

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G55 Efficient CD Grinding Contact Information: Dr.-Ing. Hans-Werner Hoffmeister Institute of Machine Tools and Production Technology Technical University Braunschweig Germany Tel: +49 531 391 7606 Fax: +49 531 391 5842 Email: [email protected] http: www.iwf.ing.tu-bs.de Abstract: The use of continuous dressing grinding processes (CD-grinding) instead of the conventional grinding enhances the process efficiency regarding the material removal rate. On the one hand a dressing parallel to the grinding process maintains the cutting ability of the grinding wheel and on the other hand the grinding wheel wear can be neglected if the process lay out is correctly done. The result is a dramatically reduced machining time at moderately increasing tool costs. A comfortably user-friendly program has been developed for the calculation and evaluation of the grinding costs. After the input of data e.g. the table feed speed, costs of the grinding wheels etc. this program is able to calculate the production costs per work-piece and it is able to compare the grinding costs of different grinding procedures.

Key Issues of the Work: • Economical profile grinding • CD Grinding • Comparison of grinding costs Status: On-going Publications of this work: 1. Hoffmeister, H.-W.: Hohe Zerspanungsleistungen durch Schleifen mit CD – sichere,

werkstoffangepaßte und wirtschaftliche Prozeßführung, Dissertation, TU-Braunschweig, 1995

2. Hoffmeister, H.-W.; Michel, S.: Efficient CD Grinding, 4th International Machining & Grinding Conference, Troy, Michigan, USA, 2001

3. Hoffmeister, H.-W; Illenseer, S.: Wirtschaftliches Profilschleifen durch Continuous Dressing, Manufacturing conference, Poznan, Poland 2001

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G56 CVD-Microgrinding Tools Contact Information: Dr.-Ing. Hans-Werner Hoffmeister Institute of Machine Tools and Production Technology Technical University Braunschweig Germany Tel: +49 531 391 7606 Fax: +49 531 391 5842 Email: [email protected] http: www.iwf.ing.tu-bs.de Abstract: Our experimental studies have shown that microstructuring of hard and brittle materials can be done by microgrinding with CVD-diamond coated micro abrasive pencils. The layer of this tools is characterised by a close arrangement of diamonds with more sharp cutting edges but on the other hand less chip volume in comparison to electro-plated tools. CVD-diamond tools can be realised with diameters smaller than 0.1 mm. These tools can be used for internal circular grinding and honing of hard and brittle materials. Although they have an abrasive diamond layer it is possible to process large amounts of hardened steel. This tools enable to produce three dimensional microstructures with a smooth surface and minimal edge chipping.

Key Issues of the Work: • Grinding of microstructures with CVD-Micrpgrinding tools Status: On-going Publications of this work: 1. Hoffmeister, H.-W.; Menze, B.: Grinding and Honing Micro Bores in Hardened Steel with

CVD-Diamond Pencils. In: Proceedings of the euspen International Conference, Glasgow, Scottland, May 31st - June 3rd, 2004, pp.

2. Hoffmeister, H.-W. ; Wenda, A.: Precision manufacturing of micro moulding tools of glass and sintered carbide. In: Proceedings of the 10th International Conference on Precision Engineering (ICPE), Japan Society for Precision Engineering JSPE, July 18th/20th 2001, Pacifico Yokohama, Japan, (to be published)

3. Hoffmeister, H.-W. ; Wenda, A.: Novel grinding tools for machining precision micro parts of hard and brittle materials. In: Proceedings of the 15th annual meeting of the ASPE, October 22th/27th 2000, Scottsdale, Arizona, USA, pp. 152-155

4. Hoffmeister, H.-W. ; Wenda, A.: 3D micromachining of single crystal silicon. In: EUSPEN (Proceedings of the 1st international conference and general meeting of the european society for precision engineering and nanotechnology), Bremen, May 31th - June 4th 1999, pp. 396-400

5. Gäbler, J. ; Schäfer, L. , Wenda, A. ; Hoffmeister, H.-W.: Developement and application of CVD diamond micro tools for milling and grinding. In: EUSPEN (Proceedings of the 1st international conference and general meeting of the european society for precision engineering and nanotechnology), Bremen, May 31th - June 4th 1999, pp. 434-438

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G57 Film Finishing of Ceramics

Contact Information: Dr.-Ing. Hans-Werner Hoffmeister Institute of Machine Tools and Production Technology Technical University Braunschweig Germany Tel: +49 531 391 7606 Fax: +49 531 391 5842 Email: [email protected] http: www.iwf.ing.tu-bs.de Abstract: The finishing of technical ceramics is still relatively time-consuming and expensive, which is a basic reason why a broader application of this material group is still restricted despite its high technological potential. The finding of appropriate production techniques for the economic precision machining of technical ceramics is therefore of great interest. In search of both, a nearly damage-free and economic external cylindrical machining procedure of ceramic materials, at the Institute of Machine Tools and Production Technology film finishing is examined with regard to its achievable surface quality as well as its attainable stock removal rate. The examined ceramics are silicon carbide, silicon nitride and zirconium oxide. All used finishing band grain sizes showed almost linear stock removal rate processes as a result of the uninterrupted band infeed, whereby new cutting grain was steadily conveyed into the contact zone. Of all the tested ceramics, the highest material removal rates could be achieved with the machining of silicon carbide which can be ascribed to the high brittleness of this material. The roughness of the ceramics, in dependency of the finishing band grain size, could rapidly be set to a low level. On continuing the film finishing process, the roughness was nearly stationary. Key Issues of the Work: • Film Finishing of ceramics with diamond finishing belts • Tribological tests for the determination of the functional properties of external cylindrical

machined ceramics Status: In progress Publications of this work: 1. Hoffmeister, H.-W. ; Kreis, R.: Bandfinishen von Keramik – Eine Alternative zum Honen?

In: IDR 33, Nr.1, 1999, pp. 42-48

2. Hoffmeister, Hans-Werner ; Herrmann, Hartwig: Feinbearbeitung und Verschleißprüfung technischer Keramiken. In: Tribologie und Schmierungstechnik, Heft 1/2002, 2002, pp. 9-11

3. Hoffmeister, Hans-Werner; Herrmann, Hartwig: Feinbearbeitung technischer Keramiken mittels Bandfinishing. In: Jahrbuch Schleifen, Honen, Läppen und Polieren. 61. Ausgabe, 2004, pp. 302-312

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G58 Fine Grinding with Foil Tools Contact Information: Dr.-Ing. Hans-Werner Hoffmeister Institute of Machine Tools and Production Technology Technical University Braunschweig Germany Tel: +49 531 391 7606 Fax: +49 531 391 5842 Email: [email protected] http: www.iwf.ing.tu-bs.de Abstract: Face machining with lapping kinematics is a manufacturing process normally used for the production of high surface qualities. The demands on shape accuracy and surface roughness can normally be achieved with these process kinematics. The production of high surface qualities involves a multistage process. The macro-geometry is produced by lapping and the micro-geometry by polishing. During polishing the final quality is produced and sub-surface damages have to be removed. Therefore, the machining time is rather long. Furthermore, the workpiece must be thoroughly cleaned in order to remove any abrasive particles which may still adhere to the surface. The disposal costs of the used abrasive suspension is high. We used foil tools with diamond grits for the manufacturing of brittle and hard materials to achieve the same results as when using the conventional technology. These foil tools consist of plastic foils which are coated with abrasive grits on the upper side and which can be secured to carrier discs on conventional polishing machines by a self-adhesive layer on the underside. These foil tools are the result of a continual improvement of finishing belts used for super-finishing. This technology allows a separation of that tool part which is responsible for the surface roughness and the part which is responsible for the shape accuracy. The shape accuracy is achieved by the carrier disc and the surface roughness is produced by the foil tool. The carrier disc did not wear during the lapping process, hence no dressing is necessary. Key Issues of the Work: • Design and prototyping of a test rig with lapping kinematics and controlled foil tool infeed • Fine grinding of brittle and hard materials Status: In progress Publications of this work: 1. Hoffmeister, H.-W. ; Gäbler, J.: Feinschleifen von Keramik mit Folienwerkzeugen. In:

Industrie Diamanten Rundschau (IDR) 31 (1997) 3, pp. 228-23

2. Hoffmeister, Hans-Werner; Michel, Stephan; Herrmann, Hartwig: Feinschleifen optischer Gläser mit Diamant-Folienwerkzeugen. In: IDR-Industrie Diamanten Rundschau , Ausgabe Nr.3, 2000, pp. 202-209

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3. Hoffmeister, Hans-Werner; Herrmann, Hartwig: Fine Grinding of Optical Glasses with Diamond Foil Tools. In: Proceedings of the 2nd International euspen Conference, Volume 2, Turin, Italy, 2001, pp. 840-843

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G59 Grinding with Cryogenics Contact Information: Dr.-Ing. Hans-Werner Hoffmeister Institute of Machine Tools and Production Technology Technical University Braunschweig Germany Tel: +49 531 391 7606 Fax: +49 531 391 5842 Email: [email protected] http: www.iwf.ing.tu-bs.de Abstract: From the economic and ecological point of view it is beneficial to reduce the coolant quantities or to completely manage without coolants. An approach in grinding is to use liquid nitrogen as coolant. Replacing the coolants or reducing the coolant quantities used during grinding, however, is only possible when the exact thermophysical processes are known. the effect of liquid nitrogen on the temperature distribution in the workpiece was proved. Furthermore, a comparison is made with the use conventional cooling in grinding. As a result, it was possible to prove the cooling effect of liquid nitrogen which was connected with a clear decrease in the maximum temperature in the contact zone. The test results show that the use of liquid nitrogen as coolant may be an alternative to conventional cooling lubrication. Key Issues of the Work: • • •

Cryogenic cooling Grinding temperature Production process

Status: On-going Publications of this work: 1. Hoffmeister, H.-W.; Hesselbach, J.; Maiz, K.; Machanova, I.: Surface Grinding with

Cryogenics, WGP Annals of the German Academic Society of Production Engineering, Volume XI, issue 2, 2004

2. Hoffmeister, H.-W.; Maiz, K.: Trockenschleifen mit Hilfe der Cryotechnik, 5. Seminar Moderne Schleiftechnologie, 13. Mai 2004

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G60 Microgrinding Contact Information: Dr.-Ing. Hans-Werner Hoffmeister Institute of Machine Tools and Production Technology Technical University Braunschweig Germany Tel: +49 531 391 7606 Fax: +49 531 391 5842 Email: [email protected] http: www.iwf.ing.tu-bs.de Abstract: The Institute of Machine Tools and Production Technology of the Technical Univeristy Braunschweig has many years of expert knowlegde on the field of microgrinding. The technology of microgrinding allows to manufacture fast and flexible microstructures and micro parts in hard and brittle materials. The large range of commercial diamond dicing blades enable many-sided structure possibilities. Even hardened steels can be machined by this production technology. The precondition for microgrinding hardened steel is the use of boron nitride (CBN) as abrasive. By microgrinding smallest structures with a high accuracy and a very high surface quality can be produced. At present an aspect ratio up to 40:1 can be realised. The minimum dimension of these structures are presently about 5-20 µm, depending of the machined workpiece material.

Key Issues of the Work: • Grinding of microstructures with diamond and CBN tools Status: On-going Publications of this work: 1. Hoffmeister, H.-W.; Hlavac, M.: Dressing of Micro-Grinding Wheels, Proceedings of the

Euspen Int. Conference, Glasgow, Scottland, May 31st - June 3rd, 2004, pp. 135-136 2. Hoffmeister, H.-W.; Hlavac, M.: Measurement and Simulation of Heat Development during

the Micro-Grinding Process of Hardened Steels. In: Proceedings of the euspen International Conference, Glasgow, Scottland, May 31st - June 3rd, 2004, pp. 344-345

3. Hoffmeister, H.-W.; Hlavac, M.: Grinding of Microstructures in Hardened Steel with CBN Tools. In: Proceedings of the euspen International Topical Conference, Aachen, Germany, May 19th/20th, 2003, pp. 337-340

4. Hoffmeister, H.-W.; Hlavac, M.: Grinding of Microstructures in Hardened Steel with CBN Tools. In: Proceedings of the 17th annual meeting of the ASPE, St. Louis, USA, October 20th - 25th, 2002, pp. 490-494

5. Hoffmeister, H.-W.; Hlavac, M.: Schleifen von Mikrostrukturen. Tagungsband des 10. Feinbearbeitungskolloquiums in Braunschweig, Vulkan Verlag, Essen, 2002, pp. 7.1-7.24

6. Hoffmeister, H.-W.; Wenda, A.: Mikrofertigung-Fräsen, Bohren und Schleifen im Mikrobereich. In: Lösungen aus Forschung und Industrie, 9. Internationales Braunschweiger FBK, Vulkan-Verlag, Oktober 12th/14th, 1999, pp. 18.1-18.20

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7. Hoffmeister, H.-W.; Wenda, A.: Investigation into the Microgrinding Technique for the Production of Microstructures in Silicon and Glass. In: Micro System Technologies 98 (Proceedings of the 6th International Conference on Micro Electro, Opto, Mechanical Systems and Components), Potsdam, Germany, December 1st/3rd 1998, pp. 433-438

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G61 Simulation of Grinding Process with FEM Contact Information: Dr.-Ing. Hans-Werner Hoffmeister Institute of Machine Tools and Production Technology Technical University Braunschweig Germany Tel: +49 531 391 7606 Fax: +49 531 391 5842 Email: [email protected] http: www.iwf.ing.tu-bs.de Abstract: Increased quality requirements, as well as high safety and low production cost are the demands on modern efficient grinding methods. In order to fulfill these aims, an exact knowledge of the grinding process is necessary. For this purpose the grinding process was simulated on the basis of the Finite Element Method (FEM). For the simulation, a FEM model based on Jaeger´s concept was developed. The shape deviation of the workpiece which occurs during the grinding operation can be calculated with this model. Also this FEM-Simulation enables to determine the part of the energy which dissipates as heat into the workpiece. By means of the FEM-Simulation the temperature field distribution inside the workpiece can be calculated considering the machine setting parameters und the properties of the material. This simulation of the grinding process enhances not only the process understanding by visualizing, but also serves as a means of the process design.

Key Issues of the Work: • Process simulation • Temperature distribution • FEM-Simulation Status: On-going Publications of this work: 1. Hoffmeister, H.-W.; Weber, T. : Simulation of Grinding by Means of the Finite Element

Analysis, 3rd International Machining & Grinding Conference, 4.-7.10. 1999, Society of Manufacturing Engineers Cincinnati, Ohio, USA, 1999

2. Hoffmeister, H.-W., Weber Th.: Wärmephysikalische Vorgänge und ihre Simulation beim Schleifen, Jahrbuch Schleifen, Honen, Läppen und Polieren, 58. Ausgabe, Vulkan-Verlag, 1997

3. Weber Th.: Simulation des Flachprofilschleifens mit Hilfe der Finite-Elemente-Methode, Dissertation TU Braunschweig, 2001

4. Hoffmeister, H.-W., Weber Th.: Simulation of Grinding by Means of the Finite Element Analysis. Abrasives Magazine, USA, Februar/März 2000,

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G62 Flexible Crankshaft Grinding Contact Information: Professor Berend Denkena Institute of Production Engineering and Machine Tools Hannover University Schoenebecker Allee 2 30823 Garbsen Germany Tel: +49 511 762 2533 Fax: +49 511 762 5115 Email: [email protected] http:/www.ifw.uni-hannover.de Abstract: Crankshafts for combustion engines are geometrically complex parts. The design of the grinding process at the end of the production chain is of major importance to the part quality and is targeted by this thesis. Attention is paid to the special features of crankshafts: due to the different axes of rotation the modeling and technology of continuous path controlled grinding is analyzed. The grinding mode is characterized by a eccentrically rotating crankpin. A further special feature are crankshaft shoulders, whose machining is identified by large contact areas. The conventional process strategy with radial tool infeed is compared to machining with infeed in axial direction. The latter results in an improved surface integrity of the workpiece. Furthermore, a concept for the layout of multi-stage processes is designed and verified for crankshaft relevant workpiece materials, namely nodular cast iron in a pearlitic matrix, austempered ductile iron (ADI) and microalloyed steel. Key Issues of the Work: • Flexible Crankshaft Grinding, Process Strategy Status: completed 2004 Publications of this work: 1. Friemuth, T.; Becker, J. C.: High Speed Grinding of Crankshafts in One Set-Up. In:

Proceedings of the IGT Annual Seminar, "Advances in Grinding Technology", University of Bristol, 05.03.2002

2. Tönshoff, H. K.; Friemth, T.; Becker, J. C.: Continuous path controlled grinding of crankshafts. In: Abrasive Magazine, Edition 12/01, pp. 25-29, 2000

3. Tönshoff, H. K.; Denkena, B.; Becker, J. C.: Prozesskettengestaltung beim Schleifen von Kurbelwellen. In: "Marktchance Individualisierung", Hrsg. Reinhart, G., Zäh, M..F., Springer Verlag, ISBN 3-540-00594-3, 2003

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G63 Influence of the Grinding Process on Surface Near Residual Stress Contact Information: Professor Berend Denkena Institute of Production Engineering and Machine Tools Hannover University Schoenebecker Allee 2 30823 Garbsen Germany Tel: +49 511 762 2533 Fax: +49 511 762 5115 Email: [email protected] http:/www.ifw.uni-hannover.de Abstract: This research is focused on surface near residual stress states of cemented carbide tools after the grinding process. Special attention is given to pre-coating treatment processes. Methods applied are the X-ray techniques sin2ψ and scattering vector. Key Issues of the Work: • Different grinding processes create different residual stress states • PVD coatings reduces compressive stress in the substrate • Depth reduced stress information depends on surface quality as result of grinding process Status: Until 2006 at least Publications of this work: 1. B. Denkena, T. Friemuth, B. Breidenstein, C. Spengler: Einfluss unterschiedlicher

Schleifverfahren auf die Randzoneneigenschaften bei der Herstellung von Hartmetallwerkzeugen, Diamond Business, 6, 3, pp. 50-56 (2003)

2. B. Denkena, T. Friemuth, B. Breidenstein, C. Spengler: Einfluss der Prozessauslegung unterschiedlicher Schleifverfahren zur Herstellung von Hartmetallwerkzeugen auf den Eigenspannungszustand der Randzone, Jahrbuch Schleifen, Honen, Läppen und Polieren, 61. Ausgabe, pp. 78-88, Vulkan-Verlag Essen (2004)

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G64 Crushing for Vitreous Bonded Diamond Grinding Wheels Contact Information: Professor Berend Denkena Institute of Production Engineering and Machine Tools Hannover University Schoenebecker Allee 2 30823 Garbsen Germany Tel: +49 511 762 2533 Fax: +49 511 762 5115 Email: [email protected] http:/www.ifw.uni-hannover.de Abstract: In the tool manufacturing industry hard materials like cemented carbides are commonly used, so that diamond wheels are mostly indispensable for the grinding processes. In most applications the grinding tools have to be profiled. CNC crushing is particularly suitable for dressing diamond grinding tools. The grinding wheel profile is generated by the CNC-system of the machine tool through the combined movement of its axes. Therefore it is independent of the dressing roller shape, evoking a high process flexibility. The dressing speed is continuously controlled by means of a closed loop system. Thus no relative speed occurs between the tool and the grinding wheel. This contributes substantially to reduce the dressing roller wear. Anyway the grinding wheel bonding system has to be sufficiently brittle, so that grits and bond material can be pulled out by the dressing normal forces which arise at the contact point. Key Issues of the Work: • Minimizing of tool geometry Status: still running Publications of this work: 1. Denkena, B., Becker, J.C., Catoni, F., 2004, FEM-Simulation of CNC Crushing for Vitreous

Bonded Diamond Grinding Wheels, ISAAT 2004, Paper 62 2. Hessel, D., 2003, Punktcrushieren keramisch gebundener Diamantschleifscheiben, Dr.-Ing.,

Dissertation, University of Hannover, Germany. 3. Denkena, B., Becker, J.C., Catoni, F., 2003, Characterization of Vitreous Bonded Grinding

Wheels for CNC Crushing, Key Engineering Materials, Vol. 257-258, Advances in Abrasive Technology VI, 303-308.

4. Tönshoff, H.K., Denkena, B., Hessel, D., Brandes, A., 2002, Flexible and Fully Automated Intelligent Grinding System, 35th CIRP International Seminar on Manufacturing Systems, Seoul, South Korea, 555-560

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G65 Electro-Contact Discharge Dressing – Potential of Truing and Dressing Super Abrasive Grinding Wheels Contact Information: Professor Berend Denkena Institute of Production Engineering and Machine Tools Hannover University Schoenebecker Allee 2 30823 Garbsen Germany Tel: +49 511 762 2533 Fax: +49 511 762 5115 Email: [email protected] http:/www.ifw.uni-hannover.de Abstract: The super abrasives cubic crystalline boron nitride (CBN) and diamond have great potentials in grinding applications, because of their exalted wear resistance. For example in machining difficult-to-machine steel, tungsten carbide or ceramic materials, the use of super abrasives is necessary. First of all combined with a metallic bonding system a significant increased removal rate can be realized. Such grinding wheels are characterized by high grain retention forces and good profile accuracy, additionally they enable to bond the grits with a high grain protrusion. It must be considered that technological and economical advantages of metal-bonded super abrasive grinding wheels can only be achieved by convenient conditioning methods. Conventional abrasive dressing methods with the separation in the two single processes truing and dressing cause long conditioning-times and high wear rates of the conditioning-tools. One solution to this problem is the use of the technique electro contact discharge dressing (ECDD). The principle of this technology depends on electro-thermal bonding-removal which ensures an adequate grain protrusion of the grinding layer. The work describes the potential of this dressing method. Besides generating a high grain protrusion it is also possible to provide the desired tool profile in one working process. Key Issues of the Work: • metal bonded grinding wheels, single-electrode setup, dressing, profile generation Status: in process Publications of this work: 1. Denkena, B.; Becker, J. C.; van der Meer, M.: Electro Contact Discharge Dressing - Potential

of truing and sharpening super abrasive grinding wheels. In: 6th International Symposium on Advances in Abrasive Technology (ISAAT 2003), 18-20 November 2003, University of Bristol, UK, 2003

2. Denkena, B.; Becker, J. C.; Reichstein, M.; van der Meer, M.: Kontakterosives Konditionieren. Jahrbuchs Schleifen, Honen, Läppen und Polieren (61. Ausgabe) , Vulkan Verlag, 2004

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G66 Eco-Efficient Grinding Processes Contact Information: Professor Berend Denkena Institute of Production Engineering and Machine Tools Hannover University Schoenebecker Allee 2 30823 Garbsen Germany Tel: +49 511 762 2533 Fax: +49 511 762 5115 Email: [email protected] http:/www.ifw.uni-hannover.de Abstract: While looking at machining processes, not only classical process outputs like costs, machining time and achieved quality are important but ecological aspects are more and more focused on. Especially finishing processes like grinding consume, compared to turning for example, a higher amount of energy, if power consumption is plotted against material removal rate. Some approaches to set up an energy-efficient and environmentally friendly grinding process are • an improved manufacturing process design • changes of the machine tool, especially regarding the design of the coolant supply unit, incl.

the nozzles as well as filtering and pump devices but also the grinding wheel itself. • changes of process parameters, which can also significantly improve the power consumption

per part. Especially an improved process monitoring by use of Acoustic Emission signals allows a modified, adapted process set-up, culminating in shorter machining time and therefore costs, potentially improved part quality and less coolant need.

Altogether, these measures allow an adapted, eco-efficient grinding process design, capable of significantly reducing energy consumption and coolant supply need. Key Issues of the Work: • Improved Eco-Efficiency of Finish-Grinding-Operations Status: still running Publications of this work: 1. Denkena, B.; Reichstein, M.; Jacobsen, J., Jung, M., Kramer, N.: Eco- and Energy-Efficient

Processes. International Symposium on Advanced Abrasive Technology, St. Petersburg, Russia, 2005.

2. Kramer, N.: Development of Low Energy and Ecoefficient Grinding Technologies. Ufordat Database of the Federal Environmental Agency, Germany, 2004. http://doku.uba.de

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G67 Form Crushing of Vitreous Bonded Grinding Wheels for High Precision Grinding Contact Information: Professor Berend Denkena Institute of Production Engineering and Machine Tools Hannover University Schoenebecker Allee 2 30823 Garbsen Germany Tel: +49 511 762 2533 Fax: +49 511 762 5115 Email: [email protected] http:/www.ifw.uni-hannover.de Abstract: In the tool manufacturing industry hard materials like cemented carbides are commonly used, so that diamond wheels are mostly indispensable for the grinding processes. In most applications the grinding tools have to be profiled. CNC crushing is particularly suitable for dressing diamond grinding tools. The grinding wheel profile is generated by the CNC-system of the machine tool through the combined movement of its axes. Therefore it is independent of the dressing roller shape, evoking a high process flexibility. The dressing speed is continuously controlled by means of a closed loop system. Thus no relative speed occurs between the tool and the grinding wheel. This contributes substantially to reduce the dressing roller wear. Anyway the grinding wheel bonding system has to be sufficiently brittle, so that grits and bond material can be pulled out by the dressing normal forces which arise at the contact point. Key Issues of the Work: • Combining the advantages of CBN and dressable tools Status: still running Publications of this work: 1. Denkena, B.; Becker, J.C.; Catoni, F.: FEM-Simulation of CNC Crushing for Vitreous

Bonded Diamond Grinding Wheels. Proceedings of the 7th International Symposium on Advances in Abrasive Technology, Bursa (Turkey), June 17-19, 2004

2. Denkena, B.; Becker, J.C.; Catoni, F.: Characterization of Vitreous Bonded Grinding Wheels for CNC. Proceedings of the 6th International Symposium on Advances in Abrasive Technology, Bristol (UK), November 18-20, 2003

3. Hessel, D.; Dennis, P.; Völz, D.: Profilschleifen mit punktcrushierbaren Diamant- und CBN-Schleifscheiben. In: 4. Seminar "Moderne Schleiftechnologie und Feinstbearbeitung", Neue Entwicklungen und Trends aus Forschung und Praxis, 25.04.2002, Villingen-Schwenningen (D), p. 10-1-10-15

4. Tönshoff, H.K.; Friemuth, T.; Hessel, D.: Crushing Process for Vitreous Bonded CBN and Diamond Grinding Wheels. In: Annals of the German Academic Society for Production Engineering (WGP) 2001. p. 13-16

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G68 Manufacturing of Micro Functional Surface Structures by Grinding Contact Information: Professor Berend Denkena Institute of Production Engineering and Machine Tools Hannover University Schoenebecker Allee 2 30823 Garbsen Germany Tel: +49 511 762 2533 Fax: +49 511 762 5115 Email: [email protected] http:/www.ifw.uni-hannover.de Abstract: Micro functional structures on part surface are required in many fields of manufacturing processes, for example riblet-structures can reduce the turbulence drag on the surface of turbine blades up to 10%. One possibility to manufacture this defined micro geometry is the application of grinding, which is supposed to be the most efficient and suitable way in comparison with other cutting processes. Traditional grinding processes are mostly carried out to achieve possibly smooth surface. By using specified grinding wheels and process kinematics this defined micro structure can be achieved. Key Issues of the Work: • Micro functional structures by Grinding Status: still running Publications of this work: 1. Tönshoff, H.K.; Denkena, B.; Friemuth, T.; Reichstein, M.: Precision grinding of

components for aerostatic micro guidance. In: Precision Engineering 27/2003, pp. 185-188 2. Denkena, B; Friemuth, T.; Reichstein M.: Potentials of Different Process Kinematics in

Micro Grinding. In: Annals of the CIRP, 52/1, pp.463-466, 20

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G69 Process Development in Grinding of Ceramic Steel Compounds Contact Information: Professor Berend Denkena Institute of Production Engineering and Machine Tools Hannover University Schoenebecker Allee 2 30823 Garbsen Germany Tel: +49 511 762 2533 Fax: +49 511 762 5115 Email: [email protected] http:/www.ifw.uni-hannover.de Abstract: Ceramic steel compounds show high potential in improvement of the wear resistance of forging dies. Different material properties of these compounds lead to new demands on the machining process. On one hand the high hardness of ceramic leads to brittle material removal, while on the other hand the material removal of steel is characterized by chip formation and plastic deformation. This provokes fundamentally different wear mechanisms of the grinding tool. Although it has been already shown in principle that it is possible to machine these materials with diamond grinding tools, until now there is no economical grinding process available. In order to extend the knowledge about the wear mechanisms of the grinding tools, investigations have been carried out by varying the process parameters as well as the bonding specifications. Based on the achieved results a sufficient process design can be offered. Key Issues of the Work: • Production Process • Grinding • Ceramic Steel Compound Status: in progress Publications of this work: 1. Tönshoff, H.K.; Denkena, B.; Friemuth, T.; Glatzel, T.; Stahl, M.: Grinding of a Ceramic

Steel Compound. Annals of the German Academic Society for Production Engineering (WGP), Vol. (2003), pp. 1-4

2. Tönshoff, H.K.; Denkena, B.; Friemuth, T.; Glatzel, T.; Stahl, M.: Ceramics and Steel - Two Different Materials - One Grinding Process? In: Materials Week 2002, European Congress on Advanced Materials, their Processes and Applications, International Congress Centre Munich, 30 Sep - 2 Oct 2002

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G70 Hard-fine Machining of Gears and Crankshafts Contact Information: Professor Berend Denkena Institute of Production Engineering and Machine Tools Hannover University Schoenebecker Allee 2 30823 Garbsen, Germany Tel: +49 511 762 2533 Fax: +49 511 762 5115 Email: [email protected] http:/www.ifw.uni-hannover.de Abstract: The current developments in gear manufacturing are characterized by making even higher demands on load capacity, quiet running and life time of the gears. At the same time the workpiece dimensions as well as the production costs have to be constantly reduced. This leads to an enhancement of the gear quality aimed at increasing the load capacity and minimizing the running noises. After cutting the gear profile by means of hobbing or shaving, a heat treatment of the workpiece is carried out with the target of increasing the wear resistance of the tooth flanks. A hard fine machining is inevitable in order to remove the material distortions which come into existence during the heat treatment and to fulfil the dimensional and quality requirements. Among the existing processes for hard fine machining of gears, generating grinding by means of cylindrical grinding worms shows the highest potential in batch production because of the high material removal performance that can be reached. Hereby the process potentials as well as models for calculating the specific material removal rate along the tooth flanks in dependence of different process parameters are considered. Key Issues of the Work: • Improving the performance of gear and crankshaft grinding Status: still running Publications of this work: 1. Denkena, B.; Becker, J.C.; Jung, M.; Catoni, F.: Optimization of the Cooling Conditions in

Continuous Generating Grinding of Gears. Proceedings of the 7th International Symposium on Advances in Abrasive Technology, Bursa (Turkey), June 17-19, 2004

2. Denkena, B.; Becker, J.C.; Catoni, F.; Türich, A.: Kontinuierliches Wälzschleifen von Verzahnungen. In: Jahrbuch Schleifen, Honen, Läppen und Polieren, 61(2004), p. 65-77

3. Denkena, B.; Becker, J.C.; Catoni, F.: Hard Fine Machining of Gears through Continuous Generating Grinding. Proceedings of the 6th International Symposium on Advances in Abrasive Technology, Bristol (UK), November 18-20, 2003

4. Friemuth, T.; Becker, J.C.: High Speed Grinding of Crankshafts in One Set-Up: Proc. of IGT Annual Seminar, "Adv. in Grinding Technology", Univ. of Bristol, 05.03.2002. p. 1-12

5. Tönshoff, H.K.; Hillmann-Apmann, H.; Marzenell, C.: Wear Behaviour of Electroplated Diamond Tools in Gear Honing. Diamante Applicazioni & Technologia, 27(2001), p. 94-99

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6. Tönshoff, H.K.; Friemuth, T.; Becker, J.C.: Next Generation of Crankshaft Production. In: Proceedings of 1st International Seminar on Progress in Innovative Manufacturing Engineering, PRIME 2001, 20-22 June 2001, Sestri Levante (Italy). p. 177-180

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G71 In-Process Monitoring by Acoustic Emission Contact Information: Professor Berend Denkena Institute of Production Engineering and Machine Tools Hannover University Schoenebecker Allee 2 30823 Garbsen Germany Tel: +49 511 762 2533 Fax: +49 511 762 5115 Email: [email protected] http:/www.ifw.uni-hannover.de Abstract: Acoustic Emission technology is well known in grinding processes and gap control monitoring devices are commonly used. Nevertheless, the quantitative signal level is rarely taken into consideration for monitoring devices, although very good correlations are found between this level and certain process states. Acoustic Emission signals can be used to monitor dressing parameters and conditions as infeed and grinding wheel geometry but also indicate unstable process conditions in plunge grinding due to roundness errors. Since the signal level correlates with the residual stress state of the part’s subsurface integrity, acoustic emission technology enables to evaluate adapted process parameters for grinding burn free processes and the qualitative comparison of different coolant supply conditions. Key Issues of the Work: • In-Process Monitoring Status: still running Publications of this work: 1. Denkena, B.; Jacobsen, J.; Kramer, N.: Dressing Monitoring by Acoustic Emission.

International Symposium on Advanced Abrasive Technology, St. Petersburg, Russia, 2005. 2. Denkena, B.; Reichstein, M.; Jacobsen, J., Jung, M., Kramer, N.: Eco- and Energy-Efficient

Processes. International Symposium on Advanced Abrasive Technology, St. Petersburg, Russia, 2005.

3. Tönshoff, H.K.; Friemuth, T.; Becker, J.C.: Process Monitoring in Grinding. Annals of the CIRP, Vol. 51/2, pp. 551-571, 2002.

4. Tönshoff, H.K.; Jung, M.; Männel, S.; Rietz, W.: Using Acoustic Emission Signals for Monitoring of Production Processes. Ultrasonics, Vol. 37, pp. 681-686, 2000.

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G72 Production of Complex Medical Implants with Ceramic Functional Surfaces Contact Information: Professor Berend Denkena Institute of Production Engineering and Machine Tools Hannover University Schoenebecker Allee 2 30823 Garbsen Germany Tel: +49 511 762 2533 Fax: +49 511 762 5115 Email: [email protected] http:/www.ifw.uni-hannover.de Abstract: Permanent implants like knee joint replacements are applied in areas where the body’s rebuilding of the diseased or injured structures is impossible. In such cases the orthopedist avails itself of technical solutions in the form of prostheses, which substitute the natural joint - all or part. At the Institute of Production Engineering and Machine Tools (IFW) the development of automated working on the free form surface of low-wear ceramic implants considering knee joints as example is promoted under medical and technical points of view with the aim of optimized lifetime. The basic mechanisms of five-axis grinding and polishing are analyzed and based on this process and tool design, and development of suitable manufacturing strategies take place. This technology will enable the fabrication of variegated kinds of complex prostheses for medical technology, for example for wrists or ankles. The known superiority of hip joint replacements will be made accessible for patients, which are in need of complex shaped implants. Key Issues of the Work: • Free form surface • Five-axis manufacturing • Ceramic Status: in process Publications of this work: 1. Denkena, B.; Becker, J. C.; van der Meer, M.: Fertigung zukunftsfähiger Implantate –

Automatisierte Freiformflächenbearbeitung verschleißarmer Keramikimplantate am Beispiel Kniegelenk. wt Werkstattstechnik online 2004_06, Jahrgang 94, S. 284-288, Springer-VDI-Verlag, Düsseldorf, 2004

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G73 Influence of Different Manufacturing Steps on Characteristics of Coated Carbide Tools Contact Information: Professor Berend Denkena Institute of Production Engineering and Machine Tools Hannover University Schoenebecker Allee 2 30823 Garbsen Germany Tel: +49 511 762 2533 Fax: +49 511 762 5115 Email: [email protected] http:/www.ifw.uni-hannover.de Abstract: In dry cutting with coated carbide tools the quality of the layer composite has a significant influence on tool life. Because of thermal and mechanical loads in tool use adhesion failures may occur, which is substantially affected by surface and subsurface characteristics of the substrate, already developed during the tool grinding process. The grinding process may induce compressive and tensile residual stress in the subsurface of the substrate as a result of mechanical and thermal effects. By variation of grinding process parameters, e.g. abrasive grain size and feed rates, mechanical and thermal effects are affected, which leads to the formation of residual stress in the subsurface. Layer adhesion is affected by the residual stress state in the subsurface. In this work the influence of micro blasting was examined for subsurface conditions. The ground and microblasted samples are coated with TiN in a PVD process. After coating the residual stress in the subsurface of the substrate is measured again. Key Issues of the Work: • Carbide Tools • Grinding • Residual Stress Status: Completed 2003 Publications of this work: 1. Denkena, B.; Friemuth, T.; Spengler, C.: Modelling and Process Design for Different

Grinding Operations of Carbide Tools, Annals of the German Academic Society for Production Engeneering, WGP X, 2003, S. 15-18

2. Denkena, B.; Friemuth, T.; Breidenstein, B.; Spengler, C.: Einfluss unterschiedlicher Schelifverfahren auf die Randzoneneigenschaften bei der Herstellung von Hartmetallwerkzeugen, Diamond Buisiness, Ausgabe 5, 2003, S. 50-56

3. Tönshoff, H.K.; Denkena, B.; Friemuth, T; Spengler, C.: Influence of Different Grinding Processes on Coating Adhesion on Cutting Tools, 3rd International Conference The Coatings in Manufacturing Engineering, November 28-29, 2002, Thessaloniki, Greece

307

G74 Ultrasonic Grinding Contact Information: Professor Berend Denkena Institute of Production Engineering and Machine Tools Hannover University Schoenebecker Allee 2 30823 Garbsen Germany Tel: +49 511 762 2533 Fax: +49 511 762 5115 Email: [email protected] http:/www.ifw.uni-hannover.de Abstract: Investigations in peripheral and face grinding pointed to specific characteristics of these processes. Based on these results improvements for highest surface quality and the reduction of thermal loads are developed. One possibility to minimize the influence of the micro geometry of the grinding tool is the application of ultra-sonic grinding. By using an ultra precision machine tool and fine grained grinding wheels high surface qualities can be achieved. Key Issues of the Work: • Minimizing of tool geometry Status: still running Publications of this work: 1. Denkena, B.; Hoffmeister, H.-W.; Reichstein, M.; Illenseer, S.: Mikrozerspanung.

Kolloquium Mikroproduktion, Eine Kooperation der Sonderforschungsbereiche 440, 499 und 516, S. 65-74, 2003

2. Tönshoff, H.K.; Denkena, B.; Friemuth, T.; Reichstein, M.: Precision grinding of components for aerostatic micro guidance. In: Precision Engineering 27/2003, pp. 185-188

3. Denkena, B; Friemuth, T.; Reichstein M.: Potentials of Different Process Kinematics in Micro Grinding. In: Annals of the CIRP, 52/1, pp.463-466, 2003

4. Denkena, B.; Hoffmeister, H.-W.; Reichstein, M.; Illenseer, S.: Process Development in Machining of Micro Guideways. Micro Systems Technology (MST), 2004

308

G75 New Tool System, T-Tool and T-Tool Profile Contact Information: Professor Dr. Ing. Taghi Tawakoli Faculty of Mechanical Engineering University of Applied Science Furtwangen Jakob-Kienzle Str. 17 78054 VS-Schwenningen Germany Tel: +49-7720-307-4380 Fax: +49-7720-307-4208 Email: [email protected] Abstract: T-tool and T-Tool Proile are two new innovative , multi functional tool systems with super abrasive grit material. By using both T-Tool, the grinding process is cooled down considerably and less grinding power is needed. The tool wear is far less than conventional tool with the same material removal. So far by T-Tool Profile even with tool wear , there is no deviation from the defined profile of the workpiece. This is due to special design of the T-Tool Profile Key Issues of the Work: • Less tool wear, better cooling and lubrication using T-Tools • Less grinding power, better surface quality and more efficiency in process using both T-tools • Exact tolerances and geometry using T-Tool Profile Status: Completed Publications of this work: 1. Innovative Werkzeugsysteme zum Schleifen, Abrichten und Fräsen (T-Tool Profil, und T-

Tool), III. Seminar „Moderne Schleiftechnologie“, an der FH-Furtwangen, Neue Tonhalle Villingen, 13. April 2000

2. Innovative Werkzeugsysteme zum Schleifen, Abrichten und Fräsen, Metallbearbeitung Deutschland, Ausgabe Süd, August 2000, S.23/25

3. Innovative Werkzeugsysteme zum Schleifen, Abrichten und Fräsen, Forum der Schneidwerkzeug- & Schleiftechnik 13. Jahrgang, Dezember 2000, S 4/14

4. Innovative Werkzeugsysteme zum Schleifen, Abrichten und Fräsen, Industrie Diamanten Rundschau 35 IDR (2001) 1, S.48/54

5. Innovative tool system for grinding, dressing and milling (T-Tool Profil and T-Tool), 16th International Conference on Production Research, ICPR-16, 29.07-03.08.2001, Praha, Czech Republic

6. An innovative system for grinding dressing and milling, Industrial Diamond Review, IDR 1, 2002, S. 37/40

7. T-Tool-Profil; Ein praktisches Einsatzbeispiel für die Innenrundbearbeitung, V. Seminar, Moderne Schleiftechnologie und Feinstbearbeitung“ Haus der Wirtschaft, Stuttgart, 13.04.2004

309

G76 Dry Grinding and Minimal Coolant Lubricant Contact Information: Professor Dr. Ing. Taghi Tawakoli Faculty of Mechanical Engineering University of Applied Science Furtwangen Jakob-Kienzle Str. 17 78054 VS-Schwenningen Germany Tel: +49-7720-307-4380 Fax: +49-7720-307-4208 Email: [email protected] Abstract: Dry Grinding and minimal coolant lubricant were studied under using of new tool concept of T-Tool and T-Tool Profile which showed the reduction of up to 90% the coolant needed for grinding process in comparison with conventional process. Also for dry grinding, a new tool with their subsidiary system are going to be developed as an accepted state proposal in Germany. Key Issues of the Work: • Development of new tools and systems to reduce the coolant lubricant • Development of new tools and systems for dry grinding Status: Not Completed Publications of this work: 1. T. Tawakoli: Minimalmengen-Kühlschmierung beim Schleifen, T-Tool Profil, Öl oder

Emulsion, IV. Seminar „Moderne Schleiftechnologie“ an der FH-Furtwangen, Neue Tonhalle Villingen, 25. April 2002

2. T. Tawakoli: Minimalmengen-Kühlschmierung beim Schleifen, Industrie Diamanten Rundschau 36 IDR (2002) 3, S.210/217

3. T. Tawakoli: Minimalmengen-Kühlschmierung beim Schleifen, T-Tool Profil, Horizonte 21 (2002), S. 38/44

4. T. Tawakoli: Minimum coolant lubrication in grinding, Industrial Diamond Review, IDR 1, 2003, S. 60/65

5. T. Tawakoli: Minimum lubrication and dry machining by grinding, T-Tool Profile, 17th International Conference on Production Research, (ICPR-17), Blacksburg, Virginia, USA, August 03-07, 2003

6. T. Tawakoli: Minimalmengen-Kühlschmierung beim Schleifen, T-Tool Profil, Tribologie und Schmiertechnik, 50. Jahrgang, 4/2003, S. 10/14

310

G77 High Speed High Efficiency Deep Grinding Contact Information: Professor Dr. Ing. Taghi Tawakoli Faculty of Mechanical Engineering University of Applied Science Furtwangen Jakob-Kienzle Str. 17 78054 VS-Schwenningen Germany Tel: +49-7720-307-4380 Fax: +49-7720-307-4208 Email: [email protected] Abstract: A lot of systematic researches showed the high capability of High Speed High Efficiency Deep Grinding specially in enormous increasing in material removal rate as well as proper workpiece surface quality (dimension, accuracy, roughness). It was found that using HEDG process, less tool wear, less heat generation on the workpiece surface and more compression residual stress with the same surface quality as creep feed grinding would be achieved. Key Issues of the Work: • New grinding process with very high material removal rate and more efficiency • Integrating high speed grinding with creep feed grinding Status: Completed 2001 Publications of this work: Most of the works regarding this theme were studied and published by Prof. Tawakoli before 2000. Here is just few papers.

1. T.Tawakoli: principal of chip formation by high speed cutting, university of central florida,

13.12.2000 2. T.Tawakoli: Theory of cutting process, high speed high efficiency deep grindng and new tool

systems, Fa. Norton, Wurcester, USA, 09.03.01 3. T.Tawakoli: Grundlagen des Zerspanungsvorgangs beim Hochgeschwindigkeit s-bzw.

Hochleistungsschleifen, Seminar Moderne Schleiftechnologie,14.05.1998, S 3-1

311

G78 Dressing of Vitrified CBN-Grinding Wheel Contact Information: Professor Dr. Ing. Taghi Tawakoli Faculty of Mechanical Engineering University of Applied Science Furtwangen Jakob-Kienzle Str. 17 78054 VS-Schwenningen Germany Tel: +49-7720-307-4380 Fax: +49-7720-307-4208 Email: [email protected] Abstract: Based on the systematic experiments using different types of dressing tools (Roll or Form dressing tool, Profile dressing tool, Crushing) and also by changing some of the dressing parameters (Velocity, Feed, Depth of cut), the optimum condition for dressing of defined vitrified CBN-Wheel were found. Also the affection of dressing parameters and dressing type on the topography of the grinded workpiece were studied. Key Issues of the Work: • Affection of dressing parameters on optimum condition of grinding (tool wear , grinding

force, workpiece surface topography and roughness) • Comparison between different type of dressing (Roll or Form dressing tool, Profile dressing

tool, Crushing) Status: not Completed Publications of this work: At the moment it is not permitted to publish any paper by our industrial partners, but they will be published soon.

312

G79 CNC-Contour-Grinding Contact Information: Dr. Volker Herold Friedrich-Schiller-University Jena Institute of Materials Science and Technology Loebdergraben 32 D – 07743 Jena Germany Email: [email protected]: http://www2.uni-jena.de/matwi/start.html.en Abstract: In CNC-Contour-Grinding form errors will occur mainly because of grinding forces /elastic deformations or because of the shape of the grinding wheel respectively grinding wheel wear. The aim of this project is to improve form errors by consideration of the shape of the grinding wheel or of the workpiece form of a previous grinding pass in the CNC program. The project relates to the grinding of various workpieces (mostly of ceramic materials), grinding of inner and outer surfaces, both grinding with straight wheels and cup wheels and both grinding with multiple passes and only one or two passes, but not deep grinding. Key Issues of the Work: • Contour grinding • Improvement of form errors Status: On-going Publications of this work: none

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GREECE

314

GR1 Development of Low Energy and Eco-efficient Grinding Technologies (ENGY) Contact Information: Professor George Chryssolouris Lab. For Manufacturing Systems & Automation (LMS) Dept. of Mechanical Engineering & Aeronautics University of Patras Patras, GR 26100 Greece Email: [email protected], [email protected] http: www.lms.mech.upatras.gr Abstract: The ENGY project is co-funded from the EC and the consortium is composed of 11 partners coordinated by DANOBAT. The overall scope of the project is the reduction of energy consumption and the development of eco-efficient grinding technologies. LMS role in this project is the theoretical investigation of both grinding and grind-hardening processes and the application of Life Cycle Assessment methodology on grinding machine tools and on grinding processes as to assess their environmental impact and identify potentials for improving their eco-efficiency. Key Issues of the Work: • Improve the eco-efficiency of the grinding machine tools and process itself • Theoretical simulation of grinding and grind-hardening processes Status: On-going Publications of this work: 1. Chryssolouris, G., Tsirbas, K., Zannis, S., 2001, An experimental investigation of grind-

hardening. Proceedings of the 34th CIRP International Seminar on Manufacturing Systems, pp. 121 – 123.

2. Chryssolouris, G., Tsirbas, K., Salonitis, K., 2005, An Analytical and Numerical Approach to Grind-Hardening, Accepted to be published in SME Journal of Manufacturing Processes.

315



GR2 Theoretical Modeling of Grind-Hardening Contact Information: Professor George Chryssolouris Lab. For Manufacturing Systems & Automation (LMS) Dept. of Mechanical Engineering & Aeronautics University of Patras Patras, GR 26100 Greece Email: [email protected], [email protected] http: www.lms.mech.upatras.gr Abstract: Grind-hardening process utilizes the heat generated during grinding for inducing heat treatment on workpiece surface. The process’ outcome depends on a number of factors such as the workpiece material, the grinding wheel composition, the presence of coolant fluid and of course the process parameters (workpiece/feed speed, grinding wheel speed and depth of cut). The effect of these factors on the process has been investigated theoretically and process simulation models have been derived for the simulation of the process. Key Issues of the Work: • Simulation of the grind-hardening process • Prediction of the hardness penetration depth and hardness profile Status: On-going Publications of this work: 1. Chryssolouris, G., Salonitis, K., 2004, Theoretical investigation of the Grinding Wheel Effect

on Grind-Hardening Process, Proceedings of the IFAC-MIM'04 Conference. 2. Chryssolouris, G., Tsirbas, K., Salonitis, K., 2005, An Analytical and Numerical Approach to

Grind-Hardening, Accepted to be published in SME Journal of Manufacturing Processes. 3. Salonitis, K., Tsoukantas, G., Stavropoulos, P., Stournaras, A., Chryssolouris, G., 2005, An

overview of grind-hardening modelling, will be presented in the PSDMH conference in March 2005.

4. Chryssolouris, G., Salonitis, K., Theoretical Investigation of the cooling application in grind-hardening operations, prepared to be submitted.

316



HOLLAND

317

H1 High Precision Machining of Small Bores Contact Information: Professor Bernhard Karpuschewski Department of Precision Machining and micro Assembly (PMA) Faculty of Mechanical engineering and marine technology Delft University of Technology Mekelweg 2 2628 CD Delft Holland Tel: +31 15 2783204 Fax: +31 15 2783910 Email: [email protected] http: www.wbmt.tudelft.nl/pto Abstract: The research focuses on the machining of small bores (2-6 mm diameter) in hardened steel. To achieve the desired quality a combined turning and grinding process on a single machine tool is proposed. The researcher is determining the influence of the length to diameter ratio of the bores. This will eventually give guidelines in what situations the combined process offers an advantage. Furthermore the influence of machining parameters on the achievable product quality and the cycle time will be studied. To enable this combined process a precision turning machine is equipped with a high speed grinding spindle. Key Issues of the Work: • Machining of small bores with a combined turning and grinding process Status: In progress Publications of this work: 1. B. Karpuschewski, A. M. Hoogstrate, V. Bana: High precision machining of small bores.

Annals of DAAAM & Proceedings of the 15th International DAAAM Symposium, 3-6th November 2004, Vienna, Austria, ISSN 1726 9679, ISBN 3 901509 42 9 pp. 201-202.

318

H2 Development of Flexible Equipment and Strategy for Profiling of Super-Abrasive Grinding Wheels Contact Information: Professor Bernhard Karpuschewski Department of Precision Machining and micro Assembly (PMA) Faculty of Mechanical engineering and marine technology Delft University of Technology Mekelweg 2 2628 CD Delft Holland Tel: +31 15 2783204 Fax: +31 15 2783910 Email: [email protected] http: www.wbmt.tudelft.nl/pto Abstract: For grinding with high accuracies and profiled wheels vitrified bonded grinding wheels are becoming more and more popular. The reason can be found in their potential to be profiled with high accuracies. To achieve highest accuracy, profiling and dressing should be done on the grinding machine, this removes errors associated with tool changes. Furthermore higher accuracies can be maintained as dressing can be done in shorter intervals. Because the tool does not have to be removed from the machine production times can be reduced. To achieve the above mentioned a profiling method based on the point-crushing process will be used. Point crushing exploits the brittleness of the binder material that holds the abrasive grains together. The profiling tool, a rotary disk, is synchronized with the grinding wheel in such a way that the relative speed in the contact point becomes zero. Because of this there will only be a normal force on the grinding wheel which will make the binder between the grains break and the grains drop out. The developed equipment will have significantly higher stiffness and damping than the present state-of-the-art, to reduce problems with vibrations. To create maximum profile flexibility the dresser will be equipped with an extra swiveling axes that will also facilitate reprofiling of the profiling tool on the machine. Key Issues of the Work: • Development of profiling equipment with speed synchronization and swiveling axes • Optimization of the dressing process Status: In progress Publications of this work: No publications yet

319

HONG KONG

320

HK1 Use of Fluid Beams to Establish a Clean Zone for In-Process Optical Measurement Contact: Yongsheng Gao Department of Mechanical Engineering Hong Kong University of Science and Technology Clear Water Bay, Kowloon, Hong Kong E-mail: [email protected] Abstract : An assisting fluid system is used to overcome the opaque barrier of coolant used in a precision machining process. In this new approach, a fluid beam is established through the use of an applicator to build a small zone that is optically clean, termed as transparent window, to enable the workpiece surface accessible to optical measurement systems. The advantages of the proposed method are that the wear problem of the contact methods and the inaccessibility problem of the non-contact methods are removed. This could permit the in-process optical measurement to reach a level of high precision, since the optical methods can be applied. Preliminary tests show that the proposed approach is feasible. Key Issues with the Work: • A very small clearance between the beam applicator and surface is required. • CFD was required to get the desired flow pattern Status: Completed Publications: 1. Gao, Y., Tse, S., and Lai, K., 2001, A Computational Investigation Of The Parameters To

Establish A Transparent Window For In-Process Optical Measurement, Proc. ISMQC2001 2. Gao, Y., and Tsa, Z., 2001, Test Of Flow Patterns Of Grinding Coolants Interfered Using An

Injection Of Stream, Proc. EUSPEN 2001, pp. 684-687.

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HK2 An Active Coolant Cooling System for Applications in Surface Grinding Contact: Yongsheng GAO Mechanical Engineering Department Hong Kong University of Science and Technology Clear Water Bay, Kowloon Hong Kong Fax: 852-2358-1543 E-mail: [email protected] Abstract: In many precision machining processes such as surface grinding, coolant is typically used to provide functions such as lubrication and cooling. In order to reduce surface grinding temperatures effectively, an active coolant cooling system is proposed. The system is based on the use of forced convection of the heat generated during the machining process. The coolant cooling system utilizes a commonly used air conditioner for ease of use and to reduce costs. In the proposed design, the evaporator of the heat pump is connected to the coolant tank of a surface grinding machine to reduce grinding temperatures for improved stability of accuracy and surface quality. This can be done without compromising production efficiency. System structure is explained and a coolant temperature model presented. Experimental testing on a prototype active cooling system is presented. The coolant temperature can be reduced to approximately -2 °C under no load condition, and to approximately 3 °C under loaded condition. The time constants of the cooling system were estimated. The results of the experimental tests demonstrated the effectiveness of the proposed system for applications in surface grinding for active coolant cooling in comparison with passive cooling. Key Issues with this Work: • To improve the energy efficiency, thermal insulation was provided for the heat exchanger. • For the proposed cooling system, a temperature model was established and a time constant

model developed. Status: Ongoing Publications: 1. Y. Gao, S. Tse, H. Mak, 2002, An Active Coolant Cooling System For Applications In

Surface Grinding, J. Applied Thermal Engineering 23 (2003) 523-537

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HK3 Composite Control for the Surface Grinding Process Contact: Yongsheng GAO Mechanical Engineering Department Hong Kong University of Science and Technology Clear Water Bay, Kowloon Hong Kong Fax: 852-2358-1543 E-mail: [email protected] Abstract: A novel scheme for composite grinding control which combines the advantages of both the wheel infeed system and a workpiece actuating table was developed. The PZT actuated table was designed to implement small but fast control actions and the wheel servo-motor infeed system designed to implement large but slow control actions. The dual control system allows the hardware costs to be reduced and dynamic capability of the grinding system to be enhanced. Control system models and control command generation have also been developed. Selective assignment of control tasks to different actuating units and experimental implementation were examined. In this scheme, the control commands of required motion will be decomposed and the two actuating units will work simultaneously but at different frequency ranges to generate a composite action. The control task distribution will be based on a selective assignment model. The resulting design can therefore reduce the hardware costs and permit faster active grinding control. Key Issues with this Work: • The position of the two actuating units and a composite control for the surface grinding

process has to be derived using complex algorithyms. • In the experiments for verification, a servo motor controlled wheel infeed system with a

linear encoder for position feedback and a workpiece actuating table using PZT with a built-in sensor for position feedback had to be designed and built.

Publications: 1. Gao, Y., and Jones, B., 1992, "A Discrete Control System Model for the Traverse Grinding

Process", Proc Institution Mechanical Engineers, Part I, J Systems and Control Engineering, Vol. 206, pp. 19-27.

2. Gao, Y., Tse, S., and Chui, K., 2003, A Displacement-Frequency Modulator based System for Composite Grinding Control, Proc. Advances inAbrasive Technology VI, ISAAT, pp.165-170, Bristol, UK

323


INDIA

324

IN1 Surface Integrity Studies on Grinding of SiC Contact Information: Dr.P.Venkateswara Rao Associate Professor Mechanical Engineering Department Indian Institute of Technology Delhi New Delhi – 110 016 INDIA E-mail: [email protected] Abstract:

This study indicates the influence of the grinding parameters on surface roughness and area of surface damage of SiC. A significant finding of this research is that the percentage area of surface damage decreases with an increase in feed rate and is not affected by the variation in grit density, within the domain of operating parameters. The empirical models, developed in this work, are used to ascertain optimal grinding conditions for maximization of material removal, using the surface roughness and percentage area of surface damage as constraints. The results show that the material removal and the cost of grinding are influenced by the surface roughness rather than the surface damage. The GA approach adopted is ideally suitable for planning processes in a computerized environment such as the Computer aided process planning (CAPP) systems that are now being commonly practiced. An attempt has been made to assist the manufacturers to select process parameters depending on the functional requirement of the product.

In order to look into the aspects of obtaining better surface quality, investigations were carried out to introduce graphite as a solid lubricant. A new cost effective experimental set-up was developed. An improvement in surface finish was obtained under graphite assisted grinding. It was observed that there was a considerable reduction of tangential force, thereby reducing the specific grinding energy needed and consequently reducing the damage introduced by the grinding process.

Another area of focus of this study was the development of a modified chip thickness model to give more insight into the grinding process. The modification includes the incorporation of the elastic properties of the wheel and the workpiece by introducing an exponent ‘n’. The methodology required for evaluating exponent ‘n’ for a given set of wheel and workpiece material has been established. The new model yields results that agree reasonably well with the experimental results. Hence the new model can now be used to make better predictions for grinding of SiC. Key issues: • Optimization of grinding of SiC • Performance improvement of grinding of SiC using Graphite lubrication

325


• Development of modified Chip thickness model Status: On-going Publications of this work: 1. Venugopal, A. and Venkateswara Rao, P., “Optimization of Grinding of Silicon Carbide with Diamond Wheels Using Genetic Algorithms ”, The International Journal of Advanced Manufacturing Technology, Vol.22, No.7-8, 2003, pp.475- 480. 2. Venugopal, A. and Venkateswara Rao, P., “Selection of Optimum Conditions for Maximum Material Removal Rate with Surface Finish and Damage as Constraints in SiC Grinding”, International Journal of Machine Tools and Manufacture, Vol.43, No.13, 2003, pp.1327-1336. 3. Venugopal, A. and Venkateswara Rao, P., “Performance Improvement of Grinding of

Sic Using Graphite As a Solid Lubricant”, Journal of Materials & Manufacturing Processes, Vol.19, No.2, 2004, pp.177-186.

4. Venugopal, A. and Venkateswara Rao, P., “A New Chip Thickness Model for Performance Assessment of Silicon Carbide Grinding”, International Journal of Advanced Manufacturing Technology, Vol.24, No.11-12, 2004, pp.816-820.

326

IN2 Parametric Study Of Temperature Distribution In Electro-Discharge Diamond Grinding

Contact Information Prof. V. K. Jain Department of Mechanical Engineering Indian Institute of Technology Kanpur (INDIA)-208 016 e-mail : [email protected]: http://home.iitk.ac.in/~vkjain/ Abstract The Electro-discharge diamond grinding (EDDG) has been proved as a potential process for machining of components made of advanced engineering materials but it seem to be rather lacking in theoretical treatment of the EDDG process. This paper reports on determination of temperature distribution in the workpiece due to EDDG using finite element method (FEM). The temperature distribution in whole workpiece domain due to EDDG is obtained by superposition of the two temperature distributions in grinding and in EDM i.e. 2-D for grinding and axi-symmetric for EDM. The effects of duty cycle, on-time, current, energy partition, time of machining, and feed velocity are computationally investigated. Key issues of the work : • Temperature distribution on the workpiece surface during electric discharge diamond

grinding. • Comparison with the measured temperature / reported temperature by other researchers in the

literature. Status : Completed

Publication of this work : 1. Yadav, Vinod, Jain V.K., Dixit, Parametric Study Of Temperature Distribution In Electro-

Discharge Diamond Grinding, P. M., 2004,

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IN3 Temperature Distribution in the Workpiece During Diamond Surface Grinding using FEM

Contact Information Prof. V. K. Jain Department of Mechanical Engineering Indian Institute of Technology Kanpur (INDIA)-208 016 e-mail : [email protected]: http://home.iitk.ac.in/~vkjain/ Abstract

The study of temperature distribution on the workpiece surface during grinding is important from the quality of product point of view. High temperature during grinding leads to the surface characteristics like burn marks, micro-cracks, and thermal residual stresses, which are detrimental to the products. Applications of the diamond grinding are becoming more popular despite of its high cost requirements. Keeping this in view, a numerical thermal model has been developed for the analysis of pendulum and creep feed grinding. This paper predominantly deals with the effects of heat flux magnitude, and its distribution (or type), table speed, and depth of cut on the critical top surface temperature distribution of the workpiece during diamond surface grinding of HSS workpiece.

Key issues of the work : Status : Completed

Publication of this work: 1. Vinod Yadava, V.K.Jain, and P.M. Dixit, 2003,: " Temperature Distribution In The Workpiece

During Diamond Surface Grinding Using FEM" Proceedings of 20th AIMTDR conference held at Birla Institute of Technology, Mersa Ranchi, pp 187-194

328



IN4 Theoretical Analysis Of Thermal Residual Stresses In Electro-Discharge Diamond Grinding

Contact Information Prof. V. K. Jain Department of Mechanical Engineering Indian Institute of Technology Kanpur (INDIA)-208 016 e-mail : [email protected]: http://home.iitk.ac.in/~vkjain/ Abstract Excessive heat generated at the machining zone, during electro-discharge diamond grinding (EDDG), is the major cause of thermal stresses, untempered martensite, over tempered martensite, and cracks. Therefore, the key to achieve good surface integrity in a machined part is to prevent excessive temperature and thermal stresses generated during machining process. A finite element model has been developed to estimate thermal stresses during EDDG when the current is switched off. First, the developed code calculates the temperature in the workpiece and then the thermal stress field is estimated using this temperature field. Computations were carried out in a plane strain condition for different ground fields of the grinding wheel. The effects of time of grinding and feed, on thermal stress distribution have been reported. The thermal stresses are found to be higher near top surface at initial time of grinding but shifted away towards bottom after some grinding time. Key issues of the work : • Analysis of thermal residual stresses during electric discharge diamond grinding. • Evaluation of thermal residual stresses and parametric analysis of the process with

reference to thermal residual stresses. Status : Completed

Publication of this work: 1.

2.

Vinod Yadava, V.K.Jain, and Prakash M. Dixit, 2004,: "Theoretically Analysis Of Thermal Stresses In Electro-Discharge Diamond Grinding", Machining Science and Technology Vol. 8, No. 1, pp.119-140. Vinod Yadava, V.K.Jain, and Prakash M. Dixit, 2002,: "Thermal Stresses Due To Electrical Discharge Machining", Int. J. of Mach. Tools % Manu., Vol. 42, pp. 877-888

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IRELAND

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IR1 Modeling and Simulation of the Rotational Grinding Process Contact Information: Eamonn Ahearne Department of Mechanical Engineering University College Dublin, Belfield, Dublin 4 Ireland Tel: +353 (0)1 7161996 Fax: +353 (0)1 2696035 Email: [email protected] http: www.ucd.ie/mecheng/ams Abstract: Precision grinding is an enabling technology for the production of silicon and other semiconductor substrates for integrated circuits and MEMS (micro-electromechanical systems) devices. More specifically, rotational grinding is the “state of art” configuration proposed for generating surfaces of extreme form and finish by ductile mode grinding. An adaptive stochastic algorithm that simulates the locally varying microgrinding mechanics is described. The core concept of the algorithm enables the development of a modular software structure so that modules can be added or removed to simulate more complex or simpler models. The results of the simulation can be potentially related to locally varying normal and inplane forces in rotational grinding, as well as surface finish. The simulation-software may be used for machine and tool design, and overall process optimisation. A set-up for testing and validating the model has been proposed and scheduled for 2005.

Key Issues of the Work: • Relating the stochastic model outputs to forces (theoretically and empirically); developing a

measurement system for locally varying forces Status: Commenced 2004 Publications of this work:

Publication Pending for 8th CIRP International Workshop on Modeling of Machining Operations, Chemnitz, Germany May10-11, 2005: Ahearne, E. and Byrne, G. “Modeling and Simulation of the Rotational Grinding Process”.

1.

331

IR2 Mist Jet Cooling of Grinding Processes Contact Information: Prof. Andrew Torrance, Head of Dept. Dept. of Mechanical and Manufacturing Eng. Trinity College University of Dublin Dublin 2 Ireland Tel: 1 608 1729 Fax: 1 679 5554 Email: [email protected] www.mecheng.tcd.ie/~torrance Abstract: One of the problems in modern grinding processes is the use and disposal of coolants, which are expensive and which can lead to ecological problems. This paper describes some experiments with a novel method of cooling the grinding process which relies on nothing but air and water for its effect, thus removing ecological hazards in a most economical way. By injecting a small amount of water into air jets which strike the grinding wheel at speeds near mach 1, it is possible to maintain a sharper wheel and better cooling than with conventional coolants and delivery systems. It is relatively simple and cheap to set up the delivery system proposed, provided the correct nozzle designs are used. The following conclusions came out of the study:

1. High speed water mist jets seem to be a cheap and effective way of cleaning the wheel and reducing specific energies for grinding structural steel, even at low downfeeds.

2. The best effects are achieved with two mist jets, one at the front and one at the back of the arc of cut.

3. Mist jets also provide significant convective cooling of the arc of cut, which increases with water flow rate, but the mechanism cannot be determined from these results.

4. Addition of soap to the mist reduces specific energies and temperatures further. Key Issues of the Work: Demonstrates grinding performance equal to or better than performance with conventional fluids with small flows of ecologically friendly fluids. The main issues are now how best to apply these findings in an industrial setting, and how to optimize the technique for different processes. Status: The process is demonstrated as effective, but has not yet been applied industrially. Publications of this work: 1. D. Babic, D.B.Murray and A.A.Torrance, Mist jet cooling of grinding processes. Int. J. of

Machine Tool Design and Research to be published 2005. 2. D.M. Babic, A.A.Torrance and D.B.Murray, Soap Mist jet cooling of grinding processes.

Submitted to ISAAT 2005 St. Petersburg, Russia.

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ITALY

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IT1 Grinding of Metal Matrix Composites (MMCs) Contact Information: Professor Antoniomaria Di Ilio Faculty of Engineering Department of Mechanical Engineering University of L'Aquila 67040 Roio Poggio - L'Aquila Italy Tel: +39 0862 434318 Fax: +39 0862 434303 Email: [email protected] http:www.ing.univaq.it Abstract: The research aims to establish the best grinding parameters in order to achieve good surface quality and low tool wear in the grinding of Aluminium-SiC metal matrix composite. An experimental equipment has been set-up on a horizontal grinding machine that allows the monitoring of forces, temperature and active surface images of the grinding wheel, which are related to off-line measurement results on the machined parts such as roughness and optical and SEM analisys. The influence of the grinding parameters on the surface quality and tool wear have been obtained. Key Issues of the Work: • Improving knowledge on the grinding mechanisms of MMCs • Multi-sensor monitoring of the grinding process. Status: Completed 2003 Publications of this work: 1. Di Ilio, A. Paoletti, V. Tagliaferri, F. Veniali : "An Experimental Study on Grinding of

Silicon Carbide Reinforced Aluminium Alloys", International Journal of Machine Tools & Manufacture, Vol. 36, No. 6, pp. 673-685, June, 1996.

2. Di Ilio, A. Paoletti : “A Comparison Between Conventional Abrasives and Superabrasives in Grinding of SiC-Aluminium Composites”, International Journal of Machine Tools & Manufacture, Vol. 40, No. 2, pp. 173-184, January, 2000.

3. Di Ilio, A. Paoletti : "Wheel Topography Evaluation During the Grinding of SiC Reinforced Aluminium Alloy", Proceedings of the First World Conference on Integrated Design & Process Technology, Austin, Texas, pp. 70-76, 6-9 December, 1995.

4. Di Ilio, A. Paoletti, V. Tagliaferri : "Modelling of the Grinding Process of SiC-Aluminium Composites”, Proceedings of the Second World Conference on Integrated Design & Process Technology, pp. 267-273, Austin, Texas, 1-4 December, 1996.

5. Di Ilio, A. Paoletti : "Influence of Tool Geometry and Cutting Parameters on the Machinability of SiC-Aluminium Composites", Proceedings of Advancing with Composites 2000, pp. 185-192, Milan, 9-11 May, 2000.

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6. Di Ilio, A. Paoletti: “Monitoring Techniques for Evaluation of Grinding Wheel Cutting Ability in Machining of Metal Matrix Composites”, Proceedings of 1st International Seminar on Progress in Innovative Manufacturing Engineering, pp. 167-172, Sestri Levante (Genoa), 20-22 June, 2001.

7. Di Ilio, A. Paoletti: "Technological Models Based on Grinding Wheel and Workpiece Characteristics in the Grinding Process of MMCs”, Proceedings Sixth Conference on Advanced Manufacturing Systems and Technology ’02, pp. 193-202, Udine, 20-21 June, 2002.

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IT2 Residual Stresses in Grinding Contact Information: Professor Antoniomaria Di Ilio Faculty of Engineering Department of Mechanical Engineering University of L'Aquila 67040 Roio Poggio - L'Aquila Italy Tel: +39 0862 434318 Fax: +39 0862 434303 Email: [email protected] http:www.ing.univaq.it Abstract: This research aims to study the residual stresses on grounded parts made of steel or magnetic materials. Analytical and numerical models for temperature and stresses have been developed and the results have been related to the experimental measurements of residual stresses obtained on grounded workpieces by-means of x-ray diffraction method. Further improvement is currently done on the monitoring equipment of the grinding process. Key Issues of the Work: • Improving the surface integrity of grounded workpieces Status: On-going. Publications of this work: A thesis has been concluded and a scientific paper is in progress.

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IT3 Wear Models for Diamond Tools on Stone Contact Information: Professor Antoniomaria Di Ilio Faculty of Engineering Department of Mechanical Engineering University of L'Aquila 67040 Roio Poggio - L'Aquila Italy Tel: +39 0862 434318 Fax: +39 0862 434303 Email: [email protected] http:www.ing.univaq.it Abstract: The aim of the research is to study the wear mechinsms of diamond abrasive sawblades and mills when machining natural stones, in order to find the optimum set of parameters. An analytical model has been developed and validated by means of experimental results obtained in cutting and milling of different marbles and granites. At the moment the research is addressed to the finishing processes of marbles and granites in order to improve the surface quality and to make the use of diamond tools more economical. Key Issues of the Work: • Developing tool life models in the cutting of natural stone. • Improving surface quality and tool life in polishing natural stones. Status: Cutting: completed 2003, polishing: On-going. Publications of this work: 1. Di Ilio, A. Paoletti, A. Togna: “Tool Wear in Stone Cutting: Theoretical Model and

Experimental Validation ”, Atti del &° Convegno A.I.TE.M, Cassino, 8-10 September, 2003. 2. Di Ilio, A. Togna, A., "A Theoretical Wear Model for Diamond Tools in Stone Cutting", Int.

J. Machine Tools & Manufacture, vol. 43, pp. 1171-1177, 2003. 3. Di Ilio, A., Paoletti A. Togna, A., Turchetta, S. "Tool Wear in Stone Cutting: Theoretical

Model and Experimental Validation", Roc Maquina - Dimension Stone Industry, n. 3, March, pp. 22-27, 2004.

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JAPAN

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J1 Internal Machining of Small Hole by Ultrasonically Assisted Grinding (UAG) Contact Information: A/Prof. Dr. Yongbo Wu Depat. Of Machine Intelligence and Systems Engineering Akita Prefectural University 84-4 Tsuchiya-Ebinokuchi, Honjo Akita 015-0055, Japan Email: [email protected] http:www.akita-pu.ac.jp Abstract: In order to develop an alternative novel method for the internal precision machining of small holes measuring several millimeters in diameter, a constant depth-of-cut UAG technique has been proposed. An experimental apparatus composed mainly of an ultrasonic vibration spindle was designed and constructed. Fundamental grinding experiments have been carried out in order to investigate the effects of the ultrasonic vibration on grinding force and surface roughness. The obtained results showed that applying ultrasonic vibration to the grinding wheel decreases the normal and tangential grinding forces by more than 65% and 70%, respective, and the surface roughness by as much as 29%. Further experimental and theoretical investigations indicated that the decrease in grinding force is due to the grinding chips becoming smaller and fracturing more easily under ultrasonication. Key Issues of the Work: • Proposing a UAG (Ultrasonically Assisted Grinding) method for the internal precision

machining of small holes. • Developing a internal UAG equipment mainly composed of a ultrasonic vibration spindle. • Clarifying the fundamental characteristics of UAG such as the effects of ultrasonication on

the grinding force and surface roughness. Status: On-going Publications of this work: 1. Yongbo Wu, Mitsuyoshi Nomura, Zhijing Feng and Masana Kato, Modeling of Grinding

Force in Constant-Depth-of-Cut Ultrasonically Assisted Grinding, Materials Science Forum, Vols. 471-472, 2004, pp.101-106.

2. Yongbo Wu, Mitsuyoshi Nomura, Masana Kato and Toru Tachibana, Fundamental Investigation of Internal Ultrasonic Vibration Assisted Grinding of Small Holes, Proceedings of International Conference on Leading Edge Manufacturing in 21th Century (LEM21), Nov. 2003, pp.145-150.

3. Yongbo Wu, Mitsuyoshi Nomura, Masana Kato and Toru Tachibana, Studies on Precision Internal Grinding of Small Holes with Ultrasonically Vibrated Grinding Wheel (Development of an Ultrasonic vibration Spindle and its Basic Performance in Grinding Operations), Journal of the Japan Society for Abrasive Technology (JSAT), Vol.47, No.10, 2003, pp.550-555.

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J2 Studies on Centerless Grinding Contact Information: A/Prof. Dr. Yongbo Wu Depat. Of Machine Intelligence and Systems Engineering Akita Prefectural University 84-4 Tsuchiya-Ebinokuchi, Honjo, Akita 015-0055, Japan Email: [email protected] http:www.akita-pu.ac.jp Abstract: Experimental and Theoretical studies of centerless grinding have been conducted in respect of the workpiece rounding mechanism, the simulation investigation of workpiece rounding process, the determination of optimum grinding conditions, the real time monitoring of grinding process, the influence of grinding wheel irregularity on workpiece roundness, the evaluation of grinding conditions using dynamic components of grinding force, and the wear deviation of regulating wheel and its influence on grinding accuracy. Through a series of investigations, (1) the workpiece rounding process has been clarified; (2) a technique for monitoring the grinding process in real time has established to realize a stable grinding operation; (3) the influences of the grinding wheel irregularity and the wear deviation of regulating wheel on the grinding accuracy have been discussed in details and thus the guide line for truing both the wheels was provided; (4) an unique technique using grinding force dynamic components was proposed to evaluate the grinding conditions for optimizing the grinding conditions. Key Issues of the Work: • Developing the grinding force measurement method and its apparatus in centerless grinding • Clarifying the workpiece rounding mechanism • Monitoring and computer simulating the workpiece rounding process • Determining the optimum grinding conditions • Developing the evaluation method for grinding conditions • Investigating the influence of disturbance such as the irregularity of grinding wheel and the

wear deviation of regulating wheel on the grinding accuracy Status: On-going Publications of this work: 1. Yongbo Wu and Masana Kato, Geometrical Arrangement of ID Grinding Wheel in

Simultaneous-ID/OD Combination Centerless Grinding, Proceedings of 7th International Symposium on Advances in Abrasive Technology, June, 2004, pp.301-305.

2. Yongbo Wu, Masana Kato, Katsuo Syoji, Tsunemoto Kuriyagawa and Toru Tachibana, Wear Deviation of Regulating Wheel and its Influence on Workpiece Accuracy in Centerless Infeed Grinding, Transactions of the Japan Society of Mechanical Engineers (JSME), Series C, Vol.68, No.671, 2002, pp.2145-2150.

3. Yongbo Wu, Katsuo Syoji, Tsunemoto Kuriyagawa, Toru Tachibana and Masana Kato. Evaluation of Grinding Conditions by Detecting the Dynamic Components of Grinding Force in Centerless Grinding. Journal of the Japan Society for Precision Engineering (JSPE),

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Vol.67, No.9, 2001, pp.1443-1447. 4. Yongbo Wu, Katsuo Syoji, Tsunemoto Kuriyagawa and Toru Tachibana. Studies on

Centerless Grinding (Influence of Grinding Wheel Irregularity on Workpiece Roundness). Transaction of the Japan Society of Mechanical Engineering (JSME), Series C, Vol.66, No.649, 2000, pp.3162-3167.

5. Yongbo Wu, Masana Kato, Katsuo Syoji and Tsunemoto Kuriyagawa, Design of Grinding Cycle in Centerless Infeed Grinding, in: Advances in Abrasive Technology, edited by N. Yasunaga, J. Tamaki, K. Suzuki and T. Uematsu, Journal of the Japan Society for Abrasive Technology (JSAT), 2000, pp. 268-273.

6. Yongbo Wu, Masana Kato, Katsuo Syoji and Tsunemoto Kuriyagawa, Investigation of Workpiece Rounding Process and Optimum Grinding conditions in Centerless Grinding, Proceedings of 2000 International Conference on Advanced Manufacturing Systems and Manufacturing Automation, June 2000, pp. 1026-1029.

7. Yongbo Wu, Katsuo Syoji and Tsunemoto Kuriyagawa. Investigation of Centerless Grinding (1st Report). International Journal of the Japan Society for Precision Engineering (JSPE), Vol.33, No.3, 1999, pp.185-190.

8. Yongbo Wu, Tsunemoto Kuriyagawa and Katsuo Syoji: Real Time Monitoring of Centerless Grinding Process Using Wavelet Transform, in: Abrasive Technology, edited by J. Wang, W. Scott and L. Zhang, World Scientific, 1999, pp.25-30.

9. Yongbo Wu, Katsuo Syoji, Tsunemoto Kuriyagawa and Toru Tachibana. Studies on Centerless Grinding (3nd Report)-Evaluation Function of Grinding Conditions. Journal of the Japan Society for Precision Engineering (JSPE), Vol.65, No.6, 1999, pp.862-863.

10. Yongbo Wu, Katsuo Syoji, Tsunemoto Kuriyagawa and Toru Tachibana. Studies on Centerless Grinding (2nd Report)-Optimum Grinding Conditions-. Journal of the Japan Society for Precision Engineering (JSPE), Vol.62, No.3, 1996, pp.433-437.

11. Yongbo Wu, Katsuo Syoji and Tsunemoto Kuriyagawa. Studies on Centerless Grinding (1st Report, Grinding Force Measurement). Journal of the Japan Society for Precision Engineering (JSPE), Vol.61, No.3, 1995, pp.411-414.

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J3 Combined Micro Fabrication System using Both Laser and Microgrinding Contact Information: Professor Takuya Senba Fukuoka Institute of Technology Japan Email: [email protected] http:www.fit.ac.jp/～senba/ Abstract: Experimental research to fabricate electroformed diamond tool with superior bending strength has been made to fabricate microstructures in high-speed. It was verified through grinding tests that rough micro machining system should be developed to increase the efficiency of microgrinding. Hence, the attempt to make combined micro fabrication system using both laser and microgrinding has been carrying out. Key Issues of the Work: • Electroformed diamond tool • Combined micro fabrication system using both laser and microgrinding Status: On-going Publications of this work: 1. T.Senba, N.Tomita, S.Fujii, 2004, Development of High-Speed Electroforming Technique,

Transaction of the JSME, Vol.69, No.679, pp.217-223.

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J4 Fabrication Of Metal-Bonded Grinding/Polishing Tools By The Greentape Laser Sintering Method

Contact Information: K. Maekawa Department of Mechanical Engineering Res. Center of Superplasticity Ibaraki University 4-12-1 Nakanarusawa Hitachi 316-8511 Japan Fax: +81 294 38 5047 Email: [email protected] Abstract : The researcher has developed a new methodology of fabricating metal-bonded grinding/ polishing tools by the greentape laser sintering method. The porosity of copper sintered parts is utilizd for manufacturing grinding/polishing tools containing cubic boron nitride (CBN) or alumina abrasives. The novelty of the GTLS method lies in the use of a thin tape consisting of micro powder and organic binder. The slurry, mixed with powder, organic binder and solvents, is poured on to a plastic carrier sheet, then leveled to a specific thickness by rollers, then dried; finally tape and sheet are wound into a roll. The name "greentape" comes from the state of the objects before sintering. The greentape laser sintering (GTLS) method can be regarded as particle assembly based on rapid prototyping technology, and has been developed further in the present study. Copper-bonded CBN and aluminium oxide tools have been manufactured by the GTLS method and used to polish an austenitic stainless steel to a mirror surface. The GTLS method has the advantages of a short fabrication time and a large choice of materials and tool shapes, in addition to the presence of pores. Further investigation of the practical application of GTLS tools will be done. Publications of this Work: 1. Maekawa, K., Yokoyama, Y., and Ohshima, I., 1999, Fabrication of Metal-Bonded

Grinding/Polishing Tools by the Greentape Laser Sintering Method, 3rd Int. Conf. On Abrasive Technology, Brisbane, Australia.

2. Maekawa, K., Kokura, S., Ohshima, I. and Yokoyama, Y, Laser Micro Fabrication Using Thin Powder Tapes- Process Architecture And Feasibility Investigation, Proc. 31st CIRP Int. Seminar on Manufacturing Systems, Berkeley, California, USA, May 26-28, 1998:146-151.

3. K. Maekawa, S. Kokura, I. Ohshima and Y Yokoyama, Laser Micro Fabrication Using Thin Powder Tapes - Process Architecture And Feasibility Investigation, J. Manufacturing Systems, CIRP, 1999, 29(2):131-135.

4. K. Maekawa, Y. Yokoyama and I. Ohshima, Fabrication Of Metal-Bonded Grinding/ Polishing Tools By The Greentape Laser Sintering Method. Abrasive Technology, Current Development and Applications I, J. Wang et al. (eds). World Scientific, 1999:65-72.

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J5 Adaptive Robotic System for 3D Profile Grinding and Polishing Contact Information: Professor Zhou Libo System Engineering Departmentt. Ibaraki University Nakanarusawa 4-12-1, Hitachi Japan 316-8511 TEL/FAX (+81)-294-38-5217 http://pel.dse.ibaraki.ac.jp/ Abstract: Turbine vanes in an old jet engine can be severely worn and distorted, and cracks are often formed on their airfoils after service in high-temperature and high-pressure environments for long periods. The vanes need to be repaired, as replacement is far more expensive. In an overhaul process, defective areas on the vane airfoil are covered with a layer of braze material. Skilled workers then have to remove the excessive braze material using abrasive belt grinding and polishing to restore the original profile of the airfoil. The process is labor intensive, time consuming and quality inconsistent and has health concerns. Automation of such a process can lead to significant cost reduction and improved quality. Applications of CNC machining center or robotic machining system could be natural selection for automating the process. In recent years, robotic machining has attracted much attention in manufacturing industries. It has advantages compared with CNC machining, such as higher flexibility, greater capability of integration with sensors and actuators and lower cost. Industrial robots were proven to be an economic solution for automation of those operations under well defined conditions such as deburring, chamfering, finishing and even chiseling. However, for 3 dimensional profile vane repair, practical applications of robotic machining is still at the infant stage due to the severely distorted geometry condition. So far, an automated system for the grinding and polishing of turbine vanes has yet to be applied in the overhaul industry. The study reports the successful development of an automated robotic machining system for turbine vane overhaul. The perspectives and approaches of the 3D profile grinding and polishing system can be described. Key Issues of the Work: Status: Completed Publications of this Work: 1. Chen X.Q, Gong Z, Huang H, Ge S. and Zhou L. (Chapter 2: Process Development and

Approach for 3D Profile Grinding/Polishing, Chapter 3: Adaptive Robotic System for 3D Profile Grinding/ Polishing), "Advanced Automation Techniques in Adaptive Material Processing", World Scientific Publishing Co. 2002, pp. l9-90. [Book]

2. H. Huang, Z.M. Gong, X.Q. Chen and L. Zhou, Smart Robotic System for 3D Profile Turbine Vane Airfoil Repair. Int'l Journal of Advanced Manufacturing Technology, Vol.21, 4(2003), pp. 275-283.

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3. H. Huang, Z.M. Gong, X.Q. Chen, L. Zhou: Robotic grinding and polishing for turbine-vane overhaul. Journal' of Material Processing Technology, Vol. 124, Issue 2(2002), pp.140-145.

4. Libo Zhou and Han Huang: Automated Robotic System for Jet Engine Overhaul, - System Design and Development for Honeycomb Repair -, Int'l Journal of Advanced Manufacturing Technology, Vol.19, 5 (2002), pp. 370-376.

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J6 Asymmetric Aspherical Form Generation for Large Optical Components by Grinding Contact Information: Professor Zhou Libo System Engineering Departmentt. Ibaraki University Nakanarusawa 4-12-1, Hitachi Japan 316-8511 TEL/FAX (+81)-294-38-5217 http://pel.dse.ibaraki.ac.jp/ Abstract: Proposed in this study is a new method for axisymmetric form generation. The equipments required is a face grinding machine with two spindles configured as one (grinding wheel) to face another (for workpiece). The infeed grinding is applied at the position of the wheel half overlapped against the workpiece. When the axes of two spindles are set to be parallel, the interference between the wheel and workpiece are made in a plan perpendicular to the axes so that the profile formed is flat. Other than the above condition, the forms are in axisymmetric three-dimension. By taking account of the extra effects of cutting path density, it is further able to give a variation in concave or convex profiles of corn, spherical or ellipse shapes. This new method receives no effect of tool wear, therefore, is effective in form generation for large diameter optical components. The newly proposed method has been applied to �200mm optical glass in this research to produce a flat-convex lens Key Issues of the Work: Status: Ongoing Publications of this Work: 1. L. Zhou. J. Shimizu and H. Eda, Axisymmetric Aspherical Form Generation for Large

Diamond Optical Components, Key Engineering Materials, Vol. 257-258(2004), pp.101-106.

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J7 One-Stop Grinding Machine and Process for 300mm Diameter Wafers Contact Information: Professor Zhou Libo System Engineering Departmentt. Ibaraki University Nakanarusawa 4-12-1, Hitachi Japan 316-8511 TEL/FAX (+81)-294-38-5217 http://pel.dse.ibaraki.ac.jp/ Abstract: Material removal takes place at three different modes; elastic mode, plastic/ductile mode and brittle mode, which are respectively correspondent to elastic deformation, plastic flow and fracture initiation. The silicon is subject to plastic flow when the strain is restrained within 0.02% ~ 0.03%. At the range of corresponding depth of cut, the material is removed at ductile mode so that no crack remains after machining. But still, there is plastic strain developed. In order to further reduce plastic flow, a smaller removal rate is preferable. Polishing is a process possible to produce a surface almost free of plastic strain, but at an extremely low removal rate. As it is established on pressure controlled infeed mechanism, polishing is unable to meet the requirement of flatness as the wafer size increases. The objective of the research is to develop a machining system by use of a single grinding wheel (fixed abrasive process) to directly finish a sliced wafer up to the quality equivalent to or better than that achievable by polishing. In this research, a hybrid of position and pressure controlled infeed mechanism has been developed to realize both ductile mode grinding and polishing-like finishing at a single set-up. Ductile mode grinding is first executed to remove any possible defect layer generated at the preceding process, and then followed by a polishing-like finishing to produce a defect-free surface. Key Issues of the Work: Status: Ongoing Publications of this Work: 1. Libo ZHOU. Hiroshi EDA, Jun SHIMIZU, State-of-the-art Technologies and Kinematical

Analysis for One-Stop Finishing of 300mm Si Wafer, Journal of Material Processing Technology, Vol.129, Issues 1-3(2002), pp.34-40.

2. H. Eda, L. Zhou. H. Nakano, R. Kondo, J. Shimizu, Development of Single Step Grinding System for Large Scale 300mm Si Wafer - A Total Integrated Fixed-Abrasive Solution, CIRP Annals, Vol.50, 1(2001). pp.225-228

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J8 Chemo-Mechanical Grinding Technology Contact Information: Professor Zhou Libo System Engineering Department. Ibaraki University Nakanarusawa 4-12-1, Hitachi Japan 316-8511 TEL/FAX (+81)-294-38-5217 http://pel.dse.ibaraki.ac.jp/ Abstract: As finishing techniques for Si wafers, the free abrasive processes like lapping and polishing are able to offer a better surface roughness when finer abrasives are applied, but fall short of maintaining profile accuracy when the wafer size increases. On the other hand, the fixed abrasive process or grinding is known as a promising solution to improve accuracy of profile geometry, but always has subsurface damages remaining after machining. In order to simultaneously achieve both surface quality and geometry accuracy, this research has proposed a new chemo-mechanical-grinding (CMG) process by effective use of chemical reaction in the grinding process. CMG wheels which contain chemically active abrasives and additives have been developed, characterized and applied into grinding of 300mm diameter bare Si wafers. The ground wafers are examined on both surface and subsurface. The results show no subsurface damage produced due to machining. A defect-free surface so far only achievable by polishing has been realized by the fixed abrasive process. A discussion is also made to understand the mechanism and chemical reaction involved in the process. Key Issues of the Work: Status: Ongoing Publications of this Work: 1. Libo Zhou. Jun Shimizu and Hiroshi Eda, A Novel Fixed Abrasive Process: Chemo-

Mechanical Grinding, Technology, International Journal of Manufacturing Technology and Management, (submitted 2004)

2. L. Zhou. S. Kawaii, S. Kimura, J. Shimizu, and H. EDA, Development of Chemo-Mechanical Grinding (CMG) Process, Proc. of International Conference on LEM21 (Leading Edge Manufacturing in 21st Century), Niigata, pp.315-320, 2003.

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J9 Molecular Dynamics Simulation, and Experimental Analysis, of Super High-Speed Grinding of Ductile Materials

Contact Information: Professor Zhou Libo System Engineering Departmentt. Ibaraki University Nakanarusawa 4-12-1, Hitachi Japan 316-8511 TEL/FAX (+81)-294-38-5217 http://pel.dse.ibaraki.ac.jp/ Abstract: This study aims to reduce the work-affected layer of the machined surface by carrying out the grinding at the speed over static propagation speed of plastic wave of ductile materials and also aims to clarify the machining mechanism at such super high-speed. This study reports on the result obtained through the molecular dynamics simulations and experiments on the super-speed grinding below and beyond static propagation speed of aluminum. From the simulation results, it is verified that the plastic deformation is reduced when the machining speed exceeds the material static propagation speed of plastic wave and its mechanism is completely different from that of the ordinary grinding process. Experimental results also show the improvement of the surface integrity when the machining speed exceeds the material static propagation speed of plastic wave. Key Issues of the Work: Status: Completed Publications of this Work: 1. J. Shimizu, L. ZHOU and H. EDA: Molecular Dynamics Simulation of Contact Process in

AFM Surface Observation, Tribotest Journal, Vol.9, 2(2002), pp.101-115. 2. Jun Shimizu, Libo Zhou and Hiroshi Eda, Molecular Dynamics Simulation of Contact

Process in AFM/FFM Surface Observation, - Influence of cantilever stiffness on atomic force images, Tribology International, (submitted)

3. K. Ramesh, S. H. Yao, S. Gowri and L. Zhou, Experimental Evaluation of Super High-Speed Grinding of Advanced Ceramics, Int'l Journal of Advanced Manufacturing Technology, Vol. 17(2001), pp.87-92

4. J. Shimizu, L. Zhou and H. Eda, Molecular Dynamics Simulation of Material Removal Mechanism beyond Propagation Speed of Plastic Wave, Proc. of International Conference on LEM21 (Leading Edge Manufacturing in 21st Century), Niigata, Oct., 2003, pp.309-314.

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J10 Abrasive Characteristics on Mirror Finishing by Alumina Fiber Brush Contact Information: Associate Professor Hitoshi SUWABE Department of Mechanical Engineering College of Engineering Kanazawa Institute of Technology 7-1 Ohgigaoka, Nonoichi, Ishikawa 921-8501 Japan Email: [email protected] http:www2.kanazawa-it.ac.jp/mvlab2/ Abstract: This study aims to develop the newly mirror finishing method used the alumina fiber brush. This alumina fiber brush has been used to burr process and has high processing ability. Therefore, this fiber brush can not use to mirror finishing. However, we have found out the possibility of mirror finishing by using peach powder slurry or WA grains slurry. Key Issues of the Work: • Mirror fishing • Alumina fiber brush • High-speed mirror processing Status: On-going Publications of this work: 1. K. Ishikawa, H. Suwabe, Y. Tutae, 2004, Mirror Finishing Characteristics using Alumina

Fiber Brush, Proceedings of JSPE, pp.129-130. 2. K. Ishikawa, H. Suwabe, Y. Tutae, 2003, Mirror Finishing Characteristics using Alumina

Fiber Brush and WA Abrasive Grains, Proceedings of JSPE, pp.255.

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J11 Processing Characteristics of Multi-Wire Saw Using Wire Tool Electrodeposited Diamond Grains

Contact Information: Associate Professor Hitoshi SUWABE Department of Mechanical Engineering College of Engineering Kanazawa Institute of Technology 7-1 Ohgigaoka, Nonoichi, Ishikawa 921-8501 Japan Email: [email protected] http:www2.kanazawa-it.ac.jp/mvlab2/ Abstract: Nowadays, the slicing of large sized silicon ingot is carried through by the multi-wire saw using slurry. But, this slicing method has some problems for workability and productivity. The next coming newly slicing method is requested from users and pays attention to the multi-wire saw used diamond wire tool. The cutting efficiency of this wire tool show ten times cutting speed of multi-wire saw using slurry. Therefore, we have developed new diamond wire sawing system or high speed and high accuracy wire tool. Key Issues of the Work: • Mirror fishing • Alumina fiber brush tool • High-speed mirror processing Status: On-going Publications of this work: 1. K. Ishikawa, H. Suwabe, and K. Oota, 2003, Development of Diamond wire tool using

Twisted Core Wire, Journal of JSAT, pp.495-500 2. K. Ishikawa, H. Suwabe, F. Sakuma And M. Uneda, 2000, A Basic Study on Processing

Characteristics of Diamond Multi-Wire Saw by means of the Workpiece Rotation Type, Proceedings of Advances in Abrasive Technology �, pp.229-232 ．

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J12 Study on Dicing Saw using Ultrasonic Vibration Contact Information: Associate Professor Hitoshi SUWABE Department of Mechanical Engineering College of Engineering Kanazawa Institute of Technology 7-1 Ohgigaoka, Nonoichi, Ishikawa 921-8501, Japan Email: [email protected] http:www2.kanazawa-it.ac.jp/mvlab2/ Abstract: We tried to develop a new processing system using ultrasonic vibration. This processing system has the unique spindle system to generate the ultrasonic vibration. This study aims to evaluate the possibility of hi-speed processing of this newly developed processing machine system using ultrasonic vibration. Key Issues of the Work: • Vibration state of sonic tool • High-speed and high-accuracy processing Status: On-going Publications of this work: 1. K. Ishikawa, H. Suwabe, Y. Tanno, Y. Take, 2004, Study on High-speed Dicing using

Ultrasonic Vibration, Proceedings of ISAAT2004, pp.453-456. 2. K. Ishikawa, H. Suwabe, K. Nokura, M. Uneda, Y. Take, 2002, A Basic Study on

Processing Characteristics of OD-blade Saw Using Ultrasonic Vibration, Proceedings of ASPE, Vol.27, pp.501-504．

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J13 Effect of Cooling Methods on Grinding Temperature Contact: Prof. Takashi Ueda (Address : Japan, Kanazawa 920-8667, Kodatsuno 2-40-20, Faculty of Engineering, Kanazawa University) E-mail : [email protected] Home page : http://www.ms.t.kanazawa-u.ac.jp/~manufac/ TEL : +81-76-234-4724, FAX : +81-76-234-4725 Summary The effect of cooling methods on grinding temperature is investigated experimentally. Supply of air cooled by liquid nitrogen and supply of grinding fluid to the grinding point are employed as a cooling method. The experimental results are compared with those obtained by the grinding with no cooling method (dry grinding). The temperatures of workpiece and cutting grains are measured using an infrared radiation pyrometer with an optical fiber to investigate the effect of cooling methods. In the workpiece temperature, the effect of cooled air does not reach the effect of fluid by far, but it is more effective than dry condition. In the temperature of cutting edge, cooled air is not very effective. The number of cutting edges in cooled air grinding is small compared with that of dry grinding. In surface roughness, the cooled air grinding is greatly superior to the dry grinding but it is inferior to the fluid grinding (wet grinding). By modeling the grinding wheel, the heat transfer coefficient around the grinding point is calculated. The heat transfer coefficient in fluid grinding is much larger than that in cooled air grinding. Status: Completed Key Issues: Publications: 1. Takashi Ueda, Keiji Yamada, Jun’ichi Ishikawa And Akira Hosokawa, Effect of Cooling

Methods on Grinding Temperature, Proceedings of the Progress of Machining Technology, pp.381-387, Sep. 2000.

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http://www.ms.t.kanazawa-u.ac.jp/%7Emanufac/

J14 Evaluation of Grinding Wheel Surface by Means of Grinding Sound Discrimination” Contact: Prof. Takashi Ueda (Address : Japan, Kanazawa 920-8667, Kodatsuno 2-40-20, Faculty of Engineering Kanazawa University Japan E-mail : [email protected] Home page : http://www.ms.t.kanazawa-u.ac.jp/~manufac/ TEL : +81-76-234-4724, FAX : +81-76-234-4725 Summary: This study deals with a new technique of in-situ characterization of the grinding wheel surface for the purpose of optimizing the grinding operation including truing and dressing. As a static evaluation, the protrudent grain height from the bond, depth of chip pocket, successive cutting-edge spacing and radial/circumferential distribution of cutting points are calculated based on the entire grinding wheel profile measured by a stylus profilometer. The micro-morphology and spatial distribution of cutting edges and their change with grinding operation can be measured by means of image processing technique. As a dynamic evaluation, the condition of wheel surface is diagnosed by analyzing the grinding sound and/or vibration of the table, which are generated by the wheel-work interference in grinding. Some specific wheel surfaces are prepared as references by the appropriate truing and/or dressing procedure, and grinding sounds generated by these wheels are discriminated by analyzing the dynamic frequency spectrum by a neural network technique. Then the grinding sound from arbitrarily-dressed wheel is discriminated into the above references. Key Issues: • When using this technique for resinoid-bonded CBN wheels, the wheel has to be trued by

the metal-bonded diamond block truer and then the bond material is removed by dressing with rotary WA-cup so as to make appropriate chip pocket in the range of 10 to 25 µm as references.

• The grinding sound can be discriminated under the appropriate network configuration, provided that the frequency range of 10-15 kHz is analyzed.

Publications: 1. Akira HOSOKAWA, Kazufumi MASHIMO, Keiji YAMADA and Takashi UEDA,

Evaluation of Grinding Wheel Surface by Means of Grinding Sound Discrimination, Proceedings of the International Conference on Leading Edge Manufacturing in 21st Century, pp.243-246, Nov. 2003.

2. Akira HOSOKAWA, Kazufumi MASHIMO, Keiji YAMADA and Takashi UEDA, Evaluation of Grinding Wheel Surface by Means of Grinding Sound Discrimination, International Journal of the Japan Society of Mechanical Engineers, Ser.C, Vol. 47, No. 1, pp.52-58, March 2004.

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J15 Laser Dressing of Metal-Bonded Diamond Wheel Contact: Prof. Takashi Ueda (Address : Japan, Kanazawa 920-8667, Kodatsuno 2-40-20, Faculty of Engineering Kanazawa University Japan E-mail : [email protected] Home page : http://www.ms.t.kanazawa-u.ac.jp/~manufac/ TEL : +81-76-234-4724, FAX : +81-76-234-4725 Summary This study deals with a laser dressing of a metal-bonded diamond wheel as part of a laser conditioning of superabrasive grinding wheels including truing, sharpening and cleaning. A bronze bond diamond stone SD120N75B is chosen as target to be dressed as a first step. Pulsed Nd:YAG laser operating at a wavelength of 1.064 µm is irradiated in order to remove the bond material. The influence of laser power, scanning speed and air assist on bond removal characteristics are investigated and the thermal damages of both bonding material and abrasive grains are also examined. The bond material is partially removed by laser irradiation, in which melting and vaporizing take place. The minimum dressing depth approximately 30 µm, which is appropriate amount for a #120-mesh grinding wheel, is obtained when the laser power Q is 104 W. The depth and diameter of the crater formed by a single-shot pulse decrease with laser power decreases. The shallower crater than a critical depth, however, cannot be formed by reducing the laser power because of the instantaneous re-solidification of the material. Defocusing is also effective in controlling the dressing volume, especially minimize the dressing depth and expand the dressing region per pulse. Key Issues: • It is necessary to spray air on the laser irradiating spot so as to blow away the molten binder

before it solidifies again • Air spray has also an effect on the prevention of thermal damage and deterioration of both

bond and abrasive grains Publications: 1. Akira Hosokawa, Tsutomu Yunoki, Keiji Yamada And Takashi Ueda, Laser Dressing of

Metal-Bonded Diamond Wheel, Proceedings of the ASPE 19th Annual Meeting, Vol.34, pp.530-533, Nov. 2004.

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J16 Working Activity of Cutting Grains in Grinding. Contact: Prof. Takashi Ueda (Address : Japan, Kanazawa 920-8667, Kodatsuno 2-40-20, Faculty of Engineering Kanazawa University Japan E-mail : [email protected] Home page : http://www.ms.t.kanazawa-u.ac.jp/~manufac/ TEL : +81-76-234-4724, FAX : +81-76-234-4725 Summary: In this project, the activity of effective cutting grains in cutting of work and the activity of effective cutting grains in generation of finished surface are investigated. The former was investigated by the measurement of wheel surface temperature immediately after grinding using infrared radiation pyrometer with an optical fiber, and the latter was investigated by the measurement of finished surface roughness using three-dimensional surface roughness tracer, respectively. These activities of cutting grains in the whole circumference of wheel surface were clarified. The results obtained are as follows: 1) Cutting grains which have effective concern with cutting of work certainly act in every rotation of wheel. 2) The number of effective cutting grains in cutting of work increases as wheel depth of cut increases. 3) Cross-sectional shape of scratch toward grinding direction on the finished surface accurately corresponds in the every period of one circumference of wheel in the order of sub-micrometer. 4) Finished surface is generated by some identical cutting grains even when wheel depth of cut increases. Status: Completed Publications: 1. Masahiko SATO and Takashi UEDA, Working Activity of Cutting Grains in Grinding,

Journal of the Japan Society for Precision Engineering, Vol.67, No.11, pp.1850-1855, Nov. 2001.

2. Akira Hosokawa, Kunio Sakuma, Takashi Ueda, Insitu Characterization of Grinding Wheel Surface, ASPE, 20, 99, A102, 1999.

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J17 Application of Air Cooling Technology and Minimum Quantity Lubrication to Relief Grinding of Cutting Tools

Contact Information: Professor Tojiro Aoyama Faculty of Science and Technology Dept. of System Design Eng. Keio University 3-14-1 Hiyoshi, Kohoku-ku Yokohama 223-8522 Japan Tel: +81 45 566 1721 Fax: +81 45 563 2472 Email: [email protected] Abstract: This study focuses on applying the environmentally friendly cooling-air grinding and minimum quantity lubricant (MQL) methods to relief surface tool grinding. The present study is aimed at comparing dry grinding, cooling-air grinding, and MQL to the relief surface grinding process. The combination of cooling-air and MQL grinding is found to perform well and is better than conventional grinding with fluid. The following conclusions were drawn: • for relief surface tool grinding of a specimen (width: 2 mm) with a depth of cut not

exceeding 0.1 mm, the temperature at the grinding point is the same with cooling-air and cooling-air + MQL grinding as oil-based fluid grinding.

• the grinding resistance is nearly proportional to the depth of cut for cooling-air and cooling-air + MQL grinding. Accordingly, these methods can be considered to be suitable, resulting in minimal damage to the grain due to an increase in grinding resistance and minimal grain slippage due to the lubricant effect at the arc of contact between the grinding wheel and workpiece.

• at a depth of cut of 0.05 mm in cooling-air grinding, and 0.05 mm or 0.1 mm in cooling-air + MQL grinding, the surface roughness (within 2.14 u,mRz) was lower than that observed in oil-based fluid grinding.

• hardness did not change with the distance from the ground surface except in the case of dry grinding.

Key Issues of the Work: Status: Ongoing Publications of this work: 1. S. Inoue and T. Aoyama, Application of Air Cooling Technology and Minimum Quantity

Lubrication to Relief Grinding of Cutting Tools, Proc. of Advances in Abrasive Technology VI, ISAAT 2003, Bristol, UK

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J18 Monitoring of the Grinding Process Using Acoustic Emission Sensors Contact Information: Professor Ichiro Inasaki Faculty of Science and Technology Keio University 3-14-1 Hiyoshi, Kouhoku-ku Yokohama-Shi Tel: +81 45 566 1450 Fax: +81 45 566 1452 Email: [email protected] http:www.ina.sd.keio.ac.jp Abstract: This researcher has monitored surface grinding using acoustic emission and electrical power sensors. It was found that the real-time signals could be used to determine the threshold of burn. An adaptive control strategy was developed using Fuzzy Neural Net Control and a new AE sensor-integrated grinding wheel. Key Issues of the Work: • Filtering and analysis of the signals quickly enough for adaptive control • Integrating the software into a commercial PLC Status: Completed 2002 Publications of this work: 1.

2.

3.

B. Karpuschewski, M. Wehmeier, I. Inasaki: Grinding monitoring system based on power and acoustic emission, Annals of the CIRP, Vol.49, No.1, 235-240 (2000). A. Shida, I. Inasaki: Development of Intelligent Monitoring System for Grinding Process, Trans. of the Japan Society of Mechanical Engineers, Vol.65, No.629, 173-178 (1999). I. Inasaki: Intelligent Monitoring System for Grinding, Proc. of the 2nd International Abrasive Technology Conference, Taiwan (1995).

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J19 Effect of Cutting Edge Truncation on the Ground Surface of Hard and Brittle Material for Optical and/or IT Components Contact Information: Professor Jun’ichi Tamaki Department of Mechanical Engineering Kitami Institute of Technology 165 Koencho, Kitami, Hokkaido 090-8507 Japan Email: [email protected] http:nano.mech.kitami-it.ac.jp Abstract: From computer simulation it is found that surface roughness of nanometer order is easy to be generated by cutting edge truncation of a coarse-grained grinding wheel, but the contribution of cutting edge truncation to a decrease in the maximum grain depth of cut is not sufficient to realize ductile-regime grinding so that an appropriate selection of a fine-grained grinding wheel as well as suitable truncation are prerequisite. It is also found from single grit diamond grinding of boro-silicate glass that a critical depth of cut for ductile-regime grinding depends on the rake angle of cutting edges and takes a larger value in up cut grinding than that in down cut grinding. Key Issues of the Work: • Evaluating ductile-regime grinding ability from the viewpoint of cutting edge shape • Exploring the possibility of ductile-regime grinding of optical components Status: On-going Publications of this work: 1. Tamaki, J., Kubo, A., Yan, J., Iyama T., 2004, Study on Effect of Cutting Edge Truncation

on Grinding Mechanism by Computer Simulation, Advances in Abrasive Technology, Vol. 7, pp. 275-281.

2. Tamaki, J., Mahmoud, T., Yan, J., Sato, G., Iyama, T., 2004, Effect of Cutting-Edge Shape on Ductile Regime Grinding of Optical Glass in Single-Grit Diamond Grinding, Key Engineering Materials, Vols. 257-258, pp. 89-94.

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J20 Electro-contact Discharge Dressing of Super-abrasive Grinding Wheel Contact Information: Professor Jun’ichi Tamaki Department of Mechanical Engineering Kitami Institute of Technology 165 Koencho, Kitami, Hokkaido, 090-8507 Japan Email: [email protected] http:nano.mech.kitami-it.ac.jp Abstract: A series of electrocontact discharge dressing (ECDD) of metal-bonded diamond grinding wheel and conductive-resin-bonded cBN grinding wheel have been conducted by using a metal-bonded GC wheel as a rotary electrode. It is found that the minimum grain size of the grinding wheel applicable to the ECDD is limited to 6 to 10 μm and an open-circuit voltage lower than the arc voltage of 20 V with straight polarity should be applied in order to realize a stable discharge pulses. Key Issues of the Work: • Electro discharge dressing of matrix type super-abrasive grinding wheel • Applying an open-circuit voltage lower than gap voltage to realize a spark discharge Status: Completed Publications of this work: 1. Tamaki, J., Kubo, A., Yan, J., Narita, K., 2003, Electrocontact Discharge Dressing of a

Resin-Bonded CBN Grinding Wheel and its Grinding Performance, Key Engineering Materials, Vols. 238-239, pp. 327-332.

2. Kubo, A., Tamaki, J., Sugino, T., Yan, J., Narita, K., 2002, Electro-Contact Discharge Dressing of a Resin-Bonded CBN Grinding Wheel using a Low Open-Circuit Voltage, J. JSAT, Vol.46-7, pp. 348-353.

3. Xie, J., Tamaki, J., Kubo., A., Iyama, T., 2001, Application of Electro-Contact Discharge Dressing to a Fine-Grained Diamond Grinding Wheel, J. JSPE, Vol. 67-11, pp. 1844-1849.

4. Xie, J., Tamaki, J., Kubo, A., Iyama, T., 2001, Dry Electrocontact Discharge Dressing of a Very Fine-Grained Diamond Grinding Wheel, Proc. 2nd Int. Conf. on Design and Production of Dies and Molds.

5. Tamaki, J., Xie, J., Iyama, T., 2000, Electrocontact Discharge Dressing of Very Fine-Grained Diamond Grinding Wheel - Effect of Discharge Polarity-, Advances in Abrasive Technology, Vol.3, pp.391-398.

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J21 Precision Truing of Metal-Bonded Diamond Wheel for Surface Grinding Contact Information: Professor Jun’ichi Tamaki Department of Mechanical Engineering Kitami Institute of Technology 165 Koencho, Kitami, Hokkaido 090-8507 Japan Email: [email protected] http:nano.mech.kitami-it.ac.jp Abstract: In order to realize a wheel profile flatness of submicron order in the truing of a superabrasive grinding wheel for surface grinding, a technique in which the wheel axial profile is given by a straight line enveloped by circular arcs is proposed. This technique has been applied to two type of truing methods: the GC abrasive cup wheel method for a resin-bonded cBN wheel and the electrocontact discharge method for a metal-bonded diamond wheel. It is confirmed from the experiments that the wheel profile flatness less than 0.5 μm can be obtained in both the methods, and the good profile flatness contributes to the improvement of the finished surface roughness in traverse grinding. The excellent truing accuracy of this technique was demonstrated by computer simulation. Key Issues of the Work: • Truing an axial profile of metal-bonded diamond grinding wheel with a flatness of sub-

micron order • Deterministic truing of grinding wheel by means of enveloping method Status: Completed. Publications of this work: 1. Xie, J., Kubo, A., Tamaki, J., Yan, J., 2002, Precision Truing of a Metal-Bonded Diamond

Grinding Wheel by Means of an Envelope Generation Method, J. JSAT, Vol.46-10, pp. 521-526.

2. Tamaki, J., Kubo, A., Xie, J., Yan, J., Iyama, T., 2002, Precision Truing of Superabrasive Grinding Wheel by Means of an Envelope Generation Method, Proc. 3rd euspen Int. Conf., pp. 197-200.

3. Tamaki, J., Sugino, T., Iyama, T., 2000, Effect of Difference in Dressing Method on Grinding Performance of a Metal Bonded Diamond Grinding Wheel, J. JSAT, Vol.44-5, pp. 231-234.

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J22 Three-Dimensional Measurement of Diamond Abrasive Grain and the Modeling of Cutting Edge Shape Contact Information: Professor Jun’ichi Tamaki Department of Mechanical Engineering Kitami Institute of Technology 165 Koencho, Kitami, Hokkaido 090-8507 Japan Email: [email protected] http:nano.mech.kitami-it.ac.jp Abstract: Three-dimensional shape of diamond abrasive grains protruded on a metal-bonded grinding wheel was measured by scanning laser microscope and a technique for modeling cutting edge shape was developed based on noise removal by wavelet analysis and cutting edge detection by morphological processing. It is found from the measurements that the cutting edges can be represented by a triangular cone which has two types of cutting edges, double-faced cutting edge defined by rake angle and wedge angle, and one-faced cutting edge defined by rake angle and face angle. The average of rake angle is 70 deg., the average of wedge angle is 112 deg. and the average of face angle is 111 deg. for SDC270 grits. Key Issues of the Work: • Measuring the three-dimensional shape of diamond abrasive grain by means of Scanning

laser microscope • Noise removal by wavelet analysis and modeling by morphological processing Status: Completed Publications of this work: 1. Mahmoud, T., Tamaki, J., Yan, J., Suzuki, S., 2003, Measurement of Three-Dimensional

Shape of Diamond Grain utilizing a Scanning Laser Microscope, J. JSAT, Vol.47-6, pp. 314-319.

2. Mahmoud, T., Tamaki, J., Yan, J., 2003, Three-Dimensional Shape Modeling of Diamond Abrasive Grains Measured by a Scanning Laser Microscope, Key Engineering Materials, Vols. 238-239, pp. 131-136.

3. Mahmoud, T., Tamaki, J., Suzuki, S., Iyama, T., 2001, Measurement of Three-Dimensional Shape of Diamond Abrasive Grain by Means of Laser Beam Microscope, Advances in Abrasive Technology, Vol. 4., pp. 387-394.

4. Miura, K., Okada, M., Tamaki, J., 2000, Three-Dimensional Measurement of Wheel Surface Topography with a Laser Beam Microscope, Advances in Abrasive Technology, Vol.3, pp.303-308.

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J23 Performance of the Speed-Stroke and Creep-Feed Grinding under Constant Removal Rate

Contact: Prof. S. Okuyama. Dept. of Mechanical Systems Engineering National Defense Academy 1-10-20, Hashirimizu, Yokosuka Kanagawa 239-8686, Japan TEL: 468-41-3810 (Ex. 2467) FAX: 468-44-5900 E-mail: [email protected] Abstract: A surface-grinding machine with a linear motor driven table and a high-speed spindle has been developed. The table speed can be changed from 1mm/min to 100m/min and an achieved acceleration is 19.6m/s2. The maximum peripheral speed of the 200mm diameter wheel is 200m/s. This work examines the grinding performance for chromium molybdenum steel (SCM440) under speed-stroke grinding characterized by a high table speed with a small depth of cut and creep-feed grinding characterized by a low table speed with a large depth of cut. The performance of each grinding method is compared under a constant material removal rate of 100 mm3 /mm.s. It was confirmed that the advantage of the speed-stroke grinding is a lower grinding force and less temperature rise at a grinding zone. On the other hand, the advantage of the creep-feed grinding is a higher grinding ratio and smaller surface roughness. In addition, a higher wheel peripheral speed results in lower grinding force, higher grinding ratio and smaller surface roughness. Status: Current Publications of the Work: 1. Yui, S. Okuyama, T. Kitajima, 2003, Performance of the Speed-Stroke and Creep-Feed

Grinding under Constant Removal Rate, 6th International Symposium On Advances In Abrasive Technology (ISAAT), Bristol, England

2. Yui, S. Okuyama, T. Kitajima, and K. Kosugi, ASPE Annual Meeting, pp. 445., 2001

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http://us.f815.mail.yahoo.com/ym/[email protected]

J24 Control of a Machine-Table Reciprocation Using a Hydrophone Contact: Prof. S. Okuyama. Dept. of Mechanical Systems Engineering National Defense Academy 1-10-20, Hashirimizu, Yokosuka Kanagawa 239-8686, Japan TEL: 468-41-3810 (Ex. 2467) FAX: 468-44-5900 E-mail: [email protected] Abstract The machining efficiency of surface grinding is not sufficient due to the over travel of the machine table. In order to minimize the over travel, a new table-reciprocation-control system is developed and its performance is experimentally investigated. During grinding, acoustic signals are emitted from the contact zone between the grinding wheel and the workpiece, and they radically diminish when the wheel departs the workpiece. The developed system sends a command which reverses the table motion when the acoustic level falls below a trigger level. By using the proposed system, over travel of the machine table is minimized. The researchers have also developed a wheel-to-workpiece contact prediction system using a hydrophone and have investigated its performance. The results showed the acoustic power change is more significant under the conditions of smaller grinding fluid flow, higher grinding wheel speed and higher wheel porosity. This acoustic change can be used for the positioning of the grinding wheel. When the acoustic-power exceeds a certain level, a trigger signal is sent to the NC system to stop the wheel approach. By using this system, the grinding wheel can be automatically positioned 20 to 100μm before wheel-to-workpiece contact under the approaching speed of 1mm/min.

Key Issues with this Work: • Improvement in S/N ratio of the sound level and system reliability; Application to super-

abrasive wheels Publications of this Work: 1. Yui, S. Okuyama, and T.Kitajima, 2004, Control of a Machine-Table Reciprocation Using a

Hydrophone, 7th International Symposium on Advances in Abrasive Technology (ISAAT),Bursa, TURKEY- June 17-19

2. Yui, S. Mototani, S. Okuyama And T. Kitajima, 2003, Prediction of Contact between Grinding Wheel and Workpiece-Clearance Prediction by Using Hydrophone, EUSPEN, Aachen, Germany

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J25 Theoretical Study on the Effect of Form Error of a Grinding Wheel under Free-Form Grinding

Contact: Prof. S. Okuyama. Dept. of Mechanical Systems Engineering National Defense Academy 1-10-20, Hashirimizu, Yokosuka Kanagawa 239-8686, Japan TEL: 468-41-3810 (Ex. 2467) FAX: 468-44-5900 E-mail: [email protected] Abstract. Free forms can be efficiently generated through the three-dimensional motion of a grinding wheel with round-off. In this method, however, form error of the grinding wheel directly affects machining accuracy. The effects of form deviation of the wheel surface on form error of the generated shape, ER, have been investigated through computer simulation, where the wheel surface is assumed to have waviness with amplitude a, and wave length, λ. The main results obtained are as follows: duplication ratio, ER/2a, is a function of and Rg/Rw, where Rg and Rw are curvature radii of the grinding wheel and workpiece surface respectively; the longer λ is or the smaller a is, the larger the duplication ratio becomes; when λ and a are constant, the grinding wheel with large curvature radius is suitable for precision machining of convex surfaces; and form deviation of the wheel surface must be smaller than the objective machining accuracy when it is within a sub-micrometer.

)/(2 Rga ⋅λ

Key issues with this Work: • Experimental certification of the theoretical results Status: Ongoing Publications: 1. S.Okuyama, T.Kitajima A.Yui, 2003, Theoretical Study on the Effect of Form Error of a

Grinding Wheel Under Free Form Grinding, 6th International Symposium On Advances In Abrasive Technology (ISAAT), Bristol, England

365


J26 Theoretical Study on the Wheel-Wear Removal and Errors using the new Round-Off-Truing Method

Contact: Prof. S. Okuyama. Dept. of Mechanical Systems Engineering National Defense Academy 1-10-20, Hashirimizu, Yokosuka Kanagawa 239-8686, Japan TEL: 468-41-3810 (Ex. 2467) FAX: 468-44-5900 E-mail: [email protected] Abstract : The Researcher previously proposed the new round-off-truing method for free-form grinding and confirmed the effectiveness of the proposed method. However, machine operators have to re-true the grinding wheel at certain intervals to eliminate wheel wear. In this report, a computer simulation has been performed to clarify the effectiveness of the proposed method for eliminating wheel wear. A wear-flat generated on the wheel surface can be efficiently removed by this method when the truing-wheel wear ratio has a small value. A cosine-shaped undulation due to wheel wear can also be efficiently removed when both the truing ratio and wavelength of the undulation have small values. In addition, the effects of geometrical and motion factors, wear ratio of the truing wheel, etc. on the truing accuracy, were examined using computer simulations. Form error increases with the axial play of a brake-truer spindle, but it is not affected by the set up error in the direction of the grinding wheel spindle Issues with this Work: • Development of a perfectly homogeneous and hard-to-ware truing wheel, Experimental

certification of the theoretical results Publications: 1. S.Okuyama, T.Kitajima, and A.Yui, 2004, Theoretical Study on the Wheel-Wear Removal

Using The New Round-Off-Truing Method, 7th International Symposium on Advances in Abrasive Technology (ISAAT), Bursa, TURKEY

2. Kitajima, T., Okuyama, S., Yamashita, K. And Yui, S., 2003, Study On The Round-Off Truing Method Using Circular Motion - Truing Of A Superabrasive Wheel With A Homogeneous Truing Wheel, 6th International Symposium On Advances In Abrasive Technology, Bristol, England.

3. Kitajima, et al., 2002, Study on The Machining Accuracy of Round-Off Truing Method - Experimental Analysis of Error Factors, ASME annual meeting

4. T.Kitajima, et al., 2001, Study on the Machining Accuracy of the Round-off Truing Method -Theoretical Analysis of Error Factors, 4th International Symposium on Advances in Abrasive Technology (ISAAT), Seoul, November 6-9

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J27 Influence of the Static Stiffness of Grinding System on the Generation of Affected Layers Contact Information: Prof. S. Yokoyama Department of Mechanical Engineering College of Science and Technology Nihon University 1-8-14 Kanda-Surugadai Chiyoda-Ku, Tokyo 101-8308 Japan Email: [email protected] Abstract: Relationship between the static stiffness of grinding system and the depth of surface affected layers generated in a grinding operation is experimentally investigated. A method to realize grinding without any surface affected layers is proposed. The influence of static stiffness on grinding force is considered. It is confirmed that the surface affected layers are generated during an infeeding process, in which a large grinding force is involved. The layers are then removed in a spark-out process. According to this, it is clear that, if the elastic deformation is utilized effectively, the surface affected layers can be removed in the spark-out process. Since grinding force is independent from the stiffness of a grinding system, it has been considered that the affected layers are also independent from the stiffness of the system. In this study, the influence of the grinding system stiffness on the depth of surface affected layers is experimentally investigated. It is found that the surface affected layers generated during an infeeding process can be removed during a subsequent spark-out process by utilizing the elastic deformations. This effect is significant when the stiffness is low. Status: Ongoing Publications of this work: 1. S. Yokoyama, M. S. Lee and T. Yamada, Influence of the Static Stiffness of Grinding

System on the Generation of Affected Layers, 6th International Symposium on Advances In Abrasive Technology (ISAAT), Bristol, England

367

J28 Analysis of the Cam Grinding Mechanism with a CNC Cam Grinder Contact Information: T. Fujiwara Cooperative Research Center Okayama University 5302 Haga, Okayama 701-1221, Japan Email: [email protected] Abstract: In this study, the plunge grinding process of CNC cam grinding is analyzed, and the control method of the workpiece rotational angle speed is investigated with numerical simulation. Main conclusions obtained are as follows: (1) The horizontal travel speed of the wheel head can be analyzed. (2) In order to establish the precision cam grinding method, the controlled normal force grinding method, the controlled surface finish grinding method and the controlled speed ratio grinding method are proposed and the grinding performance can be investigated by simulation. (3) It is made clear that the optimum setting of both the workpiece rotational angle velocity and the horizontal travel speed (federate) of the wheel head provide stable grinding results. Status: Ongoing Publications of this work: 1. T. Fujiwara and S. Tsukamoto, Analysis of the Cam Grinding Mechanism with a CNC Cam

Grinder, Proc. of Advances in Abrasive Technology VI Conf., ISAAT 2003, Bristol, UK. 2. T. Nakajima, S. Tsukamoto, Y. Masuda and K. Sato: Journal of the Japan Society for

Precision Engineering, Vol. 53 (1987), p. 820.

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J29 Molecular Dynamics Analysis of Material Removal Processes Contact Information: Professor Shoichi Shimada Department of Mechanical Engineering Osaka Electro-Communication University 18-8, Hatsu-cho, Neyagawa, Osaka 572-8530 Japan Email: [email protected] Abstract: By the molecular dynamics simulations, it is predicted that an ideal surface processing for minimal surface roughness and subsurface damage is ductile-mode grinding to generate desired surface configuration and following mechano-chemical polishing to remove subsurface damage layer. Key Issue of the Work: Atomic scale analysis of material removal process Status: Ongoing Publications of this work: 1. H. Tanaka, S. Shimada, N. Ikawa: An Ideal Surface Processing of Monocrystalline Silicon

for Minimal Surface Roughness and Damage Predicted by Molecular Dynamics Analysis, Advances in Abrasive Technology VI, ISAAT, 2002.

2. N. YASUNAGA, J. TAMAKI, K. Suzuki, T. Uematsu, Proc. The 3rd International Symposium on Advances in Abrasive Technology, Honolulu, U.S.A., pp.205-210, 2000.

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J30 Development of a Resinoid Diamond Wire Containing Metal Powder for Slicing Ingots Contact Information: Associate Professor Toshiyuki ENOMOTO Department of Computer-Controlled Mechanical Systems Graduate School of Engineering Osaka University 2-1, Yamada-oka, Suita, Osaka, 565-0871 JAPAN Tel: +81-6-6879-7340 Fax: +81-6-6879-7247 Email: [email protected] Abstract: Loose-abrasive wire sawing widely employed for slicing silicon ingots has problems of dirty working environment and inefficiency. Fixed-abrasive wires, namely electroplated diamond wires and resinoid diamond wires, have been developed to overcome these problems. Resinoid diamond wires, which can be produced at a lower cost, can be put to practical use, but they have a low breaking twist strength. In this study, metal powder is added to the resinoid bond to strengthen it. A series of experiments revealed that the breaking twist strength, heat resistance, tool wear resistance, and slicing efficiency of this wire are significantly improved. The following conclusions were drawn from the evaluations of the physical characteristics and slicing performance: • During the heat-curing process of the bonding resin, blue brittleness occurs in the core wire

and the breaking twist strength of the core wire deteriorates considerably • Adding copper powder to the bonding resin for the resinoid wire improves breaking twist

strength • Adding copper powder to the bonding resin for the resinoid wire also improves the

resistance to heat • The resinoid wire containing metal powder is superior to the resinoid wire without powder

in several points. The slicing performance was improved by 1.7 times and the amount of tool wear was 40% less

• Better surface roughness (3.4 μm Ry, 0.5 μm Ra) is obtained when slicing with a resinoid diamond wire, irrespective of whether copper powder is added, than is obtained when slicing with an electroplated wire.

Key Issues of the Work: • Development of a resinoid diamond wire tool having good physical characteristics and

slicing performances Status: Completed Publications of this work:

1. T. Enomoto, Y. Shimazaki, Y. Tani, M. Suzuki and Y. Kanda, Development of a Resinoid Diamond Wire Containing Metal Powder for Slicing a Slicing Ingot, Annals of CIRP, Vol. 48/1/1999, pp. 273-276.

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J31 Nanoprecision Micro-mechanical Fabrication Contact Information: Hitoshi Ohmori RIKEN Japan Tel: +81 48 462 1111 Fax: +81 48 462 4637 Email: [email protected]: http://www.nexsys.ne.jp/ Abstract: The main objective of our research is the development of revolutionary and new material processing technologies in grinding, lapping, polishing, cutting and forming for an extensive range of materials. Through advanced research activities on ultraprecision, nanoprecision and ultra-smooth machining processes mainly by ELID grinding invented by Ohmori, required for the fabrication of advanced functional devices such as optical and electronic components, we launched the research of a new field of micro-mechanical fabrication technologies by our original desktop fabrication systems in addition to surface functional modification, measurement and evaluation techniques, aiming at a wide variety of materials, and precision and scale ranging from micrometer to nanometer level, to meet practical and applied industrial needs. Key Issues of the Work: (1) Nanoprecision mechanical fabrication processes for micro-structural/functional devices (2) Applications on micro-fabrication processes (3) Forming Processes/tribological investigations under micro to nano-scale (4) Computational mechanics of materials forming processes Status: in progress Publications of this work: 1. Ohmori H., and Nakagawa T.: “Mirror Surface Grinding of Silicon Wafer with Electrolytic

In-process Dressing”, Annals of the CIRP, Vol.39, No.1, pp.329-332 (1990). 2. Ohmori H., and Nakagawa T.: “Analysis of Mirror Surface Generation of Hard and Brittle

Materials by ELID (Electrolytic In-Process Dressing) Grinding with Superfine Grain Metallic Bond Wheels”, Annals of the CIRP, Vol.44/1, pp.287-290 (1995).

3. Ohmori H., and Nakagawa T.: “Utilization of Nonlinear Conditions in Precision Grinding with ELID (Electrolytic In-Process Dressing) for Fabrication of Hard Material Components”, Annals of the CIRP, Vol.46/1, pp.261-264 (1997).

4. Ohmori, H., Ebizuka, N., Morita, S., and Yamagata, Y.: "Ultraprecision Micro-Grinding of Germanium Immersion Grating Element for Mid-Infrared Super Dispersion Spectrograph", Annals of the CIRP 50, 221-224 (2001).

5. Ohmori, H., Katahira, K., Nagata, J., Mizutani, M., and Komotori, J.: "Improvement of Corrosion Resistance in Metallic Biomaterials using a New Electrical Grinding Technique", Annals of the CIRP 51, 491-494 (2002).

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J32 Grinding Characteristics of Difficult-To-Grind Metals in Cool-Air Grinding by CBN Wheel

Contact Information: Professor Takeshi Tanaka Ritsumeikan University 1-1-1 Nojihigashi, Kusatsu Shiga 527-8577 Japan Email: [email protected] Abstract: This paper describes the usefulness of a non-freon cool-air supply system in the grinding of difficult-to-grind metals by cBN wheel as well as the grinding characteristics of wet, dry, dry-air and cool-air grinding. A lower grinding surface temperature, about 30 K, was obtained in cool-air grinding than that of dry and dry-air grinding. The grinding forces in cool-air grinding were lower than those in dry and dry-air grinding, and at the small wheel depth of cut, they were lower than those in wet grinding. Other observations were: • the differences of grinding forces among the four circumstances were especially remarkable

during the grinding of titanium and inconel 718. • the least surface roughness was obtained through cool-air grinding than through wet, dry and

dry-air grinding of S25C and pure iron. • the SEM observation showed that rather smooth surfaces were obtained, without chip

adherence or plowing, on cool-air ground workpieces. • these grinding characteristics indicate the effectiveness of cool air in grinding difficult-to-

grind metals.

Key Issues of the Work Status: Completed Publications of this work: 1. T. Tanaka, Y. Isono, S. H. Truong, Y. Yoshida, Y. Morisada, New Development of Non-

Freon Cool Air Supply System and Its Application to Cool Air Grinding, The Fifth International Conference on Progress of Machining Technology (ICPMT 2000), Beijing, China.

2. S. H. Truong, Y. Isono, T. Tanaka, Investigation on Thermal Changes of Workpiece in Cool Air Grinding with Porous Metal Bonded Diamond Wheel, J. of JSPE, 66, 12 (2000) 1911.

3. T. Tanaka, Y. Isono, Y. Morisada, Grinding Characteristics of Inconel718 in Cool-Air Grinding, J. of JSAT, 45, 10 (2001) 490 (in Japanese).

4. T. Tanaka, Y. Morisada, Cool-Air Grinding Characteristics of Ductile Materials by CBN Wheel, The Seventh International Symposium on Advances in Abrasive Technology (ISAAT2004) 331, Bursa, Turkey.

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J33 Some Effects of Over Coated Metal for the Mechanical Property Improvement of Bond Bridge of Porous Metal Bonded Diamond Wheel

Contact Information: Professor Takeshi Tanaka Ritsumeikan University 1-1-1 Nojihigashi, Kusatsu Shiga 527-8577 Japan Email: [email protected] Abstract: Bond bridges of Porous Metal Bonded Diamond Wheel (PMBDW) were set up by sintering Ni-Cu-Sn coated grains in the vacuum furnace. The mechanical properties of the bond bridge including the bending strength, shearing strength, and elastic modulus have been improved by the phosphorating treatment, the second heat treatment and the subzero treatment. However, because the metal compound of the bond bridges is still phosphor bronze, their mechanical properties are limited. The researchers try to improve them by diffusing some high-strength metals into the bond bridges. These metals will make an alloy with Cu and Sn, change the metal composition and crystalline structure of the bond bridges and impart their strength to the bond bridge alloy. This abstract describes some effects of over coated metal for the improvement of the strength of the bond bridges. From experiments and discussion, the researchers can make the following conclusions: • The presence of Co and Ni in the bond bridges of the Porous Metal Bonded Diamond Wheel

is essential to increase their mechanical strength. • The mechanical strength of the bond bridges does not increase more, if the quantity of over

coated metal is too much or little. Key Issues of the Work: Status: Completed Publications of this work: 1 T. Tanaka: Development of the Bridged and Pored Type of Metal Bond Diamond Wheel,

J. of JSPE, 57, 9 (1991) 1573 (in Japanese). 2 T. Tanaka: New Development of Metal Bond Diamond Wheel with Pore by the

Growth of Bonding Bridges, Int. J. of JSPE, 26, 1, Mar. (1992) 27. 3 T. Tanaka and Y. Isono: Influences of Metal Constituents to the Characteristics

and Grinding Abilities of Metal Bonded Diamond Wheel, J. of Material Processing Technology, 63 (1997) 175.

4 S.H. Truong, Y. Isono and T. Tanaka: A Study on the Toughening of Bond Bridge of Ni-Cu-Sn Alloy-Development of Porous Metal Bonded Diamond Wheel, J. of JSPE, 64, 6 (1998) 923 (in Japanese).

5 S.H. Truong, Y. Isono and T. Tanaka: A Trial of Bond Bridge Formation with Extracted Metals from Colloidal Solution, Int. J. of JSPE, 33, 1, Mar. (1999) 40.

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J34 New Technologies for Aspherical Grinding/Polishing of Micro/Meso Optics Contact Information: Prof. Tsunemoto Kuriyagawa Nano-Precision Mechanical Fabrication Laboratory Department of Nanomechanics Tohoku University Aramaki Aoba 6-6-01, Aoba-ku, Sendai 980-8579, Japan Tel: +81-22-217-6948, Fax: +81-22-217-7027 E-mail: [email protected]://pm.mech.tohoku.ac.jp/21COE/Kuriyagawa_e.htm Abstract: This paper deals with new technical trends in aspherical generation for micro/meso optical parts. New technologies for ultra-precision aspherical grinding and polishing of aspherical optical lenses and molding dies are introduced. They are a parallel grinding method and a fluctuation-free grinding method. A fluctuation-free ultra-precision aspherical surface generation system was developed to achieve these methods, and demonstrated excellent grinding results of high form accuracy of 25 nm, and ultra-smooth and uniform surface roughness of several nmRy. Furthermore, electrorheological fluid assisted micro-polishing is also introduced. Publications of this Work: 1. M. Saeki, T. Kuriyagawa and K. Syoji, "Machining of Aspherical molding Dies Utilizing

Parallel Grinding Method", J. of JSPE, 68, 8,1067-1071 (2002). [in Japanese] 2. M. Saeki, T. Kuriyagawa, N. Yoshihara, W.K. Chen and K. Syoji, "Study of Parallel

Grinding Method for Aspheric Optical Elements", Proc. Of Int. Conf. on Leading Edge Manufacturing in 21" Century (JSME), 49-54 (2003)

3. T. Kuriyagawa, N. Yoshihara, M. Saeki and K. Syoji, "Nano-Topography Characterization of Axi-symmetric Aspherical Ground Surfaces", Key Engineering Materials, 238,125-130 (2003).

4. T. Kuriyagawa et al., "Micro Truing/Dressing for Small-Sized Aspherical Mirror Grinding", Advances in Abrasive Technology, 4, 111-114 (2001).

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J35 Development of Mechanochemical BaCO3 Pellets Bonded by Soft Binders Suitable for Damage-free Polishing of Si Wafers

Contact Information: Professor Yasunaga Dept. of Engineering University of Tokai 1117 Kitakaname Hiratsuka Kanagawa Japan phone: 81-463-58-1211 fax :81-463-59-8150 e-mail:[email protected] Abstract: It is known that Si wafers can be mechanochemically polished with BaCO3 pellets bonded by phenol- and epoxy-resin. These kinds of resinous binder, however, sometimes leave undesirable micro-scratches on the polished Si surfaces because of thermal hardening of the resin material during polishing operation. In order to avoid generations of these damages, various kinds of soft powder usually used for cooking were tried as the new binder. BaCO3 pellets bonded by soybean flour showed the most excellent polishing performance leaving very smooth surface roughness and no mechanical damage. Mechanochemical BaCO3 pellets have been formed by using natural powder as the binder. The results obtained were (1)BaCO3 pellets bonded by soybean flour and binder-free pellets brought more excellent efficiency and surface feature than the pellets bonded by conventional epoxy-resin, suggesting possibility of practical usage, although the polishing ratios should be more improved, and (2)other pellets bonded by starch, weak flour, strong flour, agar and gelatin showed also good surface features but with less efficiency. Key Issues of the Work: Status: Completed Publications of this Work: 1. Yasunaga, Development of Mechanochemical BaCO3 Pellets Bonded by Soft Binders

Suitable for Damage-free Polishing of Si Wafers, 3rd International Symposium on Advanced Abrasive Technology (ISAAT), 2000, Hawai

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J36 Influence of Machine Tool Stiffness on Fixed-abrasive Planarization Contact Information: Professor Zhou Libo System Engineering Department. Ibaraki University Nakanarusawa 4-12-1, Hitachi Japan 316-8511 TEL/FAX (+81)-294-38-5217 Email: [email protected] http://pel.dse.ibaraki.ac.jp/ Abstract: The motivation of this work is to understand the effects of tool property and downfeed (or infeed) method on the planarization of a patterned Si wafer, for polishing and fixed abrasive processes. In oxide or interlevel dielectric (ILD) planarization process, the major concerns are the global planarity, oxide thickness differences in different regions across the chip and the remaining local step height (or height differences in oxide over the patterned features and between pattered features). By extending the MIT density-and-step height dependent model, this study aims to establishing an analytical model to incorporate the tool stiffness and infeed scheme. A 3D simulation has also been performed to show the model validity and the effects of tool stiffness and infeed scheme on the planarity of wafer. Key Issues of the Work: Status: Ongoing Publications of this Work: 1. Libo Zhou, Jun Shimizu and Hiroshi Eda, Effects of Tool Stiffness and Infeed Scheme on

Planarization (Integrated model for simulation of planarization process), International Journal of Manufacturing Technology and Management, (submitted 2004)

2. L. Zhou. H. Ohkubo, J. Shimizu and H. Eda, Simulation on Planarization Process of Device Wafer, Proceedings of ISAAT 2004, June, Bursa/Turkey, pp.393-396

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J37 Ultra Precision Grinding of Micro Aspherical Surface – Development of a Three-Axes Controlled Single Point Inclined Grinding Method

Contact Information: Assoc.Prof. Hirofumi Suzuki Dep. of Mechanical Engg.,Kobe Univ. 657-8501 Rokkoh, Nada Kobe city, 657-8501, Japan Tel & Fax: +81 78803-6149 Tel & Fax: +81 78803-6154 (alternative) E-mail:[email protected]://www.mi-4.mech.kobe-u.ac.jp/ja/index-j.html

Abstract: The needs of digital devices increase rapidly in recent years, and the demand for a micro axis-symmetric aspherical glass lens of large NA (numerical aperture) is expanding rapidly especially in the device for digital camera, camera-equipped mobile phone, DVD pick-up and the optical transmission. The glass lenses are manufactured by glass molding method by using ceramics dies such as tungsten carbide or silicon carbide. The author has successfully to develop inclined grinding method, and micro aspherical shape has been obtained. In previous researches the grinding system in which grinding wheel axis was 45 degrees inclined from workpiece rotational axis was developed. The grinding spindle was an air bearing and the maximum rotational rate of grinding wheel was 15×104min-1. The grinding head was actuated by two-axes (X, Z) drives, the wheel center point was calculated numerically by using Newton-Raphson method. This system was suitable for grinding micro aspherical surfaces and a form accuracy of about 0.1 μm (P-V) was obtained. The improvement of the form accuracy will be required because the specifications of micro lenses become more and more strict in future. However, the shape correction cannot be done satisfactorily, because the wheel wear is not even and the grinding point on the wheel moves. In this paper, a new grinding method is proposed to solve the above problems. In this method, three-axes (X, Y, Z) are controlled simultaneously so that the position of the grinding point on the diamond wheel is fixed. Then the grinding system was developed and grinding experiments of using tungsten carbide micro dies were carried out. In the micro aspherical grinding experiment, the form accuracy of 0.09 μm (P-V) was obtained. After 200 grinding passes (correspond to the finish grinding of 20 dies), the form accuracy was about 0.2 μm (P-V) in the proposed method and about 1.3 μm (P-V) in the conventional method. It can be seen that there is a flat area in the wheel tip in the proposed method. From the experiments it was clarified that this proposed method was effective. Status: Current Publications of this Work: 1. H. Suzuki, et al., Ultra Precision Grinding of Micro Aspherical Surface – Development of a

Three-Axes Controlled Single Point Inclined Grinding Method, Proceeding of ASPE 2004 (Orlando, FL, USA)

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J38 Precision Grinding of Micro Aspherical Surface Contact Information: Assoc. Prof. Hirofumi Suzuki Dep. of Mechanical Engg.,Kobe Univ. 657-8501 Rokkoh, Nada Kobe city, 657-8501 Japan Tel & Fax: +81 78803-6149 Tel & Fax: +81 78803-6154 (alternative) E-mail:[email protected]://www.mi-4.mech.kobe-u.ac.jp/ja/index-j.html

Abstract: Recently, micro-aspherical glass lenses are required for electric devices, optical devices and advanced optical fiber transmission equipments. The glass lenses are manufactured with glass molding method by using ceramics dies such as tungsten carbide and therefore molding dies are most important. The ceramics molding dies must be ground ultra-precisely with micro diamond wheel. In this report, our developed micro grinding methods/systems are discussed according to a variety of the workpiece shapes. Key Issues of the Work: • Micro aspherical grinding • Micro diamond wheel Status: Current Publications of this Work: 1. H. Suzuki, et al., Ultra Precision Grinding of Micro Aspherical Surface – Development of a

Three-Axes Controlled Single Point Inclined Grinding Method, Proceeding of ASPE 2004 (Orlando, FL, USA)

2. H. Suzuki, et al., Precision grinding of micro-aspherical surface, Proceedings of SPIE Vol. TD02 (Rochester, USA),(2003) 1-3.

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J39 Development of a Fixed-Abrasive Tool Utilizing Agglomerative Superfine Abrasives Contact Information: Associate Professor Toshiyuki ENOMOTO Department of Computer-Controlled Mechanical Systems Graduate School of Engineering Osaka University 2-1, Yamada-oka, Suita, Osaka, 565-0871 JAPAN Tel: +81-6-6879-7340 Fax: +81-6-6879-7247 Email: [email protected]: Abstract: In the finishing process of optical glass, polishing with ceria, silica or zirconia slurry is conventionally adopted. The machining process, however, has problems involving inefficiency and a detrimental impact on the environment. Therefore, it is strongly recommended that the process be replaced with fixed-abrasive machining, but conventional fixed-abrasive tools have problems relating to low finishing efficiency or low finished-surface quality. In this study, a lapping film utilizing agglomerative superfine zirconia abrasives is introduced to overcome the above-mentioned problems. The finishing experiments for optical glass BK7 revealed that the surface quality obtained was as good as that obtained by polishing with ceria slurry, while the finishing efficiency was much higher. Furthermore, the possibility to achieve excellent surface quality with high removal rate in large-diameter workpieces is also verified from the results of 200 mm P-TEOS finishing. Key Issues of the Work: • Development of agglomerative superfine abrasives • Development of a lapping film utilizing agglomerative superfine abrasives Status: On-going Publications of this work: 1. T. Enomoto and J. Zhang, Development of a Lapping Film Utilizing Agglomerative Fine

Abrasives for Finishing of Optical Glass, Proceedings of 17th Annual Meeting of the American Society for Precision Engineering, 2002, pp.657-660.

2. J. Zhang, H. Endo and T. Enomoto, A New Lapping Film with Agglomerative Super Fine Abrasives for Large-Diameter Workpiece Surface Finishing, Proceedings of 18th Annual Meeting of the American Society for Precision Engineering, 2003, pp.591-594.

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J40 Mechanical-Chemical Finishing Using a Grinding Stone Including Microcapsules Contact Information: Associate Professor Toshiyuki ENOMOTO Department of Computer-Controlled Mechanical Systems Graduate School of Engineering Osaka University 2-1, Yamada-oka, Suita, Osaka, 565-0871 JAPAN Tel: +81-6-6879-7340 Fax: +81-6-6879-7247 Email: [email protected]: Abstract: A grinding stone that produces a mirror finish on sticky soft metals, such as aluminium, is strongly required. Then we examined the application of tribochemical reaction of perfluoropolyether oil to the finishing. However, because the lubricity of the oil was too high, the removal motion of the stone could not be generated when the oil was supplied. The oil was therefore introduced into the stone in a capsulated form in order to supply it in very small quantities just to the grinding point. Grinding experiments confirmed that the fluoride having good machinability was generated on the surface of aluminium. These experiments demonstrated that the tribochemical reaction between the oil and the surface significantly improved the finishing efficiency and the surface quality of the aluminium disk, as well as silicon wafer. Key Issues of the Work: • Applying tribochemical reaction of perfluoropolyether oil finishing aluminium disks and

silicon wafers • Development of a grinding stone including microcapsules Status: Completed Publications of this work: 1. T. Enomoto, Y. Shimazaki, Y. Tani, K. Etoh, H. Higurashi, Y. Yamaguchi and Y. Sakai,

Mechanical-Chemical Finishing Using a Lapping Stone Including Microcapsules, Proceedings of 1st International Conference of the European Society for Precision Engineering and Nanotechnology, 1999, pp. 218-221.

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J41 Development of Ultra-High Speed Surface Grinding Machine Contact Information: Prof. Tsunemoto Kuriyagawa Nano-Precision Mechanical Fabrication Laboratory Department of Nanomechanics Tohoku University Aramaki Aoba 6-6-01, Aoba-ku Sendai 980-8579, Japan Tel: +81-22-217-6948 Fax: +81-22-217-7027 E-mail: [email protected]://pm.mech.tohoku.ac.jp/21COE/Kuriyagawa_e.htm Abstract: This abstract describes the development of an ultra-high speed grinding (UHSG) machine which is capable of 400m/s wheel speed. UHSG is one of the high efficiency machining methods. It has reached the stage where it can complete well with respects to machining efficiency even in comparison with a cutting method. Concept of the UHSG is not new, however a practical application of the UHSG was difficult due to the manufacturing problems of a grinding wheel and a wheel spindle unit in the ultra-high speed rotation. In previous work, an ultra-high speed spindle unit (30,000 rpm, 22kW, 2×106 dn-value) was developed. In this latest work, a UHSG machine using the spindle unit was designed and manufactured. Vibration, noise and coolant friction loss of the machine were measured and compared with the conventional grinding results. The UHSG tests were performed under the 300m/s wheel speed using the developed machine and a vitrified bonded CBN wheel. The CBN wheel having a CFRP core was specially designed. However, coolant supply was not enough in the region of the UHSG, therefore the development of a low friction supplying method is needed Key Issues with this Work: Status: Ongoing Publications of this work: 1. K. Syoji, N. Yamazaki, R. Watanabe and T. Kuriyagawa, Influence of Wheel Surface Speed

on Grindability of Grinding Material - Studies on Ultra-High Speed Grinding（3rd Report, J

of JSPE (Japan Society of Precision Engineering), 66, 7 (2000), 1145-1149） 2. K. Syoji, T. Kuriyagawa, et al., Development of Ultra-High Speed Surface Grinding

Machine-Studies on Ultra-High Speed Grinding (2nd Report), J of JSPE (Japan Society of Precision Engineering), 63, 4 (1997), 560-564.

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J42 Influence of Wheel Surface Speed on Grindability of Grinding Material Contact Information: Prof. Tsunemoto Kuriyagawa Nano-Precision Mechanical Fabrication Laboratory Department of Nanomechanics Tohoku University Aramaki Aoba 6-6-01, Aoba-ku Sendai 980-8579, Japan Tel: +81-22-217-6948 Fax: +81-22-217-7027 E-mail: [email protected]://pm.mech.tohoku.ac.jp/21COE/Kuriyagawa_e.htm Abstract: This abstract describes the characteristics of an ultra-high speed grinding and the influence of wheel surface speed V on a grindability of the grinding material. The grindability can be estimated by the Cp value that is product of C and p, where C is plowing coefficient of the material and p is the normal pressure acting onto each cutting grain. The Cp value represents a plowing energy for a unit volume of the material, i.e. a specific grinding energy, and can be calculated from the normal grinding force Fn under the condition of constant v/V value (v: workpiece speed) in various wheel depth of cut Δ. In the experiment, an ultra-high speed grinding machine was used, whose maximum wheel surface speed was 400 m/s. The change of the grindability of the material by the increase of wheel surface speed was recognized through the grinding tests using cast iron workpieces under the condition of V = 30 – 300 m/s. The main results obtained are as follows: (1) Cp value increases with an increase of V on shallow grinding conditions. (2) Cp value decreases with an increase of V on high-efficiency conditions. This tendency becomes more remarkable at the larger Δ under a constant v/V value. (3) Wheel wear decreases as the wheel surface speed V increases. Key Issues with this Work: Status: Ongoing Publications of this work: 1. K. Syoji, N. Yamazaki, R. Watanabe and T. Kuriyagawa, Influence of Wheel Surface Speed

on Grindability of Grinding Material - Studies on Ultra-High Speed Grinding（3rd Report, J

of JSPE (Japan Society of Precision Engineering), 66, 7 (2000), 1145-1149） 2. K. Syoji, T. Kuriyagawa, et al., Development of Ultra-High Speed Surface Grinding

Machine-Studies on Ultra-High Speed Grinding (2nd Report), J of JSPE (Japan Society of Precision Engineering), 63, 4 (1997), 560-564.

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J43 A Study of Ductile/Brittle Mode Grinding of PZT Ceramics Contact Information: Professor Takeshi Tanaka Ritsumeikan University 1-1-1 Nojihigashi, Kusatsu Shiga 527-8577 Japan Email: [email protected] Abstract: Ductile-mode grinding was used to form the surface of PZT ceramics. In order to clarify the formation mechanism of the ground surface, the micro-fracture mechanism and the critical depth of cut of PZT ceramics were examined using a low speed and sub-micron scratching test. Furthermore, a vitrified bonded diamond wheel of fine abrasive grains was used in micro-grinding for obtaining fundamental data regarding the influences of grinding conditions on the formation mechanism of the ground surface. The present paper describes the ductile/brittle mode grinding of PZT ceramics. The following conclusions were obtained after the basic mechanism regarding ductile/brittle mode grinding of PZT ceramics was examined in detail.

• The dc value ranged from 0.14 to 0.23 μm in the sub-micron scratching test at low speed and

at room temperature. It was possible to finish the surface by ductile-mode grinding below these dc values of the wheel depth of cut.

• The dc value increased by heating PZT ceramics to more several tens of degrees • centigrade due to their high sensitivity. • When the wheel depth of cut and the size of grains were small, the surface roughness was

small. The high wheel speed and low workpiece feed provide a rather low degree of roughness.

• Brittle fractures were observed on the finished surface after wet grinding, but the ground surface was formed in the ductile mode without the brittle fractures in dry grinding using SD4000N100V.

Key Issues of the Work:. Status: Completed Publications of this work: 1. T. Tanaka, Y. Isono, M. Kojima, T. Tsuda, A Study on Work Toughening of Zirconia

Ceramics by Grinding Process, The Second International Abrasive Machining Technology Conference; Int. State-of-Art in Abr. Tech. (1995) 41.

2. T. Tanaka, Y. Isono, M. Kojima, T. Tsuda, New Product of Zirconia/Alumina Fine Ceramics Compounds and Its Grinding Characteristics, Proc. of The Eighth Int. Conf. on Production Engineering; Rapid Product Development, (1997) 197.

3. T. Tanaka, Y. Isono, Influences of Phase Transformation and Ground Surface Roughness to Strength of Zirconia/ Nickel Compounds, J. of JSPE, 69, 8 (2003) 1087.

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J44 New Development of a Grinding Wheel with Resin Cured by Ultraviolet Light Contact Information: Professor Takeshi Tanaka Ritsumeikan University 1-1-1 Nojihigashi, Kusatsu Shiga 527-8577 Japan Email: [email protected] Abstract: This paper proposes a unique method for developing a grinding wheel and polishing disk by piling and curing ultraviolet-cured resin mixed with an abrasive grain. The grinding characteristics of the resin-piled grinding wheel (RP wheel) were analyzed by a grinding test. The following conclusions were obtained. • It is clear that the cured depth and width of the ultraviolet-cured resin increase with the

duration of exposure, and that only a 5-10 s exposure time of ultraviolet light is necessary to fabricate the small surface area of the grinding wheels.

• Not only hard and strong wheels, but also elastic wheels were obtained by the selection of resins which fulfill the following conditions: ( a) a proper bending strength; and (b) elastic modulus is used as a grinding wheel.

• It is possible to manufacture polishing disks and grinding wheels that tightly hold and uniformly distribute the abrasive grains. The grinding performance of RP wheel is largely a matte of obtaining sufficient strength and elasticity.

Key Issues of the Work: Status: Completed Publications of this work: 1. T. Tanaka, Y. Isono, H. Shindou, Y. Ishizaki, Development of Grinding Wheel by Rapid

Prototyping and its Grinding Characteristics Investigation, J. of JSAT, 42, 8 (1998) 344. 2. T. Tanaka, K. Okushima, Development of Grinding Wheels by Stereolithography and

Investigation of its Characteristics, Key Engineering Materials, 239-239 (2003) 277. 3. K. Okushima, T. Tanaka, Development of resin-bonded grinding wheel by stereolithography,

J. of JSPE, 69, 10 (2003) 1459.

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J45 Quartz Crystals Ground to Contour, Fixed-Abrasive Polishing of Quartz Contact Information: Researcher Hee-Won JEONG Tokyo Institute of Technology 4259 Nagatsuta, Midori-ku, Yokohama-shi, Kanagawa Japan Email: [email protected] http:www.pme.pi.titech.ac.jp Abstract: Not only the required mode but also many spurious modes can exist on rectangular AT-cut plates. Empirically, in order to eliminate the spurious modes and to achieve high stable and reliable quartz crystal resonators, quartz crystal blanks have been finished into lens-like shape (spherically contoured shape). A new method of finishing spherically contoured quartz crystal blanks is introduced. In this method, the inner curve of a pipe which is used as a barrel in so-called a barrel finishing method can be transferred to the blanks accurately by using abrasive paper (fixed abrasive method) without using powder abrasives. It is also prospective that the dustless clean working environment is realized, because the powder abrasives are not necessary for the fixed abrasive method any more. Key Issues of the Work: • Introducing a fixed abrasive method for finishing spherically contoured quartz crystal

resonators • Development an electromagnetically enforced fixed abrasive polishing equipment • Measuring the shape and frequency characteristics of the quartz resonators fabricated by the

method Status: On-going Publications of this work: 1. International Journal of Machine Tools and Manufacture, “High-Efficiency Fixed Abrasive

Polishing Method for Quartz Crystal Blanks”, Vol.44, No.2-3, pp. 167-173, 2004 2. International Journal of Machine Tools and Manufacture, “Frequency Responses of

Spherically Contoured Rectangular AT-cut Quartz Crystal Resonators Fabricated by Fixed Abrasive Method”, Vol. 44, No. 11, pp1143-1149, 2004

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J46 Dicing of Silicon Wafers Contact Information: Professor Ichiro Inasaki Faculty of Science and Technology Keio University 3-14-1 Hiyoshi, Kouhoku-ku Yokohama-Shi Tel: +81 45 566 1450 Fax: +81 45 566 1452 Email: [email protected] http:www.ina.sd.keio.ac.jp Abstract: Dicing is the final process in the semiconductor device manufacturing that separates the silicon wafer with integrated circuits into individual chips [1]. This means that dicing is the process conducted to highly value-added materials being requested to be extremely reliable. To meet the demands to increase the productivity as a whole, feed rate of the silicon wafer should be increased. However, this leads to some serious troubles such as chipping of the wafer on the kerf, excessive blade wear and meandering of the diamond blade. The last trouble sometimes results in the blade breakage. This project deals with the above mentioned troubles in the dicing process aiming at making clear the influence of setup parameters on those troubles and consequently to make the practical suggestion for improving the productivity of the dicing process. Some troubles in dicing of silicon wafer, such as chipping of the wafer, meandering of the blade and its wear were experimentally investigated. Increase of the blade speed is effective to suppress the water chipping and the blade wear. However, the meandering of the blade that appears to be a kind of instability is apt to occur when the blade speed increases. The stability analysis of this particular phenomenon is necessary to further improve the productivity of the dicing process. Key Issues of the Work: Status: Completed Publications of this work: 1. I. Inasaki: Dicing of Silicon Wafers, Proc. of 3rd International Conference on Micro

Materials, Berlin, Germany, 1002-1017 (2000). 2. T. Miwa, I. Inasaki, I. Yukawa: Blade Wear and Wafer Chipping in Dicing Processes, Trans.

of the Japan Society of Mechanical Engineers, Vol.65, No.630, 369-374 (1999). 3. T. Miwa, I. Inasaki: Blade Wear and Wafer Chipping in Dicing Processes, Proceedings of the

International Conference on Precision Engineering, 397-402 (1997).

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J47 Speed-Stroke Grinding Contact Information: Professor Ichiro Inasaki Faculty of Science and Technology Keio University 3-14-1 Hiyoshi, Kouhoku-ku Yokohama-Shi Tel: +81 45 566 1450 Fax: +81 45 566 1452 Email: [email protected] http:www.ina.sd.keio.ac.jp Abstract: In this study, a surface grinding machine with a linear motor driven table system was developed and its performance tests were conducted to evaluate the developed surface grinding machine. In the machine performance tests, vibration due to table movement, positioning error of the table, table elevation and rise of coil temperature were measured to investigate the influence on the grinding performance. In the grinding tests, surface roughness, grinding force, grinding temperature and wheel radial wear at constant material removal rate with different combinations of the workpiece speed and the depth of cut were measured. The maximum table speed and acceleration achieved were 60 m/min and 1.0 G, respectively. The experimental results proved that the developed surface grinding machine was able to achieve high efficiency grinding. It can therefore be recommended that the proposed linear motors be applied for driving the table system in the surface-grinding machine in order to achieve high frequency reciprocation and fully exploit the advantages of the speed-stroke grinding process. Key Issues of the Work: Status: Completed Publications of this work: 1. T.Kobayashi, I.Inasaki, A.Yui, A.Horikoshi: High-Efficiency Surface Grinding with Linear

Motor Driven Table System, Trans. of the Japan Society of Mechanical Engineers, Vol.66, No.643, 312-316 (2000).

2. I.Inasaki: Surface grinding machine with a linear-motor-driven table system, Annals of the CIRP, Vol.48, No.1, 243-246 (2000).

3. I.Inasaki: Surface Grinding Machine with a Linear-Motor-Driven Table System: Development and Performance Test, Annals of the CIRP, Vol.48, No.1, 243-246 (1999).

4. T.Kobayashi, I.Inasaki, H.Aoyama, A.Yui, A.Horikoshi: Development of Surface Grinding Machine with Linear Motor Driven Table System, Proceedings on the International Seminar on Improving Machine Tool Performance, Vol.1, 77-83 (1998).

387

J48 Grinding Process Simulation Based on the Wheel Topography Measurement Contact Information: Professor Ichiro Inasaki Faculty of Science and Technology Keio University 3-14-1 Hiyoshi, Kouhoku-ku Yokohama-Shi Tel: +81 45 566 1450 Fax: +81 45 566 1452 Email: [email protected] http:www.ina.sd.keio.ac.jp Abstract: The establishment of a reliable model for the grinding process is a key issue in predicting process performance. In this study a method, based on the optical profilometry, to represent 3D grinding wheel surface characteristics is proposed. Considering the wheel topography information, a computer simulation of the grinding process was performed to predict the ground surface roughness and the grinding force. A characteristic feature of the simulation method is that the chip removal process of each individual cutting edge is simulated based on the relative motion between the grinding wheel and the workpiece, to make it possible to predict the surface roughness in three-dimensional space and the cutting force acting upon each individual cutting edge. The estimation of this cutting force provides us the possibility, to some extent, to predict the topography change of the wheel surface during the grinding process. Results of simulations performed in investigating the effect of elevated wheel surface speed confirm the advantage of high speed grinding in terms of the surface roughness as well as the grinding force. Key Issues of the Work: Status: Completed Publications of this work: 1. R.Rentsch, I.Inasaki: Investigation of Surface Integrity by Molecular Dynamics Simulation,

Annals of the CIRP, Vol.44, No.1, 295-298 (1995). 2. R.Rentsch, I.Inasaki: Molecular Dynamics Simulation for Abrasive Processes, Annals of the

CIRP, Vol.43, No.1, 327-330 (1994). 3. I.Inasaki: Grinding Process Simulation Based on the Wheel Topography Measurement,

Annals of the CIRP, Vol.45, No.1, 347-350 (1996). 4. M.Sakakura, I.Inasaki: A Study on a Learning Model for Setup of Grinding Parameters,

Trans. of the Japan Society of Mechanical Engineers, Vol.61, No.585, 346-351 (1995). 5. I.Inasaki: Application of Simulation Technologies for Grinding Operations, VDI Berichte,

No.1276, 197-211 (1996).

388

J49 High-Speed Internal Grinding Contact Information: Professor Ichiro Inasaki Faculty of Science and Technology Keio University 3-14-1 Hiyoshi, Kouhoku-ku Yokohama-Shi Tel: +81 45 566 1450 Fax: +81 45 566 1452 Email: [email protected] http:www.ina.sd.keio.ac.jp Abstract: The effect of high-speed grinding was experimentally investigated for the internal grinding process. In order to access the performance of high-speed grinding, grinding force, surface roughness, and geometrical accuracy of the ground workpiece were measured within the range of wheel surface speed 30m/s-90m/s. Key Issues of the Work: Status: Completed Publications of this work: 1. K.Yasui, I.Inasaki, M.Hatakeyama: Effect of Elevated Wheel Surface Speed in the Internal

Grinding Process, Proceedings of the 9th Annual Meeting on ASPE, 378-381 (1994). 2. G.H.Kim, I.Inasaki, S.W.An, J.K.Lee, J.H.Kang, E.S.Lee: A Study on the Effect of Internal

High-Speed Grinding, Proceedings of the 1st International Abrasive Technology Conference, 92-99 (1993).

3. I.Inasaki, S.O.An, T.Yoshida, M.Wakuda, M.Itagaki: A Basic Study on the Internal High-speed Grinding, Journal of the Japan Society of Grinding Engineers, Vol.37, No.6, 38-42 (1993).

389

KOREA

390

K1 Cooling Effects of Compressed Cold Air and Coolant for Cylindrical Grinding Contact Information: Haedo Jeong School of Mechanical Engineering Pusan National University. Changjun-dong San 30 Pusan 609-735, Korea Email: [email protected] Tel: +82-51-510-2463(Office) Tel: +82-11-876-2463(CP) Abstract: In the grinding process, the coolant has great influence on the environment. It contains chlorine, sulfur and phosphorus to improve the grinding efficiency. These additives, however, degenerate the workplace atmosphere and in the end cause the environmental pollution. This study focused on the effects of the cooling methods (coolant, mist and compressed cold air) when the spindle shaft material (SCM21) was cylindrically ground with CBN & WA (white alumina) wheels. The cooling effect of the mist and compressed cold air were introduced and compared with that of the coolant. To get the lower air temperature, the constant-temperature water bath and vortex tube was used. The mist and compressed cold air were also very effective to minimize the thermal defects of the surface layer. It could also play a role in solving the environmental problems. Moreover, using of the mist could minimize the coolant amount and the grindability of workpiece was increased. The conclusions are drawn as follows: • The cooling effect of the coolant is better than that of the mist and compressed cold air

coolant. • Coolant has low grinding resistance since its lubrication performance is good but the

grinding resistance is most large in the use of compressed cold air. • The roundness with the mist was better than that with the coolant and compressed cold air. • As the temperature of the mist decreases, the surface roughness and roundness are better. Key Issues of the Work: o Improvement of the grinding efficiency o Effects of the cooling methods (coolant, mist, and compressed cold air) Status: Completed Publications of this work: 1. H. Z. Choi, S. W. Lee, J. S. Ahn, "A study on the surface integrity for the cylindrical

grinding with compressed cold air", ISAAT, pp. 187-192, 1998 2. H. Z. Choi, S. W. Lee, H. D. Jeong, "A comparison of the cooling effects of the compressed

cold air and coolant for cylindrical grinding with CBN wheel". Proceeding of AFDM, pp. 319-322, 1999

391

3. H. Z. Choi, S. W. Lee, J. S. Ann, "A comparision of the cooling effects of the compressed cold air and coolant for the cylindrical grinding". International EUSPEN conference, pp. 416-419, 1999

4. H. Z. Choi, S. W. Lee, D. J. Kim, and H. D. Jeong, Grinding Of Spindle Shaft Material With Mist Type Coolant, International Symposium on Advances In Abrasive Technology (ISAAT), 2000

392

K2 Fixed-Abrasive Pad for Chemical Mechanical Polishing of Micro Patterns Contact Information: Haedo Jeong School of Mechanical Engineering Pusan National University. Changjun-dong San 30 Pusan 609-735, Korea Email: [email protected] Phone +82-51-510-2463(Office) +82-11-876-2463(CP) Abstract: The fixed abrasive pad (FAP) is an alternative tool to achieve nanometer order surface. FAP has a couple of advantages including clean environment, lower CoC, easy controllability and higher form accuracy. However FAP needs conditioning process. This researcher developed self-conditioning FAP using hydrophilic polymers with swelling characteristics in water. Experimental results showed self conditioning characteristics and nano surface roughness in metal mold and soda lime glass for optic applications, and higher planarity in STI and Tungsten patterns than that of conventional chemical mechanical polishing. Key Issues of the Work: • Self conditioning process using swelling characteristics of polymer • High pattern selectivity • Low defect • Micro replication technique Status: Completed 2003 Publications of this work: 1.

2.

3.

4.

5.

6.

7.

8.

H.Y. Kim, H.J. Kim, H.D.Jeong : Development of a Semi-rigid Abrasive Pad for Chemical Mechanical Polishing, ABTEC Proceedings, Korea, 1999 H.Y. Kim, H.J. Kim, H.D.Jeong: Development of an Abrasive Embeded Pad For Dishing Reduction and Uniformity Enhancement, Journal of Korean physical society, Vol.37, No.6, 945~951 (2000). H.D. Jeong, H.Y. Kim, J.Y. Park, C.W. Nam, S.I. Lee : Development of abrasive Capsulation Pad Using Water Swellable Polymer, CMP-MIC, USA, 2001 H.D. Jeong, H.Y. Kim, J.H. Park : A study of the abrasive pad for chemical mechanical polishing, ISAAT, Korea, 2001 H.Y. Kim, J.H. Park : Evaluation on a Pattern Selectivity in Fixed Abrasive Pad Using Hydrophilic Polymer, CMP-MIC, USA, 2002 H.Y. Kim, B.Y Park, S.I. Lee, H.D. Jeong, David A. Dornfeld: Application of Fixed Abrasive Pad using hydrophilic polymer in STI CMP, ASPE, USA, 2002 H.D. Jeong, H.Y. Kim, J.Y. Choi, B.Y. Park, H.Y. Kim, H.D. Seo, J.H. Park, Naoto Kubo, Hitoshi Omori :The Challenge and opportunity of fixed abrasive pad in optics and semiconductors, International Workshop on Extreme Optics and Sensor, Japan ,2003 J.Y. Choi, H.Y. Kim, J.H. Park, H.D. Seo, H.D. Jeong: A study on Nano-polishing of

393

Injection Molds using a fixed abrasive pad, Key Engineering materials, Vol 238-239, 247-252 (2003).

9.

10.

11.

12.

H.Y. Kim, H.J. Kim, H.D. Seo, S.J Lee, H. D. Jeong : Self-conditioning of encapsulated abrasive pad in chemical mechanical polishing, Journal of Materials Processing Technology, Vol 142, 614-618 (2003). J.Y. Choi, H.Y. Kim, J.H. Park, S.I. Chung, H.D. Jeong, M. Kinoshita : A study on the manufacture of the next generation CMP pad with a uniform shape using the Micro-Molding method, Key Engineering materials, Vol 257-258, 413-416, (2004). J.Y. Choi, H.D. Jeong : A study on polishing of molds using hydrophilic fixed abrasive pad, Journal of Machine Tools and Manufacture, Vol. 44, 1163-1169,(2004) H.Y. Kim, B.Y. Park, S.J. Lee, H.D. Jeong, David A. Dornfeld : Self-Conditioning Fixed Abrasive Pad in CMP, Journal of The Electrochemical Society, Vol.151, No.12, (2004)

394

K3 Grinding of Stainless Steel with Ultrasonic In-process Dressing Method Contact Information: Haedo Jeong School of Mechanical Engineering Pusan National University. Changjun-dong San 30 Pusan 609-735, Korea Email: [email protected] Tel: +82-51-510-2463(Office) Tel: +82-11-876-2463(CP) Abstract: The investigation of the effect of ultrasonic in-process dressing (ULID) on the grinding characteristics was implemented. The ULID method is that ultrasonic vibration in any position of wheel is used to remove impurities on the wheel surface. The ratio of surface roughness change in grinding by the ULID method was less than that of conventional grinding without ultrasonic vibration, by preventing loading phenomena. Key Issues of the Work: • ultrasonic in-process dressing(ULID), Loading, CBN wheel, Surface roughness Status: Completed Publications of this work: 1. H. D. Jeong: Mirror Surface Grinding Using Ultrafine Grit Wheel, 2nd Int l ABTEC Conf.,

pp.257-262, 1995. 2. H. D. Jeong , S. W. Lee, Y. C. Lee, H. Z. Choi: The Improvement of Form Accuracy by High

Pressure Air Jet in Slot Grinding, ASPE 1998 Proceeding, pp145-148, 1998. 3. H. D. Jeong, S. J. Lee, Y. S. Lee, H. Z. Choi: Study on Chemical Defect Analysis of Ground

Surface in Silicon Wafer Grinding, Proceedings Of 4th Korea-Japan Joint Technical Conference on Surface Finishing & Burr Technology, pp130-138, 1999.

4. H. D. Jeong , S. W. Lee, Y. C. Lee, H. Z. Choi: Grinding of Stainless Steel with Ultrasonic In-process Dressing Method, AFDM 1999 Proceedings, pp315-319, 1999.

5. H. D. Jeong , S. W. Lee, Y. C. Lee, H. Z. Choi: The Grindability of Stainless Steel using ULID(Ultrasonic In-process Dressing) Method, ABTEC 1999 Proceedings, pp19-24, 1999.

6. H. D. Jeong, D. J. Chung: Development of heat source model to creep feed Grinding, ISAAT2000, pp495-502, 2000.

7. H. D. Jeong, H. Y. Kim, S. J. Lee, H. Z. Choi: Development of ultrafine grit wheel using continuous build-up process for photocurable polymer, ISAAT2000, pp464-471

8. H. D. Jeong: Intergrated Planarization technique with Consistency in Abrasive Machining for Advanced Semiconductor Chip Fabrication, CIRP, Vol. 45/1, pp 311-314, 1996.

9. S. W. Lee, Y. C. Lee, H. D. Jeong, H. Z. Choi: The effect of high pressure air jet on form accuracy in slot grinding, Journal of Materials Processing Technology, Vol. 128, ISS 1-3, pp 67-72, 2002.

395

K4 Intelligently Automated Fixed-Abrasive Polishing for High Quality Surface Formation of Sculptured Die and Mold Contact Information: Haedo Jeong School of Mechanical Engineering Pusan National University. Changjun-dong San 30 Pusan 609-735, Korea Email: [email protected] Phone +82-51-510-2463(Office) +82-11-876-2463(CP) Abstract: An intelligence polishing system that improves the surface quality of sculptured die surfaces on a 5-axies polishing machine including a pneumatic polishing head is proposed. In general, a mechanically automated polishing system has the critical drawback of not being able to adjust polishing conditions as adequately as an experienced operator can. One of the main reasons is that the system does not have sensors equal to human fingers that can adapt to the changing conditions of the polished surface. Acoustic emission (AE) sensors are adopted to detect even a tiny change of the polishing system status. Based on the on-site status information, polishing conditions such as pressure, feedrate, and tool mesh are adjusted in process to achieve better surface quality as fast as possible using an AE-based intelligent monitoring scheme. Key Issues of the Work: • Acoustic emission (AE) sensors • Polishing system Status: Publications of this work: 1.

2.

3.

4.

H. D. Jeong, Y. F. Shen, H. Y. Kim, J. H. Ahn, G. K. Cho: Development of a sensor information integrated expert system for optimizing die polishing, Proceedings of FAIM 2000, Vol 1 pp307-316, 2000. H. D. Jeong, J. H. Ahn, D. J. Lim, C. H. Whang: Development of elastic finishing tool for high form accuracy of die and molds, ISAAT2000, pp430-437, 2000 J. H. Ahn, Y. F. Shen, H. Y. Kim, H. D. Jeong, G. K. Cho: Development of a sensor information integrated expert system for optimizing die polishing, ROBOTICS AND COMPUTER-INTEGRATED MANUFACTURING, Vol. 17, No 4, pp269-276, 2001. J. H. Ahn, M. C. Lee, H. D. Jeong, G. K. Cho: Intelligently automated polishing for high quality surface formation of sculptured die, Journal of Materials Processing Technology, Vol.130, pp339-344. 2002.

396

K5 Effects of Minimizing Hydrodynamic Pressure in Ultra-precision Mirror Grinding Contact Information: Sun-Kyu Lee Dept. Mechatronics Gwangju Institute of Science and Technology Korea Tel: +82-62-970-2388 Fax: +82-62-970-2384 Email: [email protected] Abstract: This summary describes an investigation about the fluid delivery method that minimizes the generation of hydrodynamic pressure and that improves grinding accuracy. Traditionally, grinding fluid is delivered for the purpose of cooling, chip flushing and lubrication. Hence, numbers of conventional investigations are focused on the delivery method to maximize fluid flux into the contact arc between grinding wheel and workpiece. It is already known that hydrodynamic pressure generates due to this fluid flux, and that it affects overall grinding resistance and machining accuracy. Especially in the ultra-precision mirror grinding process that requires extremely small amount of cut per each pass, its influence on the machining accuracy becomes more significant. Therefore, in this paper, a new delivery method of grinding fluid is proposed on the point of minimizing hydrodynamic pressure effect with resin-bonded fine diamond wheel. Experimental data indicates that the proposed method is effective not only to minimize the hydrodynamic pressure but also to improve machining accuracy. It is found that hydrodynamic pressure is created in accordance with the boundary film thickness. By altering the location of fluid delivery nozzle, the film thickness can be significantly reduced. It is also found that grinding fluid delivered from the diverging zone against wheel rotational direction in the process of down cutting decreases pressure generation and provides large effect on the improvement of machining accuracy for the small depth of cut. For the realization of the proposed method in the practical application, behavior of overall grinding resistance and wheel conditions over the long machining period should be further investigated. Status: Ongoing Publications of this Work: 1. Katsushi Furutani, Noriyuki Ohguro, Nguyen Trong Hieu and Takashi Nakamura, In-process

measurement of topography change of grinding wheel by using hydrodynamic pressure, Int.J.Machine Tools and Manufacture 42(13) (2002) 1447-1453.

2. Y.Wu, M.Kato and T.Kuriyagawa, High Velocity Fluid Polishing of Optical Components, res. report of Prec. Machining Laboratory of Tohoku University (Shutsuran,2003) 29-34.

397


POLAND

398

P1 An intelligent system for supervision and control of traverse grinding operation Contact Information: Professor Bogdan Kruszyński Institute of Machine Tools & Production Engineering Technical University of Łódź ul Stefanowskiego 1/15 90-924 Łódź Poland Tel: +48 42 631 22 99 Fax: +48 42 636 57 26 Email: [email protected] Abstract: An intelligent control system for a cylindrical traverse grinding process whose task is to produce parts satisfying the geometrical and surface finish requirements with maximum possible productivity. Key Issues of the Work: • Development of the new control and monitoring system Status: ongoing Publications of this work: 1. B. W. Kruszyński, P. Lajmert, An intelligent control system for optimising traverse

grinding operation, 3rd Int. Conf. on Advances in Production Engineering, Warsaw, 2004, pp. 211-220.

399

P2 Influence of Grinding Wheel on Fatigue Strength of Spur Gears Contact Information: Professor Bogdan Kruszyński Institute of Machine Tools & Production Engineering Technical University of Łódź ul Stefanowskiego 1/15 90-924 Łódź Poland Tel: +48 42 631 22 99 Fax: +48 42 636 57 26 Email: [email protected] Abstract: Investigations on influence o grinding wheel properties (conventional and CBN) on bending fatigue strength of gear teeth are carried out. Experiments are carried out for conventionally and vaccum carburized gears in wide range of grinding parameters. Key Issues of the Work: • Synergistic effect of vacuum carburizing and CBN grinding on fatigue strength of gears Status: ongoing Publications of this work: 1. Kruszyński B., Zgórniak P. An Experimental Stand For Fatigue Testing Of Spur Gears, 4th

Int. Conf on Development of Metal Cutting, DMC 2002, Koszyce, Slovakia. 2. Z. Gawronski, B. Kruszynski & P. Kula “Synergistic Effects of Thermo-Chemical Treatment

and Super Abrasive Grinding in Gears' Manufacturing” to be published in Journal of Materials Processing Technology.

400

P3 Investigation of Magnetic Composite Grinding Process with Application of MQL Contact Information: Professor Bogdan Kruszyński Institute of Machine Tools & Production Engineering Technical University of Łódź ul Stefanowskiego 1/15 90-924 Łódź Poland Tel: +48 42 631 22 99 Fax: +48 42 636 57 26 Email: [email protected] Abstract: Investigation on grinding process of sandwich-like magnetic ceramics is carried out for different grinding wheels (conventional aluminum oxide, CBN,TGP, etc.) as well as for different grinding fluid supply (dry, MQL and flood). Thermal model was developed to calculate temperature and temperature gradient distributions. Experiments to measure grinding forces as input to temperature calculations as well as grinding temperatures were carried out. Key Issues of the Work: • Development of the model • finding optimal grinding conditions to satisfy quality requirements such as magnetic

properties, surface roughness, no microcracks and grinding efficiency. Status: will be completed in 2005 Publications of this work: 1. B. Kruszyński, J. Pazgier Temperatures in Grinding of Magnetic Composites - Theoretical

and Experimental Approach. Annals of the CIRP, 52/1/2003, p.263-266

401

P4 The Fundamentals of Production and Applications of Ceramic Abrasive Tools made from Aluminum Oxide (Alumina) Obtained by Sol-Gel Technique and Sub-Microcrystalline Boron Nitride with Glass-Crystalline Binders.

Contact Information: Dr Eng. Daniela Herman Inst.of Mats. Sc. & Tech. Technical University ul.Racławicka 15/17 75-620 Koszalin Poland tel.: +48 94 3478 346 fax :+48 94 3478 499 e-mail: [email protected] Abstract: Experimental investigations have revealed that the substitution of glass binders, widely applied so far to abrasive tool engineering, for glass-crystalline binders makes it possible to obtain tools marked by high grinding performance. The work of adhesion Wa for grain-bond fixing was higher when glass-crystalline binders were applied. Due to the crystallization of binders the mechanisms of micro-chipping in the process of grinding could be closer which allowed the grinding power to be reduced. It is possible to increase the fracture toughness index comparing with amorphous binders through the proper selection of binder chemical composition. The tools made of sub-microcrystalline aluminum oxide and boron nitride on the basis of such the binders were experimentally investigated in the course of inside diameter grinding of rings made of bearing steel. Key issues of the work: Studying the phenomena on the abrasive grain – binder interface Thermal process technology for tools Studying the effects of binder crystallization on the grinding-wheel wear and the machined surface roughness Status: implementation in progress. Publications of this work: 1. Herman D: Glass and glass-ceramic binders for abrasive grains of fused and sintered alumina

type SG into abrasive tools. Key Engineering Materials Vols. 132-136 (1997),2180-2183. 2. Herman D.,Plichta J.,Karpiński T.:Effect of glass-crystalline and amorphous binder

applications to abrasive tools made of microcrystalline alumina grains type SG. Wear 209,1997, 213-218.

3. Herman D.: Glass and glass-ceramic binder obtained from waste material for binding alundum abrasive grains into abrasive tools.Ceramic International, vol.24,1998,515-520.

4. Herman D.: Selected issues of production technology for ceramic grinding wheels made from fused aluminum oxide and obtained from gel. Polish Ceramic Bulletin PAN, vol.60,151-157, Kraków,2000,

402


5. Herman D., Markul J.: Influence of microstructures of binder and abrasive grain on selected operational properties of ceramic grinding wheels made of alumina. International Journal of Machine Tools and Manufacture,44 (2004)511-522.

6. Herman D., Transition zone structure a-Al2O3 –glass crystalline material from the CMAS system, Ceramika/Ceramics, Polish Ceramic Bulletin PAN 2004 (at the printer’s).

403

RUSSIA

404

R1 New, Highly-Porous Bonded Abrasives for Progressive State-of-The-Art in Ecologically-Compatible Technology

Contact Information: Prof., Dr. Sc. techn. Victor K. Starkov Research Center "NOVEL TECHNOLOGIES & TOOLING" Moscow State Technological University “STANKIN”, Vadkovskii pereulok 3a, 127055 Moscow, Russian Federation Tel +7 095 973 3981, Tel/Fax +7 095 972 94 51 Email: [email protected] or [email protected] Abstract: The development of new generation of highly-porous wheels with structure numbers 10-26 and working speeds till 120-150 m/s on the basis of non burning out cellulating agents such as an microspheres. This work was done within the framework of International Program EUREKA of European Union’s countries (E!2581 EUROENVIRON KORUND). Key Issues of the Work:

A ecologically-compatible technology of production of highly-porous abrasive tools. • •

•

1.

2.

3.

A high productivity burnless grinding by methods of pendular grinding and deep grinding of iron- bearing, nikel- bearing, titanium-bearing, magnetic materials and etc. On operation of deep grinding of a attachments of turbine blades a work speed is increased till 70 m/s.

Status: Completed 2004 Publications of this work:

Starkov V.K.: New generation of high-porous abrasive tool, ISN 0042-4633 Vestnik Maschinostroenia, No. 4, 56-62 (2002) Starkov V.K., Ryabtsev S.A., Frumar J., Fryč P., Vysokorychlostní broušení vysokopórovitỳmi brusnỳmi kotouči, 2nd Mezinárodni kongres «Přesné obrábění», Praga, 257 – 262 (2003). Page “E!2581 EUROENVIRON KORUND” on web-site:

www.eureka.be/inaction/portfolio.do

405

R2 Technologies of Ecologically Friendly High-Speed Grinding without Application of Coolants

Contact Information: Prof., Dr. Sc. techn. Victor K. Starkov Research Center "NOVEL TECHNOLOGIES & TOOLING" Moscow State Technological University “STANKIN”, Vadkovskii pereulok 3a, 127055 Moscow Russia Tel +7 095 973 3981, Tel/Fax +7 095 972 94 51 Email: [email protected] or [email protected] Abstract: Was researched a relationships of tools wear and thermodynamics of dry grinding of hardened steels on work speeds from 35 till 96 m/s by abrasive wheels with various characteristics, including highly-porous wheels with structure numbers 15-20. This work was done within the framework of International Program EUREKA of European Union’s countries (E!1690 EUROENVIRON ABRASIVE 2000). Key Issues of the Work: The intensity of heat buildup is reduced till 4 times on grinding by new highly-porous wheels and simultaneously a metal-removal rate is increased about 41 times. Status: Completed 2001 Publications of this work: 1.

2.

3.

Starkov V.K.: Thermodynamics of high-speed grinding without cutting fluid application, ISN 0042-4633 Vestnik Maschinostroenia, No. 9, 50-55 (2002) Harzbecker K., Starkov V.K., Ovchinikov D.S.: High-speed dry grinding of hardened steels, ISN 0042-4633 Vestnik Maschinostroenia, No. 9, 43-50 (2002) Page “E!1690 EUROENVIRON ABRASIVE 2000” on web-site

http://www.eureka.be/inaction/portfolio.do

406

R3 Deep Profile Grinding of Gear-Wheels Contact Information: Prof., Dr. Sc. techn. Victor K. Starkov Research Center "NOVEL TECHNOLOGIES & TOOLING" Moscow State Technological University “STANKIN”, Vadkovskii pereulok 3a, 127055 Moscow Russia Tel +7 095 973 3981, Tel/Fax +7 095 972 94 51 Email: [email protected] or [email protected] Abstract: Theory and experimental research of shaping of gear wheels and cogged joints with module 1-8 mm by method of deep profile grinding by special developed highly-porous wheels. A theory, researches and recommendations on burnless grinding of gear wheels by methods of form-grinding, template-grinding and generating, including a machining after carbonization, nitriding, carbonitriding. This work was done within the framework of International Program EUREKA of European Union’s countries (E!2339 EUROENVIRON GRINDING). Key Issues of the Work: A flexible and economic efficiently technology of shaping of gear wheels in quantities 1-50 pieces by grinding on one machine with quality 2-3 class, which dispose of machining by cutting tools. Status: Completed 2003 Publications of this work: 1.

2.

3.

Starkov V.K.: Theoretical prerequisites for deep profile gear grinding, ISN 0042-4633 Vestnik Maschinostroenia, No. 3, 39-55 (2002) Starkov V.K, Ryabtsev S.A., Soloduhin N.N.: The representative technology of gear-wheels manufacturing by the profile feed work method, 3nd International Conference Research and Development in Mechanical Industry, RaDMI 2003. Herceg Novi (Montenegro Adriatic), 534 – 537 (2003) Page “E!2339 EUROENVIRON GRINDING” on web-site


407

R4 Development of Highly Effective and Ecologically Safe Technologies of Detail’s Shaping of Mechanical Engineering on the Basis of Creation new Highly-Porous Dressable Tool from Cubic Boron Nitride.

Contact Information: Prof., Dr. Sc. techn. Victor K. Starkov Research Center "NOVEL TECHNOLOGIES & TOOLING" Moscow State Technological University “STANKIN”, Vadkovskii pereulok 3a, 127055 Moscow Russia Tel +7 095 973 3981, Tel/Fax +7 095 972 94 51 Email: [email protected] or [email protected] Abstract: A development of compounds and constructions of dressable cubic boron nitride wheels, which cutting properties analogous to a traditional wheels. A researches of various grinding process with this wheels . This work was done within the framework of International Program EUREKA of European Union’s countries (E!3274 EUROENVIRON ELBOR). Key Issues of the Work: • Was created a dressable grinding wheels from CBN, which has a cost of a unit of specific

capacity is smaller in 3-7 times than for traditional wheels from CBN. • Was received a good results on profile grinding of gear wheels and shaped cutting tool and

on pendular grinding of details from titanium alloys, nickel alloys and hardened steels. Status: In progress Publications of this work: 1.

2.

Starkov V.K., Ryabtsev S.A., Polkanov Ye.G.: Development and application of the high-porous cubic boron nitride abrasive wheels, ISN 1562-322X Tehnologiya maschinostroenia, No. 4, 26-33 (2004) Page “E!3274 EUROENVIRON ELBOR” on web-site


408

SINGAPORE

409

S1 Modeling and Topographic Study of the Precision Grinding Process Contact Information: Assistant Professor David Butler School of MPE Nanyang Technological University Singapore S639798 Email: [email protected]://www.ntu.edu.sg/home/mdlbutler/Research/researchindex.htm Abstract: This work is aimed at providing a better understanding of the grinding process through the development of better simulation models combined with the topographic analysis of both the wheel and workpiece. Utilising a novel set of three-dimensional surface parameters and combining with an optimized measurement strategy, a new insight into the wheel-workpiece interaction is possible. Key Issues of the Work: • The development of FEM and simulation models capable of predicting the final workpiece

topography • The development of a measurement technique capable of quantifying and characterizing the

wheel topography, cutting grain density and wheel sharpness. Status: On-going Publications of this work: 1. Nguyen T.A, D.L. Butler, "Simulation of Precision Grinding Process for Predicting Surface

Roughness", MATADOR, Manchester, July 2004 2. T.A. Nguyen, Butler D.L., "A Methodology for Simulation of Grinding Wheel Surfaces for

Precision Surface Grinding" , ICoPE 2003/04, Singapore, March 2004 3. Butler D.L., S.C Chan, K. Ramesh, H. Huang, "CBN Grinding of Inconel- A Topographic

Approach to Process Characterisation", ICoPE 2003/04, Singapore, March 2004 4. D. L. Butler, L. A. Blunt, B. K. See, J. A. Webster and K. J. Stout, "The characterisation of

grinding wheels using 3D surface measurement techniques", Journal of Materials Processing Technology, Volume 127, Issue 2, 30 September 2002, Pages 234-237

5. D.L. Butler, L.A. Blunt, B.K. See, J.A. Webster, and K.J. Stout, "The Characterisation of Grinding Wheels using three-dimensional surface measurement techniques", ICoPE 2000, Singapore March 2000

6. Butler D.L., J. Webster, Liam Blunt, and K.J. Stout, "The Three-Dimensional Surface Topographic Characterisation Of Conventional And Superabrasive Grinding Wheels", ASPE Annual Conference, California, October 1999

410


S2 Towards Grinding Efficiency Improvement using a New Oil-Air Mist Lubricated Spindle Contact Information: Assoc Professor Swee-Hock YEO School of Mechanical and Production Eng Nanyang Technological University 50 Nanyang Avenue Singapore 639798 Tel: +65 6790 5539 Email: [email protected] Abstract: Most research work on ultra high speed grinding processes are related to process applications that use a hydrodynamic spindle with silicon nitride balls as the rolling elements. This study investigates the ultra high speed grinding process behaviour using a newly designed oil-air mist lubricated spindle. The main emphasis is vested with the issues: (a) development of a new oil-air mist lubricated spindle and (b) ultra high speed grinding spindle process characterization for hard-tough materials and thin-fragile components. Key Issues of the Work: • Tribological behaviour between rolling elements and bearing races • Thermal management study by convention, latent heat due to evaporation and sensible heat

due to mist collision • Process characterization using a physical model which links the process parameters with

boundary conditions; includes grinding forces, power flux, grinding-ratio, grinding wheel topography, surface and sub surface damage, surface finish and stress analyses

• Coolant shoe development to increase coolant penetration to the grinding zone Status: Completed 2002 Publications of this work: 1.

2.

K. Ramesh, S.H. Yeo, S. Gowri, L Zhou: Experimental Evaluation of Super High Speed Grinding of Advanced Ceramics, Int J of Advanced Manufacturing Technology, 17(2), 2001, pp.87-93 S.H. Yeo, K. Ramesh, Z.W. Zhong: Ultra High Speed Grinding Spindle Characteristics Upon Using Oil-Air Mist Lubrication, Int J of Machine Tools and Manufacture, Vol.42, 2002, pp.815-823.

411

SLOVENIA

412

SL1 Development of a High-speed Cylindrical Grinding Machine Contact Information: Peter Krajnik, Postgraduate student Faculty of Mechanical Engineering University of Ljubljana Askerceva 6, SI-1000 Ljubljana Slovenia, EU Tel: +386 41 734160 Fax: +386 1 2518 567 Email: [email protected] http: www.fs.uni-lj.si Summary: This paper reviews the modern aspects of grinding with regards to enhanced productivity and manufacturing quality demands. The basic mechanism of grinding and the applications for the state-of-the art technology of high-speed grinding (HSG) with high-performance grinding wheels are presented. In addition to the improvements in the technology associated with HSG, the grinding machine-tool, the coolant system and the process monitoring also need to adapt to high-speed machining. In addition, the ground surface integrity and the economic efficiency of HSG are also briefly discussed. Because of the unequivocal competitive position of the discussed procedure, Slovenian industry will necessarily have to consider future investments in modern high-performance grinding systems. In this way, HSG represents a new challenge for Slovenian manufacturing. (This work was the first review of HSG in Slovenian language designed for presentation of the HSG technology to Slovenian manufacturing environment) Publications of this work: 1. P. Krajnik, J. Kopac: A review of High-Speed Grinding and High-Performance Abrasive

Tools, Journal of Mechanical Engineering, Vol. 50/4, 2004.

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SL2 Matrix Experiments for Efficient Grinding Cycle Design Contact Information: Peter Krajnik, Postgraduate student Faculty of Mechanical Engineering University of Ljubljana Askerceva 6, SI-1000 Ljubljana Slovenia, EU Tel: +386 41 734160 Fax: +386 1 2518 567 Email: [email protected] http: www.fs.uni-lj.si Summary: The research deals with the design of grinding parameters based on the matrix experiments. The fundamental aspect of the presented method, appropriate for the off-line quality control, refers to combining the experimental design with the quality loss. Experimental design matrix is founded on standard orthogonal array. The objective of this research refers to determination of optimal system set-up for various quality defining characteristics. The aforementioned problems are solved by the concept of signal-to-noise (S/N) ratio. Another research refers to a process characterisation in term of fast mapping of grinding parameters with the minimum amount of test data. The research is based on two-level matrix experiment. Within the research, factor effects are determined and compared to referential values obtained by industrially validated empirical model. The purpose of fast process characterisation refers to assessment of process set-up parameters that are important for making improvements towards increased productivity. Efficiency of presented experimental approach has been investigated on the surface grinding process. Submitted publications of this work: 1.

2.

3.

J. Kopac, P. Krajnik, J.M. d’Aniceto: Grinding Analysis Based on the Matrix Experiment, 13th International Scientific Conference on Achievements of Mechanical and Materials Engineering AMME'2005, Worldwide Congress of Materials and Manufacturing Engineering and Technology COMMENT'2005, 16-19 May 2005, Gliwice-Wisla, Poland. P. Krajnik, J. Kopac. Efficiency of fast process characterization in grinding, Manufacturing and management in 21st century : conference proceedings. Skopje: Production and Industrial Engineering Association, 2004, chapter one, p.p. 256-261. P. Krajnik, J. Kopac: Adequacy of matrix experiment in grinding, Journal of Materials Processing Tech., Vol. 157-158C pp 566-572, 2004.

414


SL3 Regression Modelling and Optimization of Centerless Grinding Contact Information: Peter Krajnik, Postgraduate student Faculty of Mechanical Engineering University of Ljubljana Askerceva 6, SI-1000 Ljubljana Slovenia, EU Tel: +386 41 734160 Fax: +386 1 2518 567 Email: [email protected] http: www.fs.uni-lj.si Summary: The experimental work deals with a systematic methodology for empirical modelling and optimization of the plunge centreless grinding process. The assessment of microgeometric quality defining quantity is supported by post-process surface roughness measurements. Modelling is based on response surface methodology (RSM), which integrates a central composite design (CCD) of experiments and computer aided linear regression analysis (LRA) for fitting a model to experimental data. Data analysis relates to design evaluation, which is supported by various advanced estimates of the regression matrix, and model analysis, which includes a full analysis of variance (ANOVA), prediction equations and response surface plots.. The computer-aided single-objective optimization, solved by nonlinear programming and genetic algorithm, is applied. The results of two different optimization approaches for determination of optimal operating conditions are compared. Key Issues of the Work: • The major goal of experimental study focuses on determination of optimum centreless

grinding system set-up and operating conditions for minimization of surface roughness. • The RSM is very convenient for simple adaptation to multi-response modelling, which is

necessary for further process improvement. In this way the macro-geometrical component quantities, production rate and grinding costs have to be included in the process modelling and our future research activities. This is especially important in centreless grinding, whose fundamental component quality loss relates to roundness error, caused by regenerative chattering, geometrical rounding effects and other disturbances of complex character.

Status: Experiments completed in 2004, papers have been recently submitted for publishing. Submitted publications of this work: 1.

2.

P. Krajnik, J. Kopac, A. Sluga: Design of Grinding Factors Based on Response Surface Methodology, Advances in Materials and Processing Technologies AMTP, Worldwide Congress of Materials and Manufacturing Engineering and Technology COMMENT'2005, 16-19 May 2005, Gliwice-Wisla, Poland P. Krajnik, J. Kopac, A. Sluga: Regression Modelling of Surface Texture in Grinding, 8th CIRP International Workshop on Modelling of Machining Operations, 10-11 May 2005, Chemnitz, Germany

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4.

P. Krajnik, J. Kopac: Empirical Surface Texture Modelling in Precision Grinding, 7th International Conference on Advanced Manufacturing Systems and Technology, AMST 2005, Udine, Italy J. Kopac, P. Krajnik, A. Sluga: Precision Grinding and Quality Control, V: J. Madl (eds.). ICPM 2003, proceedings: 2nd International Congress of Precision Machining, 3-6 September 2003, Prague. Department of Manufacturing Technology, Faculty of Mechanical Engineering, page 36-41, 2003.

416

SPAIN

417

SP1 Analysis Of The Electro Discharge Dressing (Edd) Process Of Large-Grit Size CBN Grinding Wheel

Contact Information: Dr. J.A. Sanchez Department of Mechanical Engineering University of the Basque Country Bilbao, Spain Tel: +34946014068 Fax: +34946014215. E-mail: [email protected] Abstract: Electro Discharge Dressing (EDD) is a non-conventional technology used for trueing and dressing of conductive bond superabrasive grinding wheels. Much research work has been done on the optimum application of this technology, especially in the case of small grit size wheels. However when it comes to the dressing of large-grit size superabrasive wheels little information is available. In this work a scientific description of the mechanisms involved in bonding material removal in the EDD of large-grit size wheels is presented. Indicators are defined in order to quantify the stability and efficiency of the process, and the influence of the main variables (wheel speed, electrode size and electrical settings) is analysed. Practical application shows that very important improvements in the grinding performance of the wheels can be obtained by maximising grit protrusion while avoiding grain loss using this technique. Key Issues of the Work: Status: Ongoing Publications of this work: Submitted

418

SP2 Broach Grinding Contact Information: Rafael Lizarralde Mechanical Department Ideko, Centro Tecnológico Polígono de Arriaga, 2 – 20870 – Elgoibar, Spain Tel:+34 943748000 Fax: +34 943743804 Email: [email protected] http:www.ideko.es Abstract: Development of a new machine concept and software for the accurate grinding of helical broaches with full form. New mathematical algorithms have been developed in order to perform an optimal wheel dressing, by means of the calculation of the wheel profile required depending on the broach main parameters and the diameter of the tool.

Key Issues of the Work: • Dressing corrections for helical grinding • Dressing corrections for full form in helical broaches applications. • New machine prototype patented by Danobat. • Selection of better grind conditions for one optimal constructions of broaches. Status: Completed in 2003 Publications of this work:

419

SP3 Modeling of Centerless Grinding Stability Contact Information: Rafael Lizarralde Mechanical Department Ideko, Centro Tecnológico Polígono de Arriaga, 2 – 20870 – Elgoibar Spain Tel:+34 943748000 Fax: +34 943743804 Email: [email protected] http:www.ideko.es Abstract: Elimination of geometric lobing in centerless grinding has been widely and deeply investigated. Several models with quite good results have been developed, but no practical tool has been implemented in machines to ease the setting up of the machine in stable conditions. In this work a software for the setting up and optimization of centerless grinding process to avoid geometric instability. For plunge grinding, the practical result is the generation of stability maps showing the stable and non-stable geometric configurations and the number of lobes generated in non-stable conditions. Time domain models predict quantitatively the evolution of the profile error with the part rotations for each geometric configuration. Finally, for through feed grinding the models are able to predict the stable or unstable conditions in the whole evolution of the workpiece between wheels. Key Issues of the Work: • Stability frequency domain models for geometric lobing, including the flexibility of the

machine and elements. • Time domain models including nonlinearities such as the contact between workpiece, wheels

and blade. • Obtention of stability maps useful for machine operators, showing the stability areas for

different configurations (blade angle and height above centers). • Efficient algorithms to obtain the stability maps in shot time. Status: Completed in 2004 Publications of this work: 1. Gallego, I., Barrenetxea, D., Rodriguez, A., Marquinez, J. I., Unanue, A., Zarate, E. (2003).

"Geometric Lobing Suppression in Centreless Grinding by New Simulation Techniques". The 36 CIRP International Seminar on Manufacturing Systems, Saarbrücken, June, 2003.

2. Albizuri, J., Fernandes, M.H., Garitaonandia, I., Hernández, J.M., Sabalza, X., Muñoa, J. (2004). “Obtención de un Modelo Mejorado Espacio-Estado de una Rectificadora sin Centros.” XV Congreso de Máquinas-Herramienta y Tecnologías de Fabricación, San Sebastián, Octubre, 2004 (aceptado para publicación).

420

SP4 Creep Feed Grinding of Ti Alloys Contact Information: Rafael Lizarralde Mechanical Department Ideko, Centro Tecnológico Polígono de Arriaga, 2 – 20870 – Elgoibar Spain Tel:+34 943748000 Fax: +34 943743804 Email: [email protected] http:www.ideko.es Abstract: Development of the technology for conventional and CBN creep feed grinding of Ti alloy parts, used in aeronautics and energy generation turbine parts mainly. Working conditions, dressing strategies, coolant application and machine configuration were the main research topics within this line. The results of this research are already been put into market by Danobat Company.

Key Issues of the Work: • Coolant specification selections for creep feed grinding in continuos dressing • Dressing strategies: continuous dressing. • Machine prototype construction with 75 Kw wheelhead power. • Grinding tests are performed in order to obtain the maximal material flow rate without burn

pieces. Status: Completed in 2002 Publications of this work: 1. Alberdi, R. (2002). “Nuevo Concepto de Rectificadora Plana: Varias Columnas Móviles

frente a una Mesa Móvil”. XIV Congreso de Máquinas-Herramienta y Tecnologías de Fabricación, San Sebastián, Octubre, 2002.

421

SP5 Eco-efficient Grinding Contact Information: Rafael Lizarralde Mechanical Department Ideko, Centro Tecnológico Polígono de Arriaga, 2 – 20870 – Elgoibar Spain Tel:+34 943748000 Fax: +34 943743804 Email: [email protected] http:www.ideko.es Abstract: Investigations towards the decrease of the energy consumed in grinding process. This project is linked with the other industrial and university partners, under the ENGY project. Several lines are being investigated oriented to this objective:

• Grinding strategies: definition of the most efficient working parameters for a minimum waste of energy and materials (wheel, coolant).

• Coolant efficient application. • Coolant efficient processing for a maximum coolant life. • Selection of grinding conditions for a maximum coolant life. Key Issues of the Work: • Influence of grinding particle size of coolant in grinding. • Optimal wheel specifications to decrease specific energy. • Optimal grinding conditions to decrease specific energy, Status: Ongoing. Publications of this work:

422

SP6 Grind Hardening Contact Information: Rafael Lizarralde Mechanical Department Ideko, Centro Tecnológico Polígono de Arriaga, 2 – 20870 – Elgoibar Spain Tel:+34 943748000 Fax: +34 943743804 Email: [email protected] http:www.ideko.es Abstract: To use the heat generated in grinding for hardening the workpiece. One of the critical aspects is the application of a certain refrigeration to the wheel in order to increase it’s life, without interfering in the hardening conditions. Different strategies to apply this cooling effect and solving some other specific problems of grind hardening, such as overlapping in cylindrical parts, have been developed and tested.

Key Issues of the Work: • Influence of cutting conditions in hardened depht. • Overlapping area solution estrategies. • Influence of different coolanta srtategies. • Real industrial aplications. Spiders for drive line transmission for cars. Status: Ongoing. Publications of this work: 1. Lizarralde, R., Minguez, J. M. (1998) "Machine Tool Concept for Integrated Grinding and

Heat Treatment Operations" Proceedings of the International Seminar on Improving Machine Tool Performance, San Sebastian, Spain, July 6 - 8, 1998.

423

SP7 Intelligent Grinding and Dressing Strategies Contact Information: Rafael Lizarralde Mechanical Department Ideko, Centro Tecnológico Polígono de Arriaga, 2 – 20870 – Elgoibar Spain Tel:+34 943748000 Fax: +34 943743804 Email: [email protected] http:www.ideko.es Abstract: Development of monitoring and control strategies for an optimum, minimum energy, time and wheel consumption grinding process. Different strategies are being developed in the monitoring range (internal CNC signals and external sensors) for the identification of dressing need and to optimize the dressing process. Control strategies to obtain maximum efficiency of the grinding process are being developed. Key Issues of the Work: • Monitoring of wheel condition and dressing process by means of different strategies: external

sensors, internal signals. • Intelligent system capable to identify the ranges where wheel requires dressing and dressing

is completed. Status: Ongoing Publications of this work: 1. Mendikute, A., Alberdi, R., Rodríguez, A., de Arriba, A., Uribe-Etxeberria, R. (2004).

“Sistema de Monitorización Integrado en CNC para Ddetección on-line de Necesidades de Diamantado”. XV Congreso de Máquinas-Herramienta y Tecnologías de Fabricación, San Sebastián, Octubre, 2004 (aceptado para publicación).

424

SWEDEN

425

SW1 Application of “Wedge Grinding Technique” (WGT) for Grindability and Surface Integrity Studies Contact Information: Prof. H. Chandrasekaran Swedish Institute for Metals Research Drottning Kristinas väg 48 SE-114 28, Sweden Email: [email protected] http:www.simr.se Abstract: The innovative “Wedge Grinding Technique” (WGT) developed at SIMR was successfully used to investigate the role of a) work materials (mainly tool and high speed steels) and b) grinding wheels (wheel processing, grit size and bond grade) in the context of “thermal damage criterion” in grindability grading. Surface integrity aspects such as microstructure/ phase changes, hardness gradient and residual stress could thus be correlated with grinding conditions from a single test. Key Issues of the Work: • Application of the technique for grading grinding wheels • Correlation of different surface integrity aspects. Status: Completed Publications of this work: H. Chandrasekaran

426

SW2 Grindability Grading of Steels with Special Reference to Thermal Damage Contact Information: Prof. H. Chandrasekaran Swedish Institute for Metals Research Drottning Kristinas väg 48 SE-114 28, Sweden Email: [email protected] http:www.simr.se Abstract: Traditional grindability grading of steels is based on the G ratio. However, in the context of material development specific gradation based on the criterion of thermal damage is required. Towards this an innovative “Wedge Grinding Technique” (WGT) was successfully developed and a number of tool steels were evaluated. This technique was also used as a criterion in modelling form grinding within another European project (FORMGRIND) Key Issues of the Work: • Standardising of the “Wedge Grinding Technique” (WGT) • Measuring the surface temperature during grinding Status: Completed Publications of this work: H. Chandrasekaran

427

SWITZERLAND

428

SD1 Grinding Wheels with Defined Positions of Abrasive Grains Contact Information: Professor Konrad Wegener, Fredy Kuster Institute of Machine Tools and Manufacturing Swiss Federal Institute of Technology Zurich CH 8092 Zurich, Switzerland Email: [email protected] http:www.iwf.mavt.ethz.ch Abstract: Means to avoid the failure of the grinding process because of overheating and thermal damage of the work material, is to introduce sufficient space between the grit, giving enough space for the chips even for long contact areas and optimizing the coolant flow. At the same time the cutting forces are thus reduced, while the load on each single grit is increased, and the material removal rate can be increased. The goal is to develop processes for automatic defined placement of abrasive grains and optimizing the performance of grinding wheels. Also tools for other processes with geometrically undefined cutting edges such as honing tools are thus ameliorated. Key Issues of the Work: • Manufacturing techniques for single layer grinding wheels with defined placement of

abrasive grains • Optimization of tools with geometrically undefined cutting edge Ongoing Publications of this work: 1. Burkhard, G., Rehsteiner, F.: High efficiency abrasive tool for honing. Annals of the CIRP

51/1 (2002) S. 271-274. 2. Burkhard, G.: Spanen mit definiert angeordneten Hartstoffkörnern. Fortschritt – Berichte

VDI, Reihe 2 Nr. 591, VDI – Verlag, Düsseldorf, (2001).

429

SD2 Electro-chemical Truing and Dressing of Grinding Wheels Contact Information: Professor Konrad Wegener, Fredy Kuster Institute of Machine Tools and Manufacturing Swiss Federal Institute of Technology Zurich CH 8092 Zurich Email: [email protected] http:www.iwf.mavt.ethz.ch Abstract: For grinding of hard materials such as ceramics and sintered carbides superabrasives as CBN and diamond are used. Especially with metal bonds, which are superior to other bonds, truing and dressing must be done other than mechanically, for instance by ECDM. Systems for non-mechanical truing are developed and improved for grinding wheels with arbitrary profiles. Key Issues of the Work: • Truing of grinding wheel profiles of arbitrary shape. • ECDM Truing and dressing. Ongoing Publications of this work: 1. Schöpf, M.: ECDM Abrichten metallgebundener Diamantschleifscheiben. Fortschritt –

Berichte VDI, Reihe 2 Nr. 580, VDI – Verlag, Düsseldorf, (2001). 2. Schöpf, M., 2001, ECDM Conditioning of Metal-bonded Diamond GrindingWheels, Annals

of the CIRP, 50/1:125-128.

430

TAIWAN

431

T1 Amorphous Diamond for Dressing Fixed Abrasive Pad Contact Information: Professor Pei-Lum Tso Dept. of Power Mechanical Engineering National Tsing Hua University HsinChu, Taiwan, R. O. C. Tel: 886 3 5742919 Fax: 886-3-5722840 Email: [email protected] Abstract Chemical Mechanical Polishing (CMP) is the enabling technology for making a smooth surface with high flatness for IC fabrication. Usually a diamond pad conditioner is used to scrap off the polishing debris from the pad top. Recently, an alternative planarization process can be achieved by polishing with a "fixed abrasive pad" (FAP). In order to dress bumps on FAP, this paper use an amorphous diamond, a diamond-like carbon deposited by cathode arc system as the dresser for FAP. The amorphous diamond can produce a surface relief that ranges from a few nanometers to about 200 nanometers. With the addition of this dressing step on a rotary platform, FAP can renew its polishing surface 10 to 100 times before the bumps are used up. The pad cost for polishing can be reduced by at least ten folds and make FAP more desirable than slurry pad for silicon wafer manufacturer due to its intrinsic capabilities to produce flatter wafers with high polishing rate. Publications of this work: The 21st International VLSI/ULSI Mutilevel Interconnection Conference. Hawaii, USA.

432


TURKEY

433

TU1 Surface Roughness Investigation in Surface Grinding Affected by Grinding Medium (dry, grinding fluids and air)

Contact Information: Assoc. Prof. Dr. Orhan Cakir and Dr. Erol Kilickap Department of Mechanical Engineering Dicle University 21280 Diyarbakir, Turkey Tel: +90 412 2488403-4 ex:3547 or ex:3553 Fax: +90 412 2488405 Email: [email protected] Email: [email protected] Assoc. Prof. Dr. Cihan Ozel Department of Mechanical Engineering Firat University 23850 Elazig, Turkey Tel: +90 424 2370000-40 Fax: +90 412 Email: [email protected] Abstract: The effects of grinding medium such as dry, the application of cutting fluid and air-mist or various gases on surface roughness are being investigated. First phase of the research was completed and the application of gases is provided promising results. The material was AISI 8620 steel for experimental study. One of the aims in this study is to get information on gas application instead of cutting fluid and eliminate possible problems occurred during cutting fluid application in grinding. Key Issues of the Work: • Comparison of dry and wet surface grinding • Application of gases as cutting fluids Status: Will Completed 2006 Publications of this work: There has been no published paper from this research yet.

434

TU2 Surface Roughness in External Cylindrical Grinding Contact Information: Prof. Dr. Erhan Altan (Supervisior) Department of Mechanical Engineering Yildiz Technical University İstanbul Turkey Tel: +90 212 2597070 Fax: +90 212 2616659 Email: [email protected] Assis. Prof. Dr. Murat Kiyak Department of Mechanical Engineering Yildiz Technical University İstanbul, Turkey Tel: +90 212 2597070 Fax: +90 212 2616659 Email: [email protected] Assis. Prof. Dr. Orhan Cakir Department of Mechanical Engineering Dicle University 21280 Diyarbakir, Turkey Tel: +90 412 2488403-4 Fax: +90 412 2488405 Email: [email protected] Abstract:

The effects of grinding parameters in external cylindrical grinding method on surface roughness are being investigated.

Key Issues of the Work: • Comparison of dry and wet surface grinding • Investigation of relationships between grinding parameters and surface roughness • Examination of material removal rate affecting on surface quality Status: Will Completed 2006 Publications of this work: Paper will be published.

435

UKRAINE

436

UK1 Laser Application For Diamond Composite Tool Manufacturing. Contact information

Prof. Volodymyr S. Kovalenko, Director, Laser Technology Research Institute, Head, Laser Technology & Material Science Dept of the National Technical University of Ukraine "Kiev Polytechnic Institute" Pr. Peremohy 37, 03056,Kiev Ukraine Tel/Fax: 380-44-236-0277 Tel: 380-44-454-9609 (secretary) E-mail: [email protected] [email protected] http://ltmsd.narod.ru http://laser.ntu-kpi.kiev.ua Abstract

The analysis of techniques and problems in manufacturing tool composites containing super hard materials like diamonds and others, is given. The solution to solve these problems based on laser application is proposed. The results of systematic study of diamond composites sintering with laser radiation are discussed. Using mathematical modeling the heat transfer process at high speed laser beam scanning is studied and connections between working conditions and irradiated material characteristics are found. Results of experimental study of laser parameters influence on diamonds strength, their bond wetness and composite materials structure changes are demonstrated. The advantages to use the iron-based alloys as bonding material to manufacture diamond-containing composites are shown.

Key Issues of the Work:

• Study and development of the new technology of diamond composites tools manufacturing;

• Study and developments of means and techniques to improve the quality and precision of diamond tools.

Status 1st part complited 2003 2nd part is due in 2005 Publications 1. The use of laser technology at diamond disk tool manufacturing (V.Kovalenko, M.Novikov,

V. Sorochenko, L.Golovko, V Shepelev), “Superhard materials”, Kiev, #1, 2004, p.52-63. 2. Laser Technology Application for Diamond Tool Manufacturing (V.Kovalenko, L.Golovko,

N. Novikov, A. Shepelev, V. Sorochenko), The Paton Welding Journal), #7, 2004, p.159-164 3. On the possibility of using laser technology for diamond tool manufacturing (V.Kovalenko,

L.Golovko, N.Novikov, A.Shepelev, V.Sorochenko), Journal of Engineering Manufacturing, IME, London, UK, August 2004, vol.218, #B8, p.1029-1036

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USA

438

U1 Control of the Cylindrical Plunge Grinding Process using In-Process Diameter Gage Feedback Contact Information: Professor Thomas R. Kurfess 813 Ferst Drive Georgia Institute of Technology The George W. Woodruff School of Mechanical Engineering Atlanta, GA 30332-0405 USA Tel: 404-894-0301 Fax: 404-894-9342 Email: [email protected]://precision.e.gatech.edu Abstract: This research examines the application of in-process diameter gage information as continuous feedback for control of the cylindrical plunge grinding process. The in-process work piece diameter information is obtained using a commercially available measurement system coupled with custom designed and built signal conditioning. Two different in-process diameter gage feedback control algorithms demonstrate applications of the theory presented. The first algorithm calculates the system deflection of the grinding machine during the grinding process to control the normal force between the grinding wheel and work piece. The second algorithm calculates and controls the radial material removal rate of the process to improve the final diameter and quality of the work piece. A dynamic model of the internal and external cylindrical plunge grinding process is developed to determine appropriate control parameters based upon estimates of grinding process and experimental setup parameters. Experiments compare the two proposed control algorithms with controlled grind power processes associated with high speed dedicated grinding processes common in the bearing industry. The grind power control demonstrates the ability to minimize the cycle time during the rough stage of the grinding cycle. The system deflection control is also able to regulate the cycle time but detecting the beginning of the grind cycle is crucial to the performance of the control. The radial material removal rate control regulates the change in the diameter of the work piece but is better suited to act during the finish stage of the process to enhance the final surface quality and dimensional characteristics. The limiting factor for the two control algorithms implemented in this research is the transport delay associated with the in-process diameter gage feedback and regulating the feed rate override of the motion control system. Key Issues of the Work: • Power control, force control and deflection control of grinding systems. • Adaptive control for grinding. Status: On Going as of 2004 Publications of this work:

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1.

2.

3.

Longanbach, D. L., Kurfess, T. R., “Real-Time Measurement for an Internal Grinding System,” Transactions of the North American Research Institute, Vol. 26, pp. 317-322, May 1998. Longanbach, D. M., Kurfess, T. R., “In-Process Gage Frequency Response Measurement,” Mechatronics, Vol. 11, No. 4, pp. 754-757, June 2001. Longanbach, D. M., Kurfess, T. R., “In-Process Gage Frequency Response Measurement,” Proceedings of The 7th Mechatronics Forum International Conference, September 2000.

440

U2 Process Estimation and Adaptive Control of a Grinding System Contact Information: Professor Thomas R. Kurfess 813 Ferst Drive Georgia Institute of Technology The George W. Woodruff School of Mechanical Engineering Atlanta, GA 30332-0405 Tel: 404-894-0301 Fax: 404-894-9342 Email: [email protected]://precision.e.gatech.edu Abstract: To achieve cost-effective, high quality precision parts, it is important to determine the grinding process dynamics and subsequently control the process. Conventional controllers, not addressing the varying nature of the process, are limited in their capabilities of reducing processing time and can damage parts. A time-varying grinding process model is needed to provide an adaptive, robust controller design appropriate for creating precision surfaces in a timely manner. To this end, a real-time process model relating the material removal rate to measurable process attributes is established. The focus of this research is primarily the grinding of steels. The grinding model development and its parameter identification techniques using multiple sensor input data are discussed. Estimation algorithm parameters are optimized, resulting in a real-time model that is superior to a fixed parameter grinding models in terms of calculating material removal. The real-time process model is implemented in an adaptive controller of the grinding normal force, canceling the grinding process dynamics. The adaptively controlled grinding system demonstrates an ability to provide stable, fast force regulation with less variation than conventional controllers. This is critical in providing force control for use in the reduction of processing time. Experimental results also show an improved surface following capability for fine finishing. Key Issues of the Work: • Power control and force control of grinding systems. • Real-Time, adaptive control for grinding. Status: Completed 2000 Publications of this work: 1.

2.

Kurfess, T.R., Jenkins, H.E., Dorf, R.C., Computer-Aided Design, Engineering, and Manufacturing System Techniques and Applications, Manufacturing Systems Processes Vol. VI¸ chapter on Production of High Quality Parts by the Process of Grinding in Manufacturing Systems, 2001, pp. 3-1 – 3-32, CRC Press, Inc., Boca Raton, FL. Jenkins, H.E. Kurfess, T.R. and Dorf, R.C., “Design of a Robust Controller for a Grinding System,” The IEEE Transactions on Control Systems Technology, Vol. 4, No. 2, pp. 40-49,

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Jenkins, H. E., Ludwick, S. and Kurfess, T. R., “Determination of a Grinding Model,” ASME Journal of Dynamic Systems, Measurement and Control, Vol. 119, No. 2, pp. 289-293, June 1997. Jenkins, H. E. and Kurfess, T. R., “Dynamic Stiffness Implications for a Multi-Axis Grinding System,” Journal of Vibration and Control, August 1997, Vol. 3, No. 3, pp. 297-313. Jenkins, H. E. and Kurfess, T. R., “Adaptive Pole-Zero Cancellation in Grinding Force Control,” The IEEE Transactions on Control Systems Technology, Vol. 7, No. 3, pp. 363-370, May 1999.

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U3 Thermal Effects on Subsurface Damage during the Surface Grinding of Titanium Aluminide

Contact Information: Professor Thomas R. Kurfess 813 Ferst Drive Georgia Institute of Technology The George W. Woodruff School of Mechanical Engineering Atlanta, GA 30332-0405, USA Tel: 404-894-0301 Fax: 404-894-9342 Email: [email protected]://precision.e.gatech.edu Abstract: This research has focused on improving the model for plastic deformation during surface grinding of TiAl. There has been a three-stage approach to achieving this objective: first, material properties were established as a function of temperature; second, temperatures during grinding were evaluated; and third, subsurface plastic deformation was investigated. Using the facilities at Oak Ridge National Laboratory’s High Temperature Materials Lab, several material properties were established as a function of temperature, ranging from room temperature to 800°C: thermal diffusivity (α), specific heat (cp), thermal expansion (TE), thermal conductivity (k), Vickers hardness (Hv), Young’s modulus (E), and Poisson’s ratio (ν). Temperatures during grinding were established theoretically using J.C. Jaeger’s moving heat source theory; numerically using heat transfer principles; and experimentally with an embedded thermocouple technique. The variable properties allowed for the modification of the theoretical subsurface damage model, which was validated using a technique called the bonded interface method. The completion of this research provides valuable information, useful in the introduction of titanium aluminide into new engineering applications. Key Issues of the Work: • Thermal modeling and experimental verification of grinding intermetallic compounds • Measurement of material properties as functions of temperature for TiAl. Status: Completed 2004 Publications of this work: 1.

2.

3.

Stone, W. L., Kurfess, T. R., “Titanium Aluminide – Thermal Diffusivity, Heat Capacitance, and Coefficient of Thermal Expansion as a Function of Temperature,” Transactions of the North American Research Institute, Vol. 30, pp. 417-421, May 2002. Stone, W., Kurfess, T. R., “Grinding Titanium Aluminide: An Experimental Investigation of Subsurface Damage,” Abrasives Magazine, pp. 22-26, Jan/Feb 2004. Stone, W. L., Kurfess, T. R., “Titanium Aluminide – Material Properties as a Function of Temperature,” Proceedings of the Japan - USA Symposium on Flexible Automation, Hiroshima, Japan, Vol. 1, pp. 533-536, July 2002.

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U4 Identification and Control of Grinding Processes for Intermetallic Compounds Contact Information: Professor Thomas R. Kurfess 813 Ferst Drive Georgia Institute of Technology The George W. Woodruff School of Mechanical Engineering Atlanta, GA 30332-0405 USA Tel: 404-894-0301 Fax: 404-894-9342 Email: [email protected]://precision.e.gatech.edu Abstract: Previous study has proposed that the depth of plastic deformation can be used as a parameter to describe the influence of grinding conditions on other physical properties of subsurface layers. Accordingly, the indentation model has been developed to correlate the depth of plastic deformation with the normal component of grinding force. It has been reported that the under certain grinding conditions the depth of plastic deformation does not follow the indentation model. The primary objective of this research is to explain such deviations and to demonstrate that this model can be used to control and predict the depth of plastic deformation. Elements of this research include the development of an open architecture platform to study grinding process, a signal processing algorithm for gap elimination, introducing and implementation of model reference unfalsification and learning concept, development of a mathematical model for grinding γ-TiAl, a comparison between conventional and superabrasive grinding, control and prediction of the depth of plastic deformation, and initiation of one of the first databases for grinding γ-TiAl. This work not only serves as a step toward the use of IMCs in future technology but also serves as a step toward autonomous machining systems using intelligent control and advanced monitoring which is a feature of the future abrasive technology. Key Issues of the Work: • Modeling of subsurface damage for grinding of IMCs. • Adaptive control for grinding. Status: Completed 2002 Publications of this work: 1. Razavi, H. A. Kurfess, T. R., “Real-Time Control of a Reciprocating Surface Grinder using

Unfalsification and Learning Concept,” International Journal of Adaptive Control and Signal Processing Vol. 15, no. 5, pp. 503-518, August 2001.

2. Razavi, H. A., Danyluk, S., Kurfess, T. R., “Force Control Grinding of Gamma Titanium Aluminide,” International Journal of Machine Tools & Manufacture, Vol. 43, pp. 185-191,

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2003. 3. Razavi, H. A., Kurfess, T. R., “Detection of Wheel and Workpiece Contact/Release in

Reciprocating Surface Grinding,” ASME Journal of Manufacturing Science and Engineering, Vol. 125, No. 2, pp. 394-395, May 2003.

4. Nelson L., Razavi, H. A., Kurfess, T. R. and Danyluk. S. “Generating and Modeling Subsurface Damage in Grinding γ-Ti-48Al,” 1999 International Mechanical Engineering Congress and Exposition, MED-Vol 10 Manufacturing Science and Engineering-1999, pp. 467-472, November 1999.

5. Razavi, H. A. and Kurfess, T. R., “Real-Time Force Control of A Grinding Process Using Unfalsification and Learning Concept,” International Mechanical Engineering Congress & Exposition, DSC-Vol 2, pp. 691-696, November 2000.

6. Razavi, H. A. and Kurfess, T. R., “Real-Time Detection of Wheel and Work-Piece Contact/Release in Reciprocating Surface Grinding,” International Mechanical Engineering Congress & Exposition, DSC-Vol 2, pp. 697-705, November 2000.

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U5 Control of Grinding Contact Information: Steven Y. Liang, Morris M. Bryan, Jr. Professor George W. Woodruff School of Mechanical Engineering Georgia Institute of Technology Atlanta, GA 30332-0405, USA Tel: +1-404-894-8164 Fax: +1-404-894-9342 E-mail: [email protected] Abstract: This study designs adaptive, repetitive, and optimal feedback controllers for cylindrical and surface grinding to regulate power and forces so as to maintain a maximum throughput and part performance. Control configurations are tested and evaluated on open architecture cylindrical and pendulum grinding machines. The results show that the controlled system response can be regulated to meet the requirements of time and process specifications, over a wide range of cutting depth and input power reference. Key Issues of the Work: • Model-based open-architecture control structure for grinding machines • Design and real time implementation of adaptive, repetitive, and optimal feedback controls Status: Completed 2003 Publications of this work: 1. Hecker, R. L. and Liang, S. Y., “Power Feedback Control in Cylindrical

Grinding Process,” Proceedings of Symposium on Controls for Manufacturing, ASME-IMECE, Orlando, 2000, DSC-Vol. 69-2, pp. 713-718.

2. Hekman, K. A. and Liang, S. Y., “Force Modeling for Cup Wheel Surface Grinding,” Proceedings of the ASME Manufacturing Science and Engineering Division, pp. 627-635, IMECE, Anaheim, CA, November 16-20, 1998.

3. Hekman, K. A., Hecker, R. L., and Liang, S. Y., “Fixed-Gain and Adaptive Controls for Constraint Power Cylindrical Traverse Grinding,” Proceedings of 6th International Conference on Production Engineering and Design for Development, Cairo, February 2002.

4. Hecker, R. and Liang, S. Y., “Low Feed Control in Plunge Grinding under Friction Effect,” Proceedings of Japan-USA Symposium on Flexible Automation, pp. 61-66, Vol. 1, 2002.

5. Hecker, R. L. and Liang, S. Y., “Power Feedback Control in Cylindrical Plunge Grinding with an Inner Repetitive Position Control Loop,” Proceedings of the 17th IEEE International Symposium on Intelligent Control, Vancouver, Canada, pp. 642-647, 2002

6. Hekman, K., Hecker, R., and Liang, S. Y., “Adaptive Power Control of Cylindrical Traverse Grinding” Proceedings of 3rd International Conference

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on Metal Cutting and High Speed Machining, Metz, France, June 2001. Volume II, pp. 262-264.

7. Hecker, R. and Liang, S. Y., “Open Architecture System for Power Control in Cylindrical Grinding”, Proceedings of Argentinian Congress of Automatic Control Argentinean Conference, International Federation of Automatic Control (IFAC), Buenos Aires, August 31 – September 3, 2004.

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U6 Flatness, Parallelism and Geometry in Grinding Contact Information: Steven Y. Liang, Morris M. Bryan, Jr. Professor George W. Woodruff School of Mechanical Engineering Georgia Institute of Technology Atlanta, GA 30332-0405, USA Tel: +1-404-894-8164 Fax: +1-404-894-9342 E-mail: [email protected] Abstract: These studies examine the methodology of optimizing the feed rate and depth of cut to improve part finish, part form accuracy and process cycle productivity in surface and cylindrical grindings. Chip thickness, surface asperities, and machine compliance models have been incorporated in the optimal and adaptive feedback control loop to pursue minimum cost functions of time and part error specifications. Experimental data have been presented to compare with traditional constant-parameter grinding operations. Key Issues of the Work: • Cost functioning for surface and cylindrical grinding processes • Multi-objective constrained cycle planning and optimization Status: On-going Publications of this Work: 1. Hekman, K. A. and Liang, S. Y. “Flatness Control in Grinding by Depth of

Cut Manipulation,” International Journal of Mechatronics, 8, pp. 323-335, 1998. 2. Hekman, K. A. and Liang, S. Y., “Compliance Feedback Control for Part

Parallelism in Grinding,” International Journal of Advanced Manufacturing Technology, Vol. 15, pp. 64-69, 1999.

3. Hekman, K. A. and Liang, S. Y., “Feedrate Optimization and Depth of Cut Control for Productivity and Part Parallelism in Grinding,” International Journal of Mechatronics, Vol. 9, pp. 447-462, 1999.

4. Hekman, K. and Liang, S. Y., “Improving Part Parallelism and Productivity in Cup Wheel Surface Grinding,” CD Proceedings of Mechatronics Forum, Atlanta, September 2000.

5. Hecker, R. L. and Liang, S. Y., “Cylindrical Grinding Cycle Design based on Final Part Quality Constraints,” CD Proceedings of Symposium on Accuracy and Stability in Machining, Proceedings of IMECE ’03, ASME,

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U7 Modelling of the Grinding Process Contact Information: Steven Y. Liang, Morris M. Bryan, Jr. Professor George W. Woodruff School of Mechanical Engineering Georgia Institute of Technology Atlanta, GA 30332-0405, USA Tel: +1-404-894-8164 Fax: +1-404-894-9342 E-mail: [email protected] Abstract: Analytical, physical, and mathematical models are been established to quantitatively relate process attributes to grinding parameters. These atrributes have included force, power, part finish, part size, and shop floor air quality, while the grinding parameters have incorporated speed, feed, depth of engagement, wheel topography, fluid pressure, and fluid flow rate. The study facilitates the design and optimization of grinding process for the objectives of both productivity and environmental compatibility. Key Issues of the Work: • Stress, temperature, fluid atomization, and chip thickness modeling in grinding • Experimental calibration and validation of the analytical grinding models Status: On-going Publications of this work:

Chen, Z, Yamaguchi, H., and Liang, S. Y., “Predictive Modeling of Cutting Fluid Aerosol in Grinding Process,” Transactions of the North American Manufacturing Research Institution, Society of Manufacturing Engineers, pp. 277-285, 2002.

1.

2.

3.

4.

5.

Hecker, R. L., Ramoneda, I. M., and Liang, S. Y., “Active Grain Density Calculation and Force per Grain Estimation in Grinding,” Transactions of North American Manufacturing Research Institution, Society of Manufacturing Engineering, pp. 281-288, 2003. Hecker, R., Ramoneda, I., and Liang, S. Y., "Analysis of Wheel Topography and Grit Force for Grinding Process Modeling,” Journal of Manufacturing Processes, Society of Manufacturing Engineers, Vol. 5, No. 1, pp.13-23, 2003. Hecker, R. L. and Liang, S. Y., “Predictive Modeling of Surface Roughness in Grinding,” International Journal of Machine Tools and Manufacture, 43, pp. 755-761, 2003. Hecker, R. L. and Liang, S. Y., “Grinding Force and Power Modeling based on Chip Thickness Analysis” accepted by International Journal of Advanced Manufacturing Technology. (in print)

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U8 Fine Grinding of Silicon Wafers Contact Information: ZJ Pei, Ph.D. Assistant Professor Kansas State University Dept of Industrial and Manufacturing Systems Engineering 211 Durland Hall Manhattan, KS 66506 785-532-3436 785-532-3738 fax [email protected] http://www.imse.ksu.edu/~zpei/zpei.html#_top Abstract: The objective of the research is to generate the understanding and knowledge of silicon wafer fine grinding necessary for the development of an innovative wafering process flow. Specifically, the research will develop mathematical models to predict the distance and locus of grinding marks and the effects of the chuck shape on grinding marks, and physical models to explain the generation mechanisms of the deepest subsurface cracks and the self-dressing mechanisms of grinding wheels in silicon wafer fine grinding; and validate these models by experiments.

Status: Ongoing Sponsors: National Science Foundation Advanced Manufacturing Institute of Kansas State University Publications of this work: 1. Pei, Z.J., Fisher, G.R., Bhagavat, M., and Kassir, S., “A grinding-based manufacturing

method for silicon wafers: an experimental investigation,” accepted to appear in International Journal of Machine Tools and Manufacture.

2. Sun, W.P., Pei, Z.J., and Fisher, G.R., “Fine grinding of silicon wafers: effects of chuck shape on grinding marks,” accepted to appear in International Journal of Machine Tools and Manufacture.

3. Sun, W.P., Pei, Z.J., and Fisher, G.R., 2005, “Fine grinding of silicon wafers: machine configurations for spindle angle adjustments,” International Journal of Machine Tools and Manufacture, Vol. 45, No. 1, pp. 51-61.

4. Sun, W.P., Pei, Z.J., and Fisher, G.R., 2004, “Fine grinding of silicon wafers: a mathematical model for the wafer shape,” International Journal of Machine Tools and Manufacture, Vol. 44, No. 7-8, pp. 707-716.

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http://www.imse.ksu.edu/~zpei/zpei.html#_top

U9 Rotary Ultrasonic Machining and Grinding Contact Information: ZJ Pei, Ph.D. Assistant Professor Kansas State University Dept of Industrial and Manufacturing Systems Engineering 211 Durland Hall Manhattan, KS 66506 USA 785-532-3436 785-532-3738 fax [email protected] http://www.imse.ksu.edu/~zpei/zpei.html#_top Abstract: Rotary ultrasonic machining is a hybrid machining process that combines the material removal mechanisms of diamond grinding and ultrasonic machining (USM), resulting in higher material removal rate (MRR) than that obtained in either diamond grinding or USM. Among the non-traditional machining processes being proposed for machining advanced ceramics, such as laser machining, electrical discharge machining, etc., RUM is a relatively low-cost, environment-benign process and easily fits in with the infrastructure of traditional machining environment. The research will study effects of process parameters on MRR, surface roughness, cutting force, and tool wear.

Status: Ongoing Sponsors: Society of Manufacturing Engineers Advanced Manufacturing Institute of Kansas State University Publications of this work: 1. Jiao, Y., Liu, W.J., Pei, Z.J., Xin, X.J., and Treadwell, C., Study on edge chipping in rotary

ultrasonic machining on ceramics: an integration of designed experiment and FEM analysis, accepted in Journal of Manufacturing Science and Engineering.

2. Jiao, Y., Hu, P., Pei, Z.J., and Treadwell, C., Rotary ultrasonic machining of ceramics: design of experiments, accepted in International Journal of Manufacturing Technology and Management.

3. Li, Z.C., Jiao, Y., Deines, T.W., Pei, Z.J., and Treadwell, C., Development of an innovative coolant system for rotary ultrasonic machining, accepted to appear in International Journal of Manufacturing Technology and Management.

4. Hu, P., Zhang, J.M., Pei, Z.J., Treadwell, C., 2002, Modeling of material removal rate in rotary ultrasonic machining: designed experiments, Journal of Materials Processing Technology, Vol. 129, No. 1-3, pp. 339-344.

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U10 Soft-Pad Grinding of Wire-Sawn Silicon Wafers Contact Information: ZJ Pei, Ph.D. Assistant Professor Kansas State University Dept of Industrial and Manufacturing Systems Engineering 211 Durland Hall Manhattan, KS 66506 USA 785-532-3436 785-532-3738 fax [email protected] http://www.imse.ksu.edu/~zpei/zpei.html#_top Abstract: Soft-pad grinding uses fixed abrasive diamond wheels to grind wafers held on a soft pad (instead of rigid chuck). This research aims to advance the understanding and knowledge of wire-sawn wafer grinding on soft pads, and to promote the widespread application of the technology. Finite element simulation will be carried out to develop a fundamental understanding of the soft-pad grinding and its effectiveness in removing the wire-sawing induced waviness, and to generate knowledge of the effects of pad materials and process parameters on waviness removal. Experiments will be performed to validate the finite element model. The understanding and knowledge acquired will provide guidance to overcome the technical barriers that have hindered the widespread application of soft-pad grinding.

Sponsors: National Science Foundation Advanced Manufacturing Institute of Kansas State University Status: Ongoing Publications of this work: 1. Sun, X.K., Pei, Z.J., and Xin, X.J., “Waviness removal in grinding of wire-sawn silicon

wafers: three-dimensional finite element analysis,” accepted to appear in International Journal of Advanced Manufacturing Systems.

2. Pei, Z.J., Kassir, S., Bhagavat, M., and Fisher, G.R., 2004, “An experimental investigation into soft-pad grinding of wire-sawn silicon wafers,” International Journal of Machine Tools and Manufacture, Vol. 44, No. 2-3, pp. 297-304.

3. Sun, X.K., Pei, Z.J., Xin, X.J., and Fouts, M., 2004, "Waviness removal in grinding of wire-sawn silicon wafers: 3D finite element analysis with designed experiments," International Journal of Machine Tools and Manufacture, Vol. 44, No. 1, pp. 11-19.

4. Xin, X.J., Pei, Z.J., and Liu, W.J., 2004, “Finite element analysis on soft-pad grinding of wire-sawn silicon wafers,” Journal of Electronic Packaging, Vol. 126, No. 2, pp. 177-185.

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U11 Mechanics of Compliant Finishing Tools Contact Information: Professor Robert J. Stango Department of Mechanical Engineering Marquette University Milwaukee, Wisconsin 53233 USA Tel: 414 288 6972 Fax: 414 288 7790 Email: [email protected] Abstract: This researcher is involved in the modeling, analysis and design of compliant fixed-abrasive finishing tools such as brushes (filamentary, flap, and ball-hone brushing tools), and non-woven abrasives. Here, the abrasive is embodied in a flexible tool that is subjected to considerable deformation during the material removal operation. Although the deformation of the tool can be large (i.e., large deformation mechanics analysis is necessary for modeling the problem), the tool remains undamaged, because large deflections are incurred within the elastic region of the material system. Applications include deburring, surface decontamination, surface texturing, as well as other finishing operations. Key Issues of the Work: • Brushing tool mechanics analysis. • Brushing too design. • Brushing tool material removal mechanics. Status: Ongoing Selected Publications of this work: 1. Contact Zone Force Profile and Machining Performance of Filamentary Brush, Stango, R.J.,

Cariapa, V., and Zuzanski, M., Transactions of the ASME, Journal of Manufacturing Science and Engineering, in press (2005).

2. Morphology of Metal Surface Generated by Nylon/Abrasive Brush, Overholser, R., Stango, R.J., and Fournelle, R.A., International Journal of Machine Tools and Manufacture, vol. 43, pp. 193-202 (2002).

3. Development of Force Control Model for Edge Deburring with Filamentary Brush, L. Chen, R. J. Stango, and V. Cariapa, Transactions of the ASME, Journal of Manufacturing Science and Engineering, vol. 123, no. 3, pp.528-532, (2001).

4. Automated Deburring with Filamentary Brush: Prescribed Burr Geometry, R. J. Stango, L. Chen, and V. Cariapa, Transactions of the ASME, Journal of Manufacturing Science and Engineering, vol. 121, no. 3, pp.385-392, (1999).

5. Analysis of Contact Mechanics for the Circular Filamentary Brush/Workpart System: Solution Method and Numerical Studies, C.Y. Shia, R.J. Stango, and S.M. Heinrich, Transactions of the ASME, Journal of Manufacturing Science and Engineering, vol. 120, no. 4, pp.715-721, (1998).

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6. Analysis of Filament Deformation for a Freely Rotating Cup Brush, R.J. Stango and C.Y. Shia, Transactions of the ASME, Journal of Manufacturing Science and Engineering, vol. 119, no. 3, pp. 298-306, (1997).

7. Analysis of Complaint Honing Tool for Brushing of Cylindrical Surface, C.Y. Shia and R.J. Stango, Transactions of the ASME, Journal of Manufacturing Science and Engineering, vol. 119, no. 3, pp.441-444, (1997).

8. Development of a Rational Basis for Design of Advanced Brushing Tools, R.J. Stango, C.Y. Shia, and J.A. Henderson, Transactions of the ASME, Journal of Engineering for Industry, vol. 115, no. 3, pp. 308-315, (1994).

9. On the Frictional Response of Circular Filamentary Brush in Contact with Planar Workpart, C. Y. Shia, R. J. Stango, International Journal of Machine Tools and Manufacture, vol. 34, no. 4, pp. 573-589, (1994).

10. Aspects of Process Model for Automatic Control of Edge-Deburring with Filamentary Brush, V. Cariapa, R. J. Stango, and L. Chen, Journal of Engineering for Industry, vol. 114, no. 3, pp. 294-300, (1992).

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U12 Wheel Loading Causes and Solutions Contact Information: John W. Sutherland, Ph.D. Richard & Elizabeth Henes Chair Professor Dept. of Mechanical Engineering-Engineering Mechanics Michigan Technological University 1400 Townsend Drive Houghton, MI USA 49931 Phone: 906-487-3395 Fax: 906-487-2822 email: [email protected]://www.me.mtu.edu/~jwsutherhttp://www.mfg.mtu.edu/ Abstract

Wheel loading severely limits grinding wheel effectiveness; it leads to higher grinding energies, greater wheel wear rates, and deterioration of surface finish. Loading occurs when chips accumulate in the spaces between grits. A number of adhesion theories (physical adsorption, chemical bonding, diffusion, etc.) have been considered for their role in wheel loading. From experiments, the significant role of temperature in wheel loading has been demonstrated. The effects of chip size distribution and friction coefficient are being investigated. With an understanding of the causes of wheel loading, solutions to reduce it can be developed. These might include some form of agitation (such as from vibration assistance) or alternative coolant chemistries. Key Issues of the Work:

• The application of adhesion theories to wheel loading • Measurement of chip size distribution using image analysis software

Status: On-going Publications of this Work: 1. Zhang, P. and M. H. Miller, “Investigation of Wheel Loading Based on Adhesion Theories

and Temperature,” Proc. of the ASPE Annual Meeting, 2004. 2. Zhang, P. and M. H. Miller, “Grinding Wheel Loading with and without Vibration

Assistance,” Proc. of the ASPE Annual Meeting, 2003.

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http://www.me.mtu.edu/%7Ejwsuther

http://www.mfg.mtu.edu/

U13 Geometric Modeling of Ground Surface Generation Contact Information: John W. Sutherland, Ph.D. Richard & Elizabeth Henes Chair Professor Dept. of Mechanical Engineering-Engineering Mechanics Michigan Technological University 1400 Townsend Drive Houghton, MI, USA 49931 Phone: 906-487-3395 Fax: 906-487-2822 email: [email protected]://www.me.mtu.edu/~jwsutherhttp://www.mfg.mtu.edu/

Abstract

To produce ground parts with desirable surface properties, it is necessary to understand the evolution of these characteristics through the surface generation mechanisms of the grinding process. Computer simulations have been developed that predict ground surface texture based on wheel texture and grinding conditions. The simulations have been used to analyze the effect of specific frequency components in the wheel surface. In addition, the effects of vibratory modulation on surface texture and chip size distribution have been studied. Key Issues of the Work:

• Accurate measurement of wheel surface texture • Frequency domain modeling of surface texture to reduce model size • Development of high frequency vibratory workpiece holder

Status: Completed Publications of this Work: 1. Salisbury, E. J., K. V. Domala, K. S. Moon, M. H. Miller and J. W. Sutherland, “A Three

Dimensional Model for the Surface Texture in Surface Grinding, Part 1—Surface Generation Model,” ASME Journal of Mfg Sci. and Engineering, Vol. 123, No. 4, 2001, pp. 576-581.

2. Salisbury, E. J., K. V. Domala, K. S. Moon, M. H. Miller and J. W. Sutherland, “A Three Dimensional Model for the Surface Texture in Surface Grinding, Part 2—Grinding Wheel Model,” ASME Journal of Mfg Sci. and Engineering, Vol. 123, No. 4, 2001, pp. 582-590.

3. Miller, M. H. and T. A. Dow, “Influence of the Grinding Wheel in the Ductile Grinding of Brittle Materials: Development and Verification of Kinematic Based Model,” ASME Journal of Mfg Sci. and Engineering, Vol. 121, No. 4, 1999, pp. 638-646.

4. Wang, Y., K. S. Moon and M. H. Miller, “A New Method for Improving the Surface Grinding Process,” International Journal for Manufacturing Science and Production, Vol. 1, No. 3, 1998, pp. 159-167.

5. Miller, M. H. and K. S. Moon, “The Effect of Workpiece Modulation on Grinding Kinematics,” Proc. of the ASPE Spring Topical Meeting, 1996, pp. 70-75.

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U14 Intermittent Grinding Processes for Hard Steels and Ceramics Contact Information: John W. Sutherland, Ph.D. Richard & Elizabeth Henes Chair Professor Dept. of Mechanical Engineering-Engineering Mechanics Michigan Technological University 1400 Townsend Drive Houghton, MI USA 49931 Phone: 906-487-3395 Fax: 906-487-2822 email: [email protected]://www.me.mtu.edu/~jwsutherhttp://www.mfg.mtu.edu/ Abstract

Grinding can be turned into an intermittent process by using segmented wheels or by adding vibration assistance. Experiments have shown the following beneficial effects: reduced forces and temperatures, improved wheel condition, and reduction in sub-surface damage (for brittle materials). These effects may be particularly important when grinding hard materials if they can lead to reduced coolant usage and lower rates of wheel wear. Each of these effects has been investigated in an attempt to understand the underlying mechanisms. For example, the effect of intermittent contact on the average friction force has been analyzed. The effect of loading and unloading on subsurface damage has been measured and predicted. With an improved understanding of what causes the beneficial effects, optimal wheel segment geometries or vibration conditions can be selected. Key Issues of the Work: • Force model for intermittent grinding • Force and temperature measurements during intermittent grinding processes • Fracture mechanics modeling of periodic loading and unloading on brittle materials • Measurement of subsurface damage Status: On-going Publications of this Work: 1. Mahaddalkar, P. M. and M. H. Miller, “Force and Temperature Measurements in Vibration

Assisted Grinding,” Proc. of ASPE Annual Meeting, 2002, pp. 515-520. 2. Qu, W., K. Wang, M. H. Miller, Y. Huang and A. Chandra, “Using Vibration Assisted

Grinding to Reduce Subsurface Damage,” Precision Engineering, Vol. 24, No. 4, 2000, pp. 329-337.

3. Chandra, A., K. Wang, Y. Huang, G. Subhash, M. H. Miller and W. Qu, “Role of Unloading in Machining of Brittle Materials,” ASME Journal of Mfg. Sci. and Engineering, Vol. 122, No. 3, 2000, pp. 452-462.

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U15 Wear and Self-Dressing of Resin Bound Grinding Wheels Contact Information: John W. Sutherland, Ph.D. Richard & Elizabeth Henes Chair Professor Dept. of Mechanical Engineering-Engineering Mechanics Michigan Technological University 1400 Townsend Drive Houghton, MI USA 49931 Phone: 906-487-3395 Fax: 906-487-2822 email: [email protected]://www.me.mtu.edu/~jwsutherhttp://www.mfg.mtu.edu/ Abstract

Wheel performance tends to deteriorate over time without some form of dressing. With a model of the self-dressing process, self-dressing wheels could more easily be designed and specified. The self-dressing process for resin bound diamond abrasive wheels has been investigated using measurements of grinding force and grit wear. A technique for measuring grit wear was developed; it involves replication of the wheel surface using a dental molding material and stereo SEM imaging to obtain grit volume information. Based on force and volume change data, G ratios and wear coefficients were calculated. Key Issues of the Work:

• SEM measurement of wear of individual grits • Characterization of grit wear mechanisms (fracture versus attritious) • Characterization of grit sharpness and its relationship to machining force • Prediction of force necessary to fracture grit or cause “pull-out” from binder

Status: On-going Publications of this Work: 1. Handigund, P. B. and M. H. Miller, “Abrasive Wear and Forces in Grinding of Silicon Carbide,” Proc.

of the ASPE Annual Meeting, 2001, pp. 413-416. 2. Miller, M. H. and T. S. Kakumanu, “Investigation of the Self-Dressing of Resin Bound Grinding

Wheels,” Proc. of the 1999 ASME IMECE, MED-Vol. 10, 1999, pp. 493-498.

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U16 An Investigation of High Speed Grinding with Electroplated Diamond Wheels Contactct Information: Ivester, Robert W. Dr. NIST 100 Bureau Drive, Stop 8223 Gaithersburg, MD 20899-8223 phone: (301) 975-8324 email: [email protected] Abstract : An investigation was undertaken to evaluate the effect of high wheel speeds for grinding of silicon nitride ceramic with electroplated diamond wheels. Straight surface grinding experiments were conducted at wheel speeds of 85 m/s and 149 m/s using the same removal rate. Measurements are reported for the grinding forces, radial wheel wear, and surface roughness throughout the useful wheel life, and for the flexure strength after grinding. Although the forces tended to be somewhat lower at the higher wheel speed, the grinding performance was not necessarily better when compared in terms of wheel wear, surface roughness, and strength degradation. Preliminary measurements of acoustic emission illustrate possibilities for process monitoring. An increase of the wheel speed from 85 m/s to 149 m/s resulted in a smaller grinding force, but an increase in wheel wear. A single-valued relationship between radial wheel wear and sliding distance suggests that a faster wheel speed corresponding to a longer sliding distance is responsible for more wheel wear. Strength degradation was found for transverse grinding but not for longitudinal grinding. Wheel speed had almost no effect on the surface roughness and strength degradation. Preliminary results of acoustic emission monitoring showed a proportional relationship between grinding power and AE energy. Key Issues of the Works: • During grinding of silicon nitride ceramic with electroplated wheels, the grinding forces and

power progressively increased and the surface roughness decreased. Status: Completed Publications of this Work: 1. T. W. Hwang, C. J. Evans and S. Malkin, An Investigation of High Speed Grinding with

Electroplated Diamond Wheels, Annals of CIRP, Vol:49/1/2000, pp.245-248, Sydney.

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U17 On the Mechanics of the Grinding Process – Stochastic Nature of the Grinding Process Contact Information: Prof. Ranga Komanduri Oklahoma State University Mechanical and Aerospace Engineering 218 Engineering North Stillwater OK 74078, USA Tel: +1 405 744 5900 Fax: +1 405 744 7873 Email: [email protected] Abstract: Grinding of metals is a complex material removal operation involving cutting, ploughing, and rubbing depending on the extent of interaction between the abrasive grains and the workmaterial under the conditions of grinding. It is also a stochastic process in that a large number of abrasive grains of unknown geometry, whose geometry varies with time, participate in the process and remove material from the workpiece. Also, the number of grains passing through the grinding zone per unit time is extremely large. To address such a complex problem, it is necessary to analyze the mechanics of the grinding process using probability statistics, which is the subject of this investigation. Such an analysis is applicable to both form and finish grinding (FFG), such as surface grinding and stock removal grinding (SRG), such as cut-off operation. In this investigation, various parameters of the process including the number of abrasive grains in actual contact, the number of actual cutting grains per unit area for a given depth of wheel indentation, the minimum diameter of the contacting and cutting grains, and the volume of the chip removed per unit time were determined analytically and compared with the experimental results reported in the literature. Such an analysis enables the use of actual number of contacting and cutting grains in the grinding wheel for thermal and wheel wear analyses. It can also enable comparison of analytical work with the experimental results and contribute towards a better understanding of the grinding process. The analysis is applied to some typical cases of fine grinding and cut-off operations reported in the literature. It is found that out of a large number of grains on the surface of the wheel passing over the workpiece per second (-million or more per second), only a very small fraction of the grains merely rub or plough into the workmaterial (-3.8% for FFG and -18% for SRG) and even a smaller fraction (-0.14% for FFG and -1.8% for SRG) of that participate in actual cutting, thus validating Hahn's rubbing grain hypothesis Status: Ongoing Publications of this work: 1. Hou, Z. B. and R. Komanduri, "On the Mechanics of the Grinding Process-Part 1 Stochastic

Nature of the Grinding Process," Int. J of Machine Tools and Manufacturing, 43 (2003) 1579-1593

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U18 On the Mechanics of the Grinding Process, Part II—Thermal Analysis of Fine Grinding Contact Information: Prof. Ranga Komanduri Oklahoma State University Mechanical and Aerospace Engineering 218 Engineering North Stillwater OK 74078, USA Tel: +1 405 744 5900 Fax: +1 405 744 7873 Email: [email protected] Abstract: Thermal analysis of fine grinding is conducted taking into consideration the stochastic nature of the distribution of abrasive s and its role under fine grinding (dry) conditions to determine the grinding temperatures and the heat partition at the contacting interface. The analysis considers the grain-workpiece interactions at the local level and the wheel-workpiece interactions at the global level. The workpiece temperature in the grinding zone is taken as the sum of the background temperature due to distributed action of all the previous active grains operating in the grinding zone (global thermal analysis) and the localized temperature spikes experienced at the current abrasive grain tip-workpiece interfaces (local thermal analysis), similar to the work reported in the literature. Since the Peclet number, Npe, in the case of fine grinding is very high (a few hundred), the heat flow between the work and the contacting abrasive grains can be considered to be nearly one-dimensional. In this paper, we consider the interaction between an abrasive grain and the workpiece at the contact interface. Consequently, the heat source relative to the grain is stationary and relative to the workpiece is fast moving. The interface heat source on the grain side as well as on the work-side is equivalent to an infinitely large plane heat source (with the same heat liberation intensity as the circular disc heat source). However, it will be shown in the paper that the contacting times are different. For example, the abrasive grain contacts at source, as it moves over the interface, for a longer period of time (-milliseconds) whereas the workpiece contacts the heat source for a shorter period of time (~a few microseconds). The equivalent thermal model developed in the present investigation is simple and represents the process more realistically, especially the heat partition. The analytical results reported here are found to good agreement with both the analytical and experimental results reported in the literature by other researchers. Status: Ongoing Publications of this work: 1. Hou, Z. B. and R. Komanduri, "On the Mechanics of the Grinding Process- Part 2 Thermal

Aspects of Fine Grinding Process," Int. J of Machine Tools and Manufacturing 44 (2004) 247-270

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U19 On the Mechanics of the Grinding Process-Part 3 Thermal Aspects of the Abrasive Cut-off Process

Contact Information: Prof. Ranga Komanduri Oklahoma State University Mechanical and Aerospace Engineering 218 Engineering North Stillwater OK 74078, USA Tel: +1 405 744 5900 Fax: +1 405 744 7873 Email: [email protected] Abstract: Heat generated in the abrasive cut-off operation can affect the life of resin bonded grinding wheels and cause thermal damage to the workpiece. Thermal analysis of the abrasive cut-off operation can, therefore, provide guidelines for proper selection of the grinding conditions and optimization of the process parameters for improved wheel life and minimal thermal damage to the workpiece. In this investigation, a new thermal model of the abrasive cut-off operation is presented based on statistical distribution of the abrasive grains on the surface of the wheel. Both cutting and ploughing/rubbing that take place between the abrasive grains and the work material are considered, depending on the depth of indentation of the abrasives into the work material. In contrast to the previous models, where the apparent contact area between the wheel and the workpiece was taken as the heat source, this model considers the real area of contact, namely, the cumulative area of actual contacting grains present at the interface as the heat source. It may be noted that this is only a small fraction of the total contact area as only a small percentage of the abrasive grains present on the surface of the cut-off wheel are in actual contact with the workpiece at any given time and even a smaller fraction of them are actual cutting grains taking part in the cut-off operation. Since, the Peclet number, Npe in the case of cut-off grinding is rather high (a few hundred), the heat flow between the work and the contacting abrasive grains can be considered to be nearly one-dimensional. In this paper, we consider the interaction between an abrasive grain and the workpiece at the contact interface. Consequently, the heat source relative to the grain is stationary and relative to the workpiece is fast moving. The interface heat source on the grain side as well as on the workpiece side is equivalent to an infinitely large plane heat source with the same heat liberation intensity as the circular disc heat source. However, it will be shown in the paper that the contacting times are different. For example, the abrasive grain contacts the heat source, as it moves over the wheel-work interface, for a longer period of time (~ milliseconds) whereas the workpiece contacts the heat source for shorter period of time (~ a few microseconds). The temperature in the grinding zone is taken as the sum of the background temperature due to the distributed action of the previous active grains operating in the grinding zone (global thermal analysis) and the localized temperature spikes experienced at the current abrasive grain tip-workpiece interfaces (local thermal analysis), similar to the work reported in the literature [Proc Roy Soc (London) A 453 (1997) 1083]. The equivalent thermal model developed in e present investigation is simple and represents the process more realistically, especially the heat partition. The model developed provides a better

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appreciation of the cut-off operation; a realistic estimation of the heat partition between the wheel, the workpiece, and the chip; thermal gradients in the workpiece due to abrasive cut-off operation, and an insight into the wear of the cut-off wheels. Status: Ongoing Publications of this work: 1. Hou, Z. B. and R. Komanduri, "On the Mechanics of the Grinding Process-Part 3 Thermal

Aspects of the Abrasive Cut-off Process," Int. J of Machine Tools and Manufacturing 44 (2004) 271-289

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U20 Ultra-precision Grinding Contact Information: Professor Eric Marsh Dept. of Mechanical Engineering Pennsylvania State University University Park, PA 16802, USA Email: [email protected]: www.me.psu.edu/mdrl Abstract: Forces generated during precision grinding are small and present challenges for accurate and reliable process monitoring. These challenges are met by incorporating non-contact displacement sensors into an aerostatic spindle that are calibrated to measure grinding forces from changes in the gap between the rotor and stator. Four experiments demonstrate the results of the force-sensing approach in detecting workpiece contact, process monitoring with small depths of cut, detecting workpiece defects, and evaluating abrasive wheel wear/loading. Results indicate that force measurements are capable of providing useful feedback in precision grinding with excellent contact sensitivity, resolution, and detection of events occurring within a single revolution of the grinding wheel. Key Issues of the Work: • Real time process monitoring • Force measurement

Status: On-going Publications of this work: 1. E.R. Marsh, R.D. Grejda, and B.R. Knapp. 2000. Superabrasive Grinding Process

Optimization Through Force Measurement, Abrasives Magazine, pp. 29-33 2. J. A. Couey, E. R. Marsh and B. K. Knapp. Accepted 2004. A Comparison of Force and

Acoustic Emission Sensors in Monitoring Precision Cylindrical Grinding, ASPE Journal of Precision Engineering.

3. J.A. Couey, E.R. Marsh, R.R. Vallance. 2004. A Comparison of Force and Acoustic Emission Sensors in Monitoring Precision Cylindrical Grinding, American Society for Precision Engineering (ASPE) 2004 Annual Meeting, Orlando, FL, October 24-29, 2004.

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http://www.me.psu.edu/mdrl

U21 Dynamic Simulation Models of Chatter Prediction in Grinding Processes Contact Information: Professor Yung C. Shin School of Mechanical Engineering Purdue University USA Email: [email protected] http:widget.ecn.purdue.edu/~simlink Abstract: Many grinding processes are susceptible to chatter. Due to the complexity of grinding processes, the mechanics of chatter during grinding processes is not well understood. A systematic dynamic model has been developed to predict grinding chatter in terms of various operating parameters. The model can predict stable (or unstable) regions, surface topography and vibration amplitude. Key Issues of the Work: • Mechanistic modeling of grinding processes • Three dimensional dynamics with multiple degrees of freedom • Mechanism of regenerative chatter Status: On-going Publications of this work: 1. Li, H. and Shin, Y.C., “A Time-domain Dynamic Model for Chatter Prediction of Cylindrical

Grinding Processes”, submitted for publication in Trans. ASME, Journal of Manufacturing Science and Engineering.

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U22 Intelligent Optimization of Grinding Processes Contact Information: Professor Yung C. Shin School of Mechanical Engineering Purdue University USA Email: [email protected] http:widget.ecn.purdue.edu/~simlink Abstract: An intelligent grinding optimization methodology has been developed. The scheme utilizes knowledge in the form of generalized grinding models, empirical data and heuristic rules, and provides, through a systematic inferencing method, optimal operating conditions for various grinding processes without violating any of the constraints imposed on the grinding system. Using the Generalized Intelligent Grinding Advisory System, which is the software developed to implement this methodology, large-scale implementations of the methodology at industrial sites and model base development are currently under way. Key Issues of the Work: • Generalized grinding process models for various grinding process conditions • Autonomous learning of grinding processes • Establishment of model parameters for various grinding processes and wheel-work

combinations • Intelligent optimization strategy Status: On-going Publications of this work: 1. Lee, C.W. and Shin, Y.C., “Modeling of Complex Manufacturing Processes by Fuzzy Basis

Function Networks With Application to Grinding Processes”, Trans. ASME, Journal of Dynamic Systems, Measurement and Control, to appear in December, 2004.

2. Shin, Y.C., Lee, C.W. and Choi, T., “Intelligent Grinding Advisory System”, Proc. of the International Grinding Conference, April 4-9, 2003, Itasca, Illinois.

3. Lee, C.W., Choi, T.J., Shin, Y.C., “Intelligent Model-based Optimization of the Surface Grinding Process for Heat-Treated 4140 Steel Alloys with Aluminum Oxide Grinding Wheels,” Transactions ASME, Journal of Manufacturing Science and Engineering, Vol. 125, pp. 65-76, February 2003.

4. Lee, C.W., Choi, T.J. and Shin, Y.C., “Intelligent Modeling of Complex Manufacturing Processes Using Hierarchical Fuzzy Basis Function Networks”, ASME IMECE, DSC24590, CD Vol. 2, Nov. 2001, New York, NY.

5. Lee, C.W. and Shin, Y.C., “Evolutionary Modeling and Optimization of Grinding Processes” International Journal of Production Research, 2000, Vol. 38, No. 12, pp. 2787-2813, 2000.

6. Lee, C.W. and Shin, Y.C., “Improved Generalized Grinding Advisory System”, Proceedings of the ASME Manufacturing Science and Engineering, MED-Vol. 10, pp. 473-480, ASME IMECE, Nov. 1999, Nashville, TN.

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U23 Laser-assisted Dressing and Truing of Superabrasive Wheels Contact Information: Professor Yung C. Shin School of Mechanical Engineering Purdue University USA Email: [email protected] http:widget.ecn.purdue.edu/~simlink Abstract: Dressing and truing of superabrasive wheels such as diamond and CBN wheels present difficulties and contribute to the high cost of grinding with super-abrasive wheels. Laser-assist dressing has been developed to significantly improve dressing and truing performance for superabrasive wheels. Localized heating weakens the bonding material and simultaneous dressing/truing by a mechanical dresser significantly reduces dresser wear and material removal rates. Key Issues of the Work: • Thermal control during laser-assisted dressing • Single point vs. rotary dressing • Performance evaluation of laser-assisted dressed wheels • Optimization of laser-assisted dressing parameters Status: On-going Publications of this work: 1. Shin, Y.C. and Tian, Y., “Laser-assisted Dressing of Vitrified CBN Grinding Wheels”, Proc. of

the International Grinding Conference, April 4-9, 2003, Itasca, Illinois, SME Technical Paper MR03-260.

2. Zhang, C. and Shin, Y.C., "A Novel Laser-assisted Truing and Dressing Technique for Vitrified CBN Wheels", International Journal of Machine Tools and Manufacture, Vol. 42, Issue 7, pp. 825-835, 2002.

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U24 Monitoring and Control of Grinding Processes Contact Information: Professor Yung C. Shin School of Mechanical Engineering Purdue University USA Email: [email protected] http:widget.ecn.purdue.edu/~simlink Abstract: Monitoring and control of various grinding process conditions are critical to maintaining desired grinding conditions. The study focuses on developing monitoring schemes for chatter, wheel wear and surface burning during surface and cylincrical grinding processes and control schemes that will autonomously regulate grinding process variables to maintain desired process conditions. An autonomous feature recognition scheme along with pertinent signal processing techniques and a multi-variate adaptive control method are under development. Key Issues of the Work: • Wheel wear monitoring by acoustic emission • Chatter monitoring based on wavelet transformation of force and vibration signals • Surface burning monitoring by acoustic emission • Autonomous feature extraction from the sensor signals • Multi-variate adaptive control scheme without Status: On-going Publications of this work: 1. Shin, Y.C., Lee, C.W., Choi, T.J. and Hu, S., “Intelligent Control via Open Architecture

Controller”, Proceedings of the 3rd International Machining and Grinding Conference, pp. 257-272, Oct. 4-7, 1999.

2. Lee, C.W. and Shin, Y.C., “Intelligent Modeling and Control of Computer Hard Disk Grinding Processes", Proceedings of the 3rd International Conference on Intelligent Processing and Manufacturing of Materials, July 29-Aug. 2, 2001, Vancouver, British Columbia, Canada.

3. Vishnupad, P., Shin, Y.C. and Shih A., "Monitoring of Internal Plunge Grinding Processes", Proc. of the 1st International Machining & Grinding Conference, pp. 351-371, MR95-179, Dearborn, Michigan, Sept. 12-14, 1995.

4. Shin, Y.C. and Oh, S.J., "Surface Roughness Measurement by Ultrasonic Sensing for In-process Monitoring", ASME DSC-Vol. 50, Symp. on Computer Control Machines for Manufacturing, Dec. 1993, pp. 3-12, New Orleans, LA.

5. Choi, T.J. and Shin, Y.C., “On-line Chatter Detection Using Wavelet-Based Parameter Estimation", Transactions ASME, Journal of Manufacturing Science and Engineering, Vol. 125, pp. 21-28, February 2003.

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U25 Evaluation of Factors Controlling CBN Abrasive Selection for Vitrified Bonded Wheels Contact Information: M. Hitchiner, Technology Manager Saint-Gobain Abrasives 27588 Northline Rd Romulus, MI 48174 USA. Tel: +1 734 941 1388 ext 126 Fax: +1 734 941 2948 Email: [email protected] Abstract: A grinding wheel evaluation study was carried out at Oak Ridge National Laboratory (ORNL), as part of a broader program for an abrasive tool manufacturer, to investigate the impact of new tougher CBN grains becoming available in the commercial market from global sources. The study investigated the effect of grit size distribution and toughness in standard and newly developed bond systems. Through extensive grinding tests, tougher grits were found to require the development of stronger, more resilient bonds to obtain economic benefit. The impact of process variables such as system imbalance was also observed. It was found that micron levels of imbalance or wheel out-of-roundness could significantly impact wheel life. The study has allowed the abrasive tool manufacturer to move forward into the marketplace with improved wheel life and productivity. Status: Completed 2003 Publications of this work: 1. M. Hitchiner, and S. McSpadden, Evaluation of Factors Controlling CBN Abrasive Selection

for Vitrified Bonded Wheels, 6th International Symposium on Advances In Abrasive Technology (ISAAT), Bristol, UK, 2003.

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U26 Develop An Intelligent System That Uses Techniques Of Soft Computing And Artificial Intelligence To Learn, Control, Monitor, And Optimize A Variety Of Complex Precision-Grinding Processes Without Resorting To Trial And Error.

Contact Information: Dr. Anil Srivastava TechSolve, Inc. 6705 Steger Drive Cincinnati, OH 45237-3097 USA Email: [email protected] Abstract: To tackle the challenge of making costly precision-grinding processes more efficient, TechSolve (industrial researcher), Delphi Energy and Chassis Systems (end user of grinding technologies), Applied Grinding Technologies (systems consultant), Purdue University (academic researcher), and Landis Gardner (machine tool builder) plan to pool their resources and particular proficiencies. In this joint venture, the companies propose to develop an automated system that uses techniques of artificial intelligence to learn, control, monitor, and optimize a variety of complex precision-grinding processes without resorting to trial and error. The objective of this three-year project is to produce and validate a "smart" grinding machine that can serve as a highly cost-effective surrogate for scarce human capital. The machine, designed to be modular and portable, will work as a unified system of hardware, sensors, and software that incorporates fuzzy logic, genetic algorithms, and neural networks. Incorporating an assortment of analytical models of grinding processes into a single, well-integrated system has yet to be accomplished and poses a serious technical risk. The economic benefits of optimized grinding processes include increased productivity, reduced expenditure on conventional and super-abrasive grinding wheels, lower rates of improperly machined components, scrap reduction, and improved quality. Cost savings to U.S. grinding operations are estimated to be 10 percent, or $1 billion annually. The initial application will be in the automotive industry. However, this intelligent grinding technology has the potential to fortify the competitiveness of U.S. industries specializing in machine tools and manufacturing technologies.

Active Project Participants are: DELPHI, Energy & Chassis Systems (Dayton, OH); Applied Grinding Technologies (Wixom, MI); Purdue University (West Lafayette, IN); Landis Gardner (Waynesboro, PA); TechSolve (Cincinnati, OH). The Project duration is: 10/2003 - 9/2006, at a total project cost of (est.): $6M Publications of this Work: None to date

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U27 Morphological Modification in Laser-dressed Alumina Grinding Wheels for Microscale High Speed Grinding

Contact Information: Dr. Narendra B. Dahotre Professor and Chairman, Center for Laser Applications Department of Materials Science & Engineering The University of Tennessee Space Institute 10521 Research Drive, Suite 400 Knoxville, TN 37922 USA Tel: (865) 974-0523; Fax: (865) 974-0530 E-mail: [email protected] or [email protected] Abstract: Laser was explored as a non-conventional dressing tool for superabrasive grinding wheels. High power, continuous wave, fiber optically delivered, Nd:YAG laser was employed to dress alumina grinding wheels with varying laser powers. Post laser dressing pole-figure analysis indicated evolution of planar crystallographic textures in the particles of re-solidified surface layer. Evolution of refined, and preferably oriented crystallographic planes resulted in formation of individual particles (grains) with sharp vertices and edges. The surface roughness of the dressed wheel was a manifestation of the new morphologically laser modified surface. This modification in morphological features on surface helps maintain a very high grinding efficiency. The performance of the laser-dressed grinding wheel was evaluated in comparison to the undressed wheel for a plain carbon steel pin using high-speed grinding apparatus. The weight loss in the laser-dressed grinding wheels processed at different powers is low as compared to undressed wheel after grinding. High-speed microscale grinding can be done very efficiently using the laser-dressed wheels to produce a smooth surface finish on the workpiece material Key Issues of the Work: Status: Ongoing Publications of this work: 1. M. J. Jackson, G. M. Robinson, N. B. Dahotre, A. Khangar, and R. Moss, Laser Dressing of

Vitrified Aluminium Oxide Grinding Wheels, Journal of the Institute of Materials, Minerals, and Mining – British Ceramic Transactions (2003), 102, 237-245. ISSN 0967-9782.

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U28 Continuous Dress Creep-Feed Grinding Contact Information: Dr. Changsheng Guo Department of Physical Sciences United Technologies Research Center 411 Silver Lane East Hartford, CT 06108 USA Email: [email protected]:www.utrc.utc.com Abstract: Continuous-Dress Creep-Feed (CDCF) grinding process is widely used in grinding root profiles of turbine blades made of various nickel-base alloys. Typically, the blades are ground to the required forms from casting in two passes with the roughing pass removing most of the stock and leaving about 20 to 50 microns for finishing. Due to the complex dresser-wheel-workpiece interactions in CDCF form grinding, process optimization to reduce cycle time and wheel consumption has been limited to trial-and-error approaches and/or past experiences. Thermal damages to the ground surface and coating cracks on the airfoils are usually the limiting factors to increase productivity. We developed an approach of minimizing cycle time and/or wheel consumption by optimizing process parameters such as workspeed, dress infeed, and dress ratio based on grinding models and in-process power monitoring. Heat flux and surface temperatures are kept below the fluid burnout limits determined from the thermal models to avoid thermal damages to the ground surface. The grinding forces are controlled below the allowable values, which are obtained using a finite element model based on the allowable strain, to avoid coating cracks caused by excessive strain on the blade surface. By implementing this approach, 40% cycle time reduction has been demonstrated while maintaining both the heat flux and grinding forces below the critical values and those obtained under the current production processes. Process monitoring and control of CDCF form grinding using model-based simulation and in-process power measurement is another aspect of the research with the focus on the application of the technology in grinding of turbine blade root serrations. After establishing the optimum process by utilizing the variable-feed approach, whereby both the dress infeed and part feed rate are adaptively varied to minimize cycle time while maintaining the force and heat flux below specified limits. Both the grinding forces and heat flux are obtained from the measured power. Maintaining the monitored power signature from production processes within the acceptable power limits established in this way ensures a “normal” grinding process. Deviations from the normal process signature profile indicate possible process issues. Key Issues of the Work: • Thermal and mechanical constrains of the process • Model fidelity for production use • Adaptive model calibration Status: mainly finished

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Publications of this work: 1. Guo, C., Campomanese, M, McIntosh, G. D., Becze, E. C., and Green, T., 2003,

Optimization of Continuous Dress Creep-Feed Form Grinding Process, Annals of the CIRP, 52/1:259-262.

2. Model-Based Monitoring and Control of Continuous Dress Creep-Feed Form Grinding,” C. Guo, M. Campomanes, D. McIntosh, and C. Becze, Annals of the CIRP, Vol.53, 2004, pp.263-266.

3. Optimization of Continuous Dress Creep-Feed Grinding Using a Model-Based Simulation,” Guo, C., Campomanes, M., Becze, C., Proceedings of the 6th CIRP International Workshop on Modeling of Machining Operations, Hamilton, ON, Canada, May 2003.

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U29 Grinding of Nickel Alloys with Super Abrasive Tools Contact Information: Dr. Changsheng Guo Department of Physical Sciences United Technologies Research Center 411 Silver Lane East Hartford, CT 06108 USA Email: [email protected]:www.utrc.utc.com Abstract: The main objective of the research is to predict the physical parameters such as forces and temperature for grinding nickel alloys of various geometries with both plated and vitrified CBN tools. The CBN grinding process will be investigated with theoretical modeling and simulation with experimental verification. The goal is to develop a simulation based on grinding models that can be readily deployed for various production grinding applications. Key Issues of the Work: • Fundamental grinding models for vitrified and plated CBN models • Transient behavior of the plated CBN grinding Status: On-going Publications of this work: none at the present time.

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U30 Simulation of Single-Grit Grinding and Evaluation of Surface/Subsurface Integrity for Ceramics Based on a CDM Model

Contact: Professor Bi Zhang Dept. of Mechanical Engineering University of Connecticut U-139, 191 Auditorium Rd Storrs, CT 06269-3139 USA. Tel: +1 860 486 2072 Fax: +1 860 486 5088 Email: [email protected] : www.engr.uconn.edu/me/faculty/zhang.html Abstract An abrasive machining process for ceramics is simulated with a nonlinear thermodynamic constitutive model based on the principle of continuum damage mechanics (CDM). The model consists of a set of parallel Maxwell-type elements arranged in series with a spring. It incorporates stochastic material microstructure through two sets of the newly introduced material parameters, spring constants Cr and damping-like coefficients ar (r=1, 2, …, n). Damage is considered cumulative and related with current stress and damage state in a ceramic workpiece during loading, which constitutes damage evolution. A fourth-order isotropic damage tensor is introduced. This highly nonlinear CDM model is reduced to the incremental formulation and approximated by a 3D nonlinear finite element program based on Newton-Raphson method. The stress-strain correlation calculated from the current model is presented for alumina, silicon carbide, and silicon nitride. The predicted results of damage versus the depth of cut for the three ceramics subjected to machining with diamond grit are validated by the experiment. As one example, the development of damage with the movement of the abrasive grit in silicon nitride workpiece is demonstrated by contour plot. The final part of this paper presents the calculated distribution of residual stress in silicon nitride sample and the factors contributing to the distribution are discussed. Key Issues of the Work: Status: Ongoing Publications: 1. Liu, X.B., and Bi Zhang, “Simulation of Single-Grit Grinding and Evaluation of

Surface/Subsurface Integrity for Ceramics Based on a CDM Model,” ASME Journal of Manufacturing Science and Engineering, Vol. 124, (2002) pp. 553-561.

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U31 A Study of Grinding of Nano-structured Ceramic Coatings Contact Information: Professor Bi Zhang Dept. of Mechanical Engineering University of Connecticut U-139, 191 Auditorium Rd Storrs, CT 06269-3139 USA. Tel: +1 860 486 2072 Fax: +1 860 486 5088 Email: [email protected] : www.engr.uconn.edu/me/faculty/zhang.html Abstract This study investigates grinding of nano-structured ceramic coatings and compares grinding of such coatings to that of their conventional counterparts. Two different types of conventional and nano-structured ceramic coatings are ground with cup-type grinding wheels of three different bond types and two different grit sizes. The grinding forces generated and their variations with process parameters such as depth of cut and feedrate are studied. The process parameter effects on the average roughness of the ground coatings are also reported. The normal grinding forces are correlated with the depth of cut and feedrate using a time domain dynamic model, which takes into account the non-linear effects such as cutting stiffness. The study concludes that both simulation and experimental results have a good agreement with each other. This study provides important insights into selecting appropriate grinding parameters for successful grinding of nanostructured materials This study also investigates: • depth profiles of residual stresses using the sin2ψ method combined with grazing incident X-

ray diffraction (GIXD) technique. • formation and propagation of grinding induced lateral crack of nanostructured ceramic

coatings using "indentation fracture mechanics" approach. • damage, mainly surface and subsurface cracks, in ground n-Al2O3/13TiO(2) and n-

WC/12Co coatings. The difference of material properties of these two coatings also influences the subsurface cracks

• Surface textures are measured with stylus profilometry, scanning electronic microscopy (SEM) and atomic force microscopy (AFM), and analyzed using conventional methods and scale-sensitive fractal analysis..

Status: Ongoing Publications: 1. Dey, J., Zhang, B., and Deng, Z. H., “An Experimental Investigation of the Grinding Forces

and Surface Finish on Nanostructured Ceramic Coatings,” Transactions of NAMRI/SME, Vol. 30, (2000) pp. 306-313.

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2. Liu, X.B., and Bi Zhang, “Effects of grinding process on residual stresses in nanostructured ceramic coatings,” Journal of Materials Sciences, Vol. 37, (2002) pp. 3229-3239.

3. Deng ZH, Jin QY, Zhang B, “Critical grinding condition model for predicting grinding induced lateral cracks in nanostructured ceramic coatings,” Key Engineering Materials, Vol. 259 (2004) pp. 273-277.

4. Liu XB, Zhang B, Deng ZH, “Grinding of nanostructured ceramic coatings: surface observations and material removal mechanisms,” International Journal of Machine Tools and Manufacture, Vol. 42 (15) (2002) pp. 1665-1676.

5. Liu, X.B., Bi Zhang, “Grinding of Nanostructural Ceramic Coatings: Damage Evaluation,” International Journal of Machine Tools and Manufacture, Vol. 43, (2003) pp. 161-167

6. Bi Zhang, X.B. Liu, C.A. Brown, and T.S. Bergstrom, “Microgrinding of Nanostructured Material Coatings,” Annals of the CIRP, Vol. 51, (2002) pp. 251-254.

7. Zhang, B., X.B. Liu, Z.H. Deng, and J. Meng, “Grindability Comparison Between Conventional and Nanostructured Material Coatings,” Proceedings of the 5th International Conference on Manufacturing Science, presented in Dalian, China, June 17-19, 2000.

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U32 An Investigation of The Effect of Machine Loop Stiffness on Grinding of Ceramics Contact: Professor Bi Zhang Dept. of Mechanical Engineering University of Connecticut U-139, 191 Auditorium Rd Storrs, CT 06269-3139 USA. Tel: +1 860 486 2072 Fax: +1 860 486 5088 Email: [email protected] : www.engr.uconn.edu/me/faculty/zhang.html Abstract This experimental study deals with the effect of machine structural loop stiffness on grinding of ceramics. The objective of the study is to investigate how the loop stiffness affects grinding forces, wheel actual depth of cut (ADOC) and workpiece strength. A compliant workholder is specifically designed and attached to a precision grinder to simulate grinding machines of various compliances so that the effect of machine loop stiffness can be isolated under otherwise identical conditions. Silicon nitride is used as workpiece material and ground with diamond wheels of two bond types and three grit sizes at machine loop stiffness of four different levels. The ground workpieces are assessed in terms of residual workpiece strength, grinding damage, grinding forces, and ADOC. Theoretical analyses are given to indicate that machine loop stiffness can affect on normal grinding forces and workpiece strength. A discussion is provided to reveal how residual workpiece strength is affected by residual stress and grinding-induced damage. A theoretical model based on mechanics and machine dynamics is also presented to describe the effect of machine stiffness on surface integrity of ground silicon nitride. The modeling and experimental results demonstrate that there exists a critical machine stiffness in grinding of ceramics. When machine stiffness is higher than the critical stiffness, no chatter should occur in the grinding process. In contrast, if machine stiffness is lower than the critical stiffness, chatter can occur in the grinding process that may induce grinding damage. The model can also be used to predict the critical machine stiffness for other types of structural ceramics. 1. Bi Zhang, “An investigation of the effect of machine loop stiffness on grinding of ceramics,”

CIRP Annals-Manufacturing Technology, Vol. 50 (1): (2001) pp. 209-212. 2. Yang FL, Zhang B, Wang JX, Zhu ZQ, Monahan R, “The effect of grinding machine stiffness

on surface integrity of silicon nitride,” J. Manufacturing Science & Engineering-Transactions of the ASME, Vol. 123 (4): (2001) pp. 591-600.

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U33 Grinding-Induced Damage in Ceramics Contact: Professor Bi Zhang Dept. of Mechanical Engineering University of Connecticut U-139, 191 Auditorium Rd Storrs, CT 06269-3139 USA. Tel: +1 860 486 2072 Fax: +1 860 486 5088 Email: [email protected] : www.engr.uconn.edu/me/faculty/zhang.html Abstract Although grinding is widely used as a productive technique for finishing ceramic components in the manufacturing industry, it often causes damage to the machined components. This research studies results on diamond grinding of advanced ceramics, including hot-pressed silicon nitride, hot-pressed alumina, slip-cast zirconia, and pressureless sintered silicon carbide. Grinding induced damage in these ceramics is assessed and characterized using three destructive inspection techniques and progressive lapping technique combined with scanning electron microscopy (SEM), and transmission electron microscopy (TEM). As a result, two types of grinding damage are identified, pulverization and microcracking. Damage depth is found to be related to the properties of ceramic materials, especially their brittleness. For a given grinding condition, damage penetrates deeper in less brittle materials than in more brittle materials. In addition, two types of grinding-induced microcracks are identified, scattered and clustered. The results provide valuable insights into the dependence of grinding-induced damage on the properties of workpiece materials, and on the grit size of grinding wheels. Key Issues of the Work: Status: Ongoing Publications: 1. Bi Zhang, X.L. Zheng, H. Tokura, and M. Yoshikawa, “Grinding induced Damage in

Ceramics,” Journal of Materials Processing Technology, Vol. 132, (2003) pp. 353-364. 2. Zhang B, Yang FL, Wang JX, Zhu ZQ, Monahan R, “Stock removal rate and workpiece

strength in multi-pass grinding of ceramics,” J. Materials Processing Technology, Vol. 104 (3) (2000) pp. 178-184.

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U34 Grinding with Electroplated CBN Wheels Contact Information: Stephen Malkin Distinguished Professor & Head University of Massachusetts Department of Mechanical & Industrial Engineering Engineering Lab Building 160 Governors Drive Amherst, MA 01003-9265, USA Tel: 413-545-0346 Fax: 413-545-1027 Email: [email protected] http: www.ecs.umass.edu/mie/faculty/malkin.html Abstract: This research is concerned with the grinding process for single-layer electroplated CBN grinding wheels. Experiments were conducted to investigate the grinding mechanisms, wheel wear, surface roughness, and temperatures generated in the grinding zone so as to be able to predict the grinding performance and wheel life. The research plan included (1) characterization of the new (unused) wheel topography; (2) experimental measurement and modeling of forces, power, surface roughness, radial wheel wear, and wheel topography during the wheel life; and (3) investigation of the energy partition for calculating grinding temperatures and predicting thermal damage. The wheel was worn down by continuous grinding and temperature measurements were taken at regular intervals. It was found that grinding with an electroplated CBN wheel results in very low grinding temperatures. Low energy partition values were obtained at temperatures below the fluid burnout limit, which was attributed to the high thermal conductivity of the CBN and cooling by the grinding fluid at the grinding zone. Wheel failure occurred by stripping of the abrasive layer when the radial wear reached about 70% – 80% of the grain dimension The workpiece surface generated was found to improve with wheel wear due to the dulling of the abrasive grains. surface roughness throughout the wheel life. Key Issues of the Work: • Measurements of forces, power, temperature, surface quality, and wear for grinding with

single layer electroplated CBN wheels • Wear and life of electroplated CBN wheels • Thermal modeling of the grinding process with electroplated CBN wheel

Status: Near completion 2004. Publications of this work: 1. Z. Shi and S. Malkin, Investigation of Grinding with Electroplated CBN Wheels, Annals of

the CIRP, Vol. 53, 2003, No. 1, pp. 267 – 270. 2. R. P. Upadhyaya and S. Malkin, Thermal Aspects of Grinding with Electroplated CBN Wheels,

ASME Journal of Manufacturing Science and Engineering, Vol. 126, 2004, pp. 117-124.

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3. Z. Shi and S. Malkin, Wear of Electroplated CBN Wheels and the Influence on Grinding Behavior, to be submitted for publication.

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U35 Sensor Integrated “Intelligent” Grinding Wheel Contact Information: Stephen Malkin Distinguished Professor & Head University of Massachusetts Department of Mechanical & Industrial Engineering Engineering Lab Building 160 Governors Drive Amherst, MA 01003-9265, USA Tel: 413-545-0346 Fax: 413-545-1027 Email: [email protected] http: www.ecs.umass.edu/mie/faculty/malkin.html Abstract: A sensor integrated “intelligent” superabrasive grinding wheel was developed for in-process monitoring of the wheel preparation and grinding processes without the need for any instrumentation of the machine tool. The "intelligent" grinding wheel consists of an aluminum core integrated with piezo-ceramic sensors and having superabrasive segments bonded on to the periphery. Multiple sensors embedded near the wheel periphery are used to measure the instantaneous normal force and its variation during each wheel revolution, and additional sensors on the wheel face monitor the accoustic emission. A DSP-based telemetric data acquisition system module attached to the wheel face is used to acquire, process, and transmit data from the rotating wheel to a remote receiver. Key Issues of the Work: • sensor integrated wheel was developed • precludes need for instrumenting the machine tool

Status: Completed 2003. Publications of this work: 1. B. Varghese, S. Pathare, R. Gao, C. Guo, and S. Malkin, Development of a Sensor-Integrated

‘Intelligent’ Grinding Wheel for In-Process Monitoring, Annals of the CIRP, Vol. 50, 2000, No. 1, pp. 231 – 234.

2. B. Varghese, S. Pathare, R. Gao, S. Malkin, and C. Guo, In-Process Monitoring of Truing using a Sensor Integrated Diamond Grinding Wheel, Trans. of NAMRI/SME, Vol. 30, 2002, pp. 295 – 302; presented at NAMRC XXX, West Lafayette, Indiana, May 2002.

3. S. Malkin, R. Gao, C. Guo, B. Varghese, and S. Pathare, Grinding Wheel System, United States Patent Number 6,602,109, issued August 5, 2003.

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U36 Simulation of Continuous Dress Creep Feed Form Grinding Contact Information: Stephen Malkin Distinguished Professor & Head University of Massachusetts Department of Mechanical & Industrial Engineering Engineering Lab Building 160 Governors Drive Amherst, MA 01003-9265, USA Tel: 413-545-0346 Fax: 413-545-1027 Email: [email protected] http: www.ecs.umass.edu/mie/faculty/malkin.html Abstract: A computer simulation program has been developed for simulation and optimization of continuous dress creep-feed form grinding operations. The simulation, which is based upon physical models which ghovern the grinding process, works as a virtual grinder to predict what happens during the process. The simulation is fed by inputs from the user and by an engine which models the technological aspects of the process. Inputs to the process include the workpiece geometry, wheel specification, workpiece material, and the grinding and dressing conditions. Outputs from the process include forces, power, specific energy, wheel consumption, surface roughness, final workpiece profile, grinding temperatures across the profile, cycle time, amd more. As it a practical matter, it can be used to better understand the process, plan grinding cycles, select grinding and dressing parameters, and optimize the cycle Key Issues of the Work: Grinding Simulation Software for Continuous Dress Creep Feed Grinding

• simulates creep feed grind cycles for plain and complex cross-sections • predicts power, forces, temperatures, roughness, wheel consumption

Status: Originally introduced more than 10 years ago, updated versions of the software are currently being applied mainly in the aerospace industry. Publications of this work: 1. N. Chiu and S. Malkin, Computer Simulation for Creep-Feed Form Grinding, Transactions of

NAMRI/SME, Vol. 22, 1994, pp. 119 – 126

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U37 Simulation, Optimization, and Control of Cylindrical Grinding Processes

Contact Information: Stephen Malkin Distinguished Professor & Head University of Massachusetts Department of Mechanical & Industrial Engineering Engineering Lab Building 160 Governors Drive Amherst, MA 01003-9265, USA Tel: 413-545-0346 Fax: 413-545-1027 Email: [email protected] http: www.ecs.umass.edu/mie/faculty/malkin.html Abstract: A software package has been developed to simulate and optimize cylindrical grinding operations. The software contains three main modules: simulation, calibration, and optimization. The simulation module serves as a virtual grinder to predict process behavior and part quality. The calibration learns from actual grinding behavior by modifying model coefficients based on measured parameters such as power, surface roughness, and out-of-roundness. Optimization is used to identify grinding and dressing parameters to minimize or target cycle time based on the calibrated models subject to workpiece quality constraints. The software has also been incorporated into a PC Open Architecture Controller (OAC) as the basis for an Intelligent Grinding System (IGS).

Key Issues of the Work: • Software simulates and optimizes cylindrical grinding cycles • Simulation can be calibrated to actual data • Software is used in bearing and automotive industries.

Status: Originally introduced more than 10 years ago, updated software is being applied today in bearing and automotive industries. Publications of this work: 1. C. Guo and S. Malkin, Cylindrical Grinding Simulation, Optimization, and Control, SME

Paper No. MR01-334, 4th International Machining and Grinding Conf., SME, Troy, Michigan, 2001

2. N. Chiu and S. Malkin, Computer Simulation for Cylindrical Plunge Grinding, Annals of the CIRP, Vol. 42, No. 1, 1993, pp. 383 – 387.

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U38 Minimal Quantity Lubrication (MQL) Grinding using Nanofluid Contact Information: Professor Albert Shih Mechanical Engineering University of Michigan Ann Arbor, MI 48109-2125 Tel: +1-734-647-1766 Email: [email protected] http: me.engin.umich.edu Abstract: This research, sponsored by National Science Foundation and collaborated with University of Massachusetts at Amhest and General Motors, seek to use the nanofluid, a new class of heat transfer and anti-wear fluid, for environmentally benign MQL grinding. Novel fluid delivery systems and workpiece and wheel cooling methods will be explored. Key Issues of the Work: • Grinding fluid delivery, workpiece cooling • New grinding wheels and associate MQL grinding process development Status: Start in 2005 Publications of this work: None

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U39 SiC Wheel for High Material Removal Rate Grinding of Zirconia Contact Information: Professor Albert Shih Mechanical Engineering University of Michigan Ann Arbor, MI 48109-2125 USA Tel: +1-734-647-1766 Email: [email protected] http: me.engin.umich.edu Abstract: This research, sponsored by National Science Foundation and Cummins, investigates the use of low-cost vitreous bond SiC wheel for high material removal rate grinding of zirconia, which is applied for diesel fuel system injector applications. The mechanism of high G-ratio, due to the very low thermal conductivity of zirconia and SiC (relative to diamond), for the conventional abrasive grinding of ceramic is investigated. Key Issues of the Work: • Grinding temperature measurement • Wheel wear and surface integrity analysis Status: Completed in 2004 Publications of this work: 1. J. Shih, A. C. Curry, R. O. Scattergood, T. M. Yonushonis, D. J. Gust, M. B. Grant, S. B.

McSpadden, T. Watkins, 2003, Grinding of Zirconia using the Dense Vitreous Bond Silicon Carbide Wheel, Journal of Manufacturing Science and Engineering, Vol. 125, pp. 297-303.

2. C. Curry, A.J. Shih, R. O. Scattergood, J. Kong, S.B. McSpadden, 2003, Grinding Temperature Measurements in MgO PSZ Using Infrared Spectrometry, J. Am. Ceram. Soc., Vol. 86, pp. 333-341.

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U40 Wire EDM Truing of Metal Bond Diamond Grinding Wheels Contact Information: Professor Albert Shih Mechanical Engineering University of Michigan Ann Arbor, MI 48109-2125 Tel: +1-734-647-1766 Email: [email protected] http: me.engin.umich.edu Abstract: This project, sponsored by US Department of Energy and National Science Foundation, develops the technology to use wire EDM truing of a rotating metal bond diamond grinding wheel. The surface topography and wear mechanism of the diamond wheel after truing and after grinding of ceramics is investigated using the stereo SEM. The EDMed grinding wheel with specific form was applied to grind the ceramic workpiece. Form accuracy and surface roughness of ground ceramic workpiece are studied. Key Issues of the Work: • Wheel wear of the EDM diamond wheel • Workpiece form accuracy and surface roughness Status: Completed in 2003 Publications of this work: 1.

2.

B. K. Rhoney, A. J. Shih, R. O. Scattergood, J. L. Akemon, D. J. Gust, M. B. Grant (2002) “Cylindrical Wire Electrical Discharge Machining of Metal Bond Diamond Wheels for Ceramic Grinding,” International Journal of Machine Tool and Manufacture, Vol. 42, pp. 1355-1362. B. K. Rhoney, A. J. Shih, R. O. Scattergood, R. Ott, S.B. McSpadden (2002) “Wear Mechanism of Metal Bond Diamond Wheels Trued by Wire Electrical Discharge Machining,” Wear, Vol. 252, pp. 644-653.

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U41 Deterministic Grinding and Polishing of Ceramics with Compliant Tools Contact Information: Professor Stephen J. Burns Department of Mechanical Engineering University of Rochester Rochester, NY 14627- 0132, USA Email: [email protected] http: http://www.me.rochester.edu/ Abstract: CNC grinding and polishing of ceramics and glasses for durable optical applications. The purpose is to achieve rapid, high quality finishing of very hard materials. The most recent emphasis has been developing compliant tools and systems for use on extremely hard, tough ceramics. This work is directly related to developing and upgrading to commercially viable processes. Key Issues of the Work: • The removal process and interface between the tool and the workpiece • Dependence of removal and surface damage on material structure and properties • Tool mechanical compliances and performance Status: On-going Publications of this and related work: 1. C. Bouvier, S. Gracewski, S. J. Burns and E. Fess, Development of compliant tools and

processes to polish axisymmetric surfaces, To be presented at Optifab 2005. 2. C. Bouvier, S. Gracewski, S. J. Burns and E. Fess, Prediction of the depth of cut for tools

having a finite contact patch, To be presented at Optifab 2005. 3. S.J. Burns, P.D. Funkenbusch, S. M. Gracewski, J. C. Lambropoulos, and J. Ruckman,

Surface features and residual strains in AlON grinding, Proceedings of the SPIE, 4451 (2001), 165-173.

4. S. J. Burns F. Dahmani, A.W. Schmid, J.C. Lambropoulos and C. Pratt, Nanoindentation technique for measuring residual stress field around a laser-induced crack in fused silica, Journal of Materials Science, 33, 4677 (1998)

5. R. Meehan and S. J. Burns, Mechanics of Cutting and Slitting Webs, Experimental Mechanics, 38, 103 (1998).

6. S. J. Burns R.R. Meehan, J. Kumar, M. Earl and E. Svenson, The Role of Blade Sharpness in Cutting Instabilities of Polyethylene Terephthalate, J. of Materials Science Letters, 18, 93 (1999)

7. S. J. Burns F. Dahmani, A.W. Schmid and J.C. Lambropoulos, Dependence of birefringence and residual stress near laser-induced cracks in fused silica on laser fluence and on laser-pulse number, Applied Optics 37, 7772 (1998)

8. S. J. Burns F. Dahmani, A.W. Schmid, J.C. Lambropoulos and S. Papernov, Arresting ultraviolet-laser damage in fused silica, Optics Letters, 24, 516 (1999)

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U42 Precision Grinding and Polishing of Ceramics and Glasses Contact Information: Professor Paul Funkenbusch Department of Mechanical Engineering University of Rochester Rochester, NY 14627, USA Email: [email protected] http: http://www.me.rochester.edu/ Abstract: CNC grinding and polishing of ceramics and glasses especially to the ultrahigh precision (roughness and form) required for optical applications. The major emphasis in this work is on developing and upgrading commercially viable processes. Key Issues of the Work: • Enhancement of process flexibility and robustness • Dependence of removal and damage on material microstructure and properties • Tool characterization and performance Status: On-going Publications of this work: 1. Yi Li, P. D. Funkenbusch, S. M. Gracewski, and J. Ruckman, Tool Wear and Profile

Development in Contour Grinding of Optical Components, International Journal of 2. Machine Tools and Manufacture, 44 (2004), 427-438 3. Sha Tong, S. M. Gracewski, and P. D. Funkenbusch, Minimizing Chatter in Deterministic

Microgrinding by Process Parameter Selection, Technical Digest of the SPIE, 4. TD02 (2003), 28-30 5. F. H. Mrakovcic, B. Sternberg, J. Shapiro, S. Gracewski, and P. Funkenbusch, Effect Of

Fluid Jet Polishing on Optical Surfaces, Technical Digest of The SPIE, TD02 (2003), 38-40 6. Y. Li, S.M. Gracewski, 7. P.D. Funkenbusch, and J. Ruckman, Analysis of Chatter in Contour Grinding of Optical

Materials, International Journal of Machine Tools and Manufacture, 42 (2002), 1095-1103 8. R. Thonggoom, P.D. Funkenbusch, S. M. Gracewski, and J. Ruckman, Modeling of Tool

Shape Evolution in Conformal (Raster) Grinding, Proceedings of the SPIE, 4451 (2001), 145-152

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U43 Towards an Understanding of Grinding Wear and Lay Patterns Contact Information: Dr. Michael P Hennessey Engineering Department and the Center for Applied Mathematics (CAM) University of Saint Thomas Saint Paul, Minnesota Email: [email protected]://www.stthomas.edu/technology/faculty/Hennesseypage.htm Abstract: Several basic theories applicable to enhancing the understanding of residual wear and lay patterns generated by a rotating circular coated-abrasive disk were researched, specifically the following: • Cumulative swept area wear theory • Oriented swept area theory • Final direction lay pattern theory Corroborating experimental results were presented for the final direction lay pattern theory. The study achieved correspondence between the mathematical model and the experimental data. It is hoped that this work can be used to better understand grinding wear and lay patterns and motivates the further study of work-piece presentation optimization problems, especially for the case of a rotating circular coated-abrasive disk. The work may lead to new kinematic approaches being used for disk rotation, e.g. random orbit. Key Issues of the Work: • Future applied mathematical generalization needed, including associated experimental work • Part presentation optimization problems Status: Ongoing Publications of this work: 1. M. P. Hennessey, S. H. Lin, Understanding Wear and Lay Patterns Generated by a Rotating

Circular Abrasive Disk, Abrasives magazine, Jan/Feb 2004

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U44 Thermal Effects on Subsurface Damage During the Surface Grinding of Titanium Aluminide

Contact: Dr. Wesley L. Stone Assistant Professor Engineering and Technology Department Western Carolina University 226 Belk Building Cullowhee, NC 28723, USA Tel: 828-227-2168 Fax: 828-227-7838 e-mail:[email protected] website:http://et.wcu.edu/ET_FS-stone.htm Abstract: This research focused on the surface grinding of titanium aluminide (TiAl) with an emphasis on subsurface damage and its relationship to workpiece temperatures during grinding. The results from this research fell into six major components: Experimental determination of mechanical and thermophysical properties of TiAl as a function of temperature from room temperature to 800°C Theoretical model of temperature profile during grinding Numerical (Matlab) model of temperature profile during grinding Experimental evaluation of temperatures during grinding (Al2O3, CBN, and Diamond wheels) Theoretical model of depth of subsurface plastic deformation Experimental evaluation of depth of subsurface plastic deformation Key Issues of the Work: Subsurface plastic deformation during surface grinding of TiAl Experimental, numerical, & theoretical evaluation of workpiece temperature during grinding Status: Research completed 2002; dissertation completed 2003; some publications in print (see below), others in process Publications of this work: 1. Stone, W. L., Kurfess, T. R., “Titanium Aluminide Thermal Diffusivity, Heat Capacitance,

and Coefficient of Thermal Expansion as a Function of Temperature,” Transactions of the North American Research Institute, Vol. 30, pp. 417-421, May 2002.

2. Stone, W. L., Kurfess, T. R., "Titanium Aluminide – Material Properties as a Function of Temperature," Proceedings of the Japan - USA Symposium on Flexible Automation, Hiroshima, Japan, Vol. 1, pp. 533-536, July 2002.

3. Stone, W. L., “Thermal Effects on Subsurface Damage During the Surface Grinding of Titanium Aluminide,” Doctoral Dissertation, Georgia Institute of Technology, 2003.

4. Stone, W., Kurfess, T., “Grinding Titanium Aluminide: Subsurface Damage,” Grinding and Abrasives Magazine, Jan/Feb 2004, pp. 22-26.

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U45 Measurement and Analysis of Forces in Diamond Roll Dressing Contact Information: Christopher A. Brown, PhD, PE Professor of Mechanical Engineering Worcester Polytechnic Institute Worcester, Massachusetts, USA Tel: 508 831-5627 Fax:508 831-5673 email: [email protected] http://www.wpi.edu/+mfe/SurfMet Abstract In this work the forces and displacements in diamond roll, plunge dressing are studied over a range of feed rates with the objective of investigating threshold forces. It describes the equipment, instrumentation, and data reduction methods used in the study. Building on previous work (King and Hahn, 1986, Hahn and Lindsay, 1970), this research studies the normalized material removal rates and the normalized normal dressing forces as functions of time. Two regimes appear to exist as functions of feed rates. Each regime can be extrapolated to zero feed and makes a non-zero threshold with the force axis. The force threshold, at feed rates above 3 mm/min is 1.06 N/mm width of grinding wheel and the force threshold, at feed rates below 3 mm/min is 0.12 N/mm width of grinding wheel. Key Issues with this Work: • Getting Bob Hahn’s test machine working again • Establishing the best method of measuring wheel surface Status: Ongoing Publications of this Work: Submitted

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U46 Development of Next Generation Grinding Wheels Contact Information: Dr. Mark Jackson, Professor, Department of Mechanical Engineering Technology Purdue University West Lafayette, IN 47907 USA Email: [email protected] http:www.tech.purdue.edu Abstract: Next generation grinding wheels are in the process of development to aid micro and nanomanufactruing processes. Low specific grinding energy grinding wheels are being constructed using laser assisted and lithographic techniques to produce even structure and open grinding wheels. The development of bonding systems using science-based materials processing is also under way. Key Issues of the Work: • Development of bonding systems • Development of open structured wheels that grind with low specific grinding energy • Micro and nanofabrication of abrasive cutting tools/wheels. Publications of this work: 1. M. J. Jackson, C. J. Davis, M. P. Hitchiner, and B. Mills, High-Speed Grinding with c.B.N.

Grinding Wheels – Applications and Future Developments, Journal of Materials Processing Technology (2001), 110, 78-88. ISSN 0924-0136.

2. M. J. Jackson and B. Mills, Vitrification Heat Treatment and the Dissolution of Quartz in Grinding Wheel Bonding Systems, Journal of the Institute of Materials, Minerals, and Mining - British Ceramic Transactions (2001), 100, 1-8. ISSN 0967-9782.

3. M. J. Jackson, Vitrification Heat Treatment During the Manufacture of Corundum Grinding Wheels, Transactions of S.M.E. – Journal of Manufacturing Processes, (2001), 3, 17-28. ISSN 1526-6125.

4. M. J. Jackson, N. Barlow, and K. K. B. Hon, Computer Aided Design of High-Performance Grinding Tools, Proceedings of the Institution of Mechanical Engineers (London), Part B - Journal of Engineering Manufacture, (2001), 215, 583-588. ISSN 0954-4054.

5. M. J. Jackson, R. T. Wakefield, S. A. Jones, B. Mills, and W. B. Rowe, Materials Selection Applied To Vitrified Corundum Grinding Wheels, Journal of the Institute of Materials, Minerals, and Mining – British Ceramic Transactions, (2001), 100, 229-236. ISSN 0967-9782.

6. M. J. Jackson and B. Mills, Microscale Wear of Vitrified Abrasive Materials, Journal of Materials Science (2004), 39, 2131-2143. ISSN 0022-2461.

7. M. J. Jackson, Fracture Dominated Wear of Sharp Abrasive Grains and Grinding Wheels, Proceedings of the Institution of Mechanical Engineers (London): Part J – Journal of Engineering Tribology (2004), 218, 225-235, ISSN 1350-6501.

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U47 HELID (High-speed Electrolytic In-process Dressing) - An Efficient Method for In- process Dressing of High-speed Grinding Wheels Contact Information: Professor Zhenqi Zhu Associate Professor Stevens Institute of Technology Hoboken, NJ 07030, USA Tel: 201-216-5582 Fax: 201-216-8315 Email: [email protected] Abstract: An innovative method, namely, HELID (High-speed Electrolytic In-process Dressing) is developed. The HELID method is based on a foil electrode and the hydrodynamic interaction between the high-speed wheel surface and the foil. An important indicator of the effectiveness of electrolytic in-process dressing is the initial dressing current. For an electrode of a certain length and width wrapping around a grinding wheel, given the same wheel surface condition, the initial dressing current for the conventional ELID method featuring a solid electrode, decreases with a wheel surface speed of 30 m/s. While for the HELID method featuring foil electrode, the initial dressing current is kept at the same level. The ratio of initial dressing currents between HELID and ELID is between 5 to 7 given a range of input voltage and current - a factor of 5-7 times in dressing efficiency at a low speed of 30 m/s. Key Issues of the Work: • To gain fundamental understanding of the fluid dynamics involved in the high-speed flow of

the electrolyte and develop strategies for the control of electrolyte flow; • To initiate the HELID grinding technique based on innovative electrolyte delivery methods; • To gain knowledge on HELID process though modeling, simulation and experiment; • To realize cost-effective HELID grinding to achieve nanoprecision and high material

removal rate. Status: Completed 2004 Publications of this work: 1. Z. Zhu, “Technological Progress of Supperabrasive Dressing,” Abrasive Magazine, June,

2002, pp.18-21. 2. Z. Zhu and X. Liu, “Method and Device for High Speed Electrolytic In-Process Dressing for

Ultra-Precision Grinding,” U.S. Patent No. 6,547,648, April 15, 2003. 3. Z. Zhu, X. Liu,, and S. Thangam, “Study Of Foil Electrode For High Speed Electrolytic In-

Process Wheel Dressing,” Machining Science and Technology, vol. 7, n1, pp.65-81, 2003. 4. Z. Zhu, X. Wang, and S. Thangam, “Simulation and Analysis of Rigid/Foil Electrolytic In-

Process Dressing (ELID) Systems for Grinding,” ASME J. of Manufacturing Science and Technology, vol. 126, n3, pp.565-570, 2004.

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U48 Thermal Aspects of Grinding and Characteristics of Ground Surfaces Contact Information: Professors Srinivasan Chandrasekar and Thomas N. Farris Center for Materials Processing and Tribology College of Engineering Purdue University West Lafafyette, IN 47907-1287 Email: [email protected], [email protected] http://roger.ecn.purdue.edu/~tribmat/ Abstract: Thermals phenomena associated with the grinding process are being studied experimentally and analytically. The experimental investigation involves measurement of grinding temperature using full-field, infra-red radiation measurement techniques; and development and use of methods for analyzing mechanical characteristics and microstructure of ground surfaces at the micrometer and sub-micrometer length scales. Based on these measurements, different forms of thermally induced changes on ground surfaces have been identified together with their mechanical signatures. A thermal model has been developed to estimate energy partition and temperature distributions of wheel and workpiece. Correlations between thermally induced-changes, temperature and metallurgical parameters on workpiece are being developed to enable control of ground surface characteristics. Key Issues of the Work: • Measurement of workpiece and grain temperature at high resolution • Characterization of ground surface parameters such as micro- and nano-hardness, residual

stress distribution and microstructure • Modelling to establish correlation between ground surface characteristics and input

parameters. Status: On-going Journal Publications related to this work (last 8 years): 1. S. A. Hucker, J. B. Mann, T. N. Farris and S. Chandrasekar. Thermals aspects of grinding

with superabrasives, parts 1 and 2. Abrasives, 29-6 (1996) and 30-1(1997). 2. J. B. Mann, T. N. Farris, and S. Chandrasekar. A model for grinding burn. SAE Transactions,

paper no. 972247, 1997. 3. Y. Ju, T. N. Farris, and S. Chandrasekar. Theoretical analysis of heat partition and

temperatures in grinding. Journal of Tribology, 120-4, 1998, 789-94. 4. S. P. Moylan, S. Kompella, S. Chandrasekar and T. N. Farris. A nano-indentation study of

thin surface layers affected by manufacturing processes. Proc. Leeds-Lyon Symp. Trib., 28, 2001, 895-903.

5. S. Kompella, S. Chandrasekar, and T. N. Farris. Techniques for characterization of grinding wheel-workpiece combinations, Proc. I.Mech. Engrs., Series B, 125, 2001, 1385-95.

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6. S. Kompella, S. P. Moylan, and S. Chandrasekar. Mechanical properties of thin surface layers affected by material removal processes. Surface and Coatings Technology, 146-147, 2001, 384-90.

7. S. Akcan, S. Shah, S. P. Moylan, P. N. Chhabra, S. Chandrasekar and H.T. Yang. Formation of white layers in steels by machining and their characteristics. Metallurg. Matls. Trans., 33A, 2002, 1245-1254.

8. J. Hwang, S. Kompella, S. Chandrasekar and T. N. Farris. Measurement of temperature field in surface grinding using infra-red imaging system. Jour. Trib., 125-2, 2003, 377-83.

9. S. P. Moylan, S. Kompella, S. Chandrasekar and T. N. Farris. A new approach for studying mechanical properties of thin surface layers affected by manufacturing processes. J. Mfg. Sci. Engg, 125-2, 2003, 310-315.

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U49 Mechanics of Polishing and Superfinishing Contact Information: Professors Srinivasan Chandrasekar and Thomas N. Farris Center for Materials Processing and Tribology College of Engineering Purdue University West Lafayette, IN 47907-1287 Email: [email protected], [email protected] http://roger.ecn.purdue.edu/~tribmat/ Abstract: Contact mechanics of abrasive polishing and superfinishing processes is being studied. A key aspect of the study is the relation between particle size (or stone topography and particle size) distribution, and material removal rate and surface finish evolution during the finishing. It has been shown using contact mechanics model and experiment that very few particles are actually involved in the cutting process in polishing and this is a consequence of the relatively broad particle size distribution. Methods have also been developed to measure polishing/ superfinishing forces. The evolution of surface finish has been simulated. Key Issues of the Work: • Role of particle size distribution • Contact mechanics modeling • Forces and surface finish. Status: Polishing study ongoing. Superfinishing study completed. Journal publications related to this work (last 8 years): 1. V. H. Bulsara, Y. Ahn, S. Chandrasekar and T. N. Farris. Polishing and lapping temperatures.

Jour. Trib., 119-1, 1997, 163-70. 2. S. H. Chang, S. Balasubramahnya, S. Chandrasekar, T. N. Farris and F. Hashimoto. Forces

and specific energy in superfinishing of hardened steel. CIRP Annals, 46-1, 1997, 257-60. 3. S. Chandrasekar and T. N. Farris. Machining and surface finishing of brittle solids. Sadhana,

Proc. Ind. Acad. Sci., 22-3, 1997, 473-81. 4. V. H. Bulsara, S. Chandrasekar and T. N. Farris. Mechanics of polishing. Jour. Appl. Mech.,

65-2, 1998, 410-416. 5. S. H. Chang, T. N. Farris, and S. Chandrasekar. Contact mechanics of superfinishing. Jour.

Trib., 122-1, 2000, 388-93. 6. S. H. Chang, T. N. Farris, and S. Chandrasekar. Experimental study of superfinishing. Proc.

Inst. Mech. Engrs. Series B, 217, 2003, 941-51.

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U50 Double Side Grinding of Advanced Ceramics with Diamond Wheels Contact Information: Professor Ioan D. Marinescu Precision Micro-Machining Center College of Engineering University of Toledo Ohio, USA Tel: +1 419 530 8226 Fax: 419 530 8206 Email: [email protected] Abstract A double-side grinding computerized kinematical model accounting for piece rotation inside the carrier slot was developed. Simulated trajectories for random points located on the end faces of the workpiece, both in a global fixed coordinate system and in each wheel's rotating coordinate system, were predicted. Experiments for different kinematical and coolant conditions were carried out. A strong correlation was found between the predicted length of trajectory for a point on the piece surface and the experimental material removal rate. Conclusions on optimized double side grinding process for advanced ceramics with fine diamond were drawn. Status: Ongoing Publications of this Work: Marinescu, I. D.,C.E. Spanu, M.P. Hitchiner, M. Hoff, A. Nelson, Double Side Grinding of Advanced Ceramics with Diamond Wheels, CIRP STC-G, Paris, 2005

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U51 Dry Versus Wet Grinding With Superabrasives Contact Information: Professor Ioan D. Marinescu Precision Micro-Machining Center College of Engineering University of Toledo Ohio, USA Tel: +1 419 530 8226 Fax: 419 530 8206 Email: [email protected] Abstract In abrasive processes, the use of fluids has two main objectives: cooling, and lubrication of the workpiece/tool pair. The literature points out that the lubricating function of the fluid is more important than the cooling one. Thus, it appears inadequate to name the grinding fluids "coolants" or "cooling fluids". Modern grinding fluids, obtained as a result of tribological research of complex chemica1 formulas, have technological properties which favor the micro-cutting process: high pressure resistance, reduced wear and corrosion, and are also more environmentally safe. In brief, the definition for these fluids can be: fluids used during the abrasive process in order to lubricate the pair abrasive tool/workpiece; remove the microchips from the work area; and reduce the temperature. It is also important to know that using grinding fluids can very little influence the specific costs (about 5%). The dry abrasive processes produce high intensity wear of the tool materials and over-heat the work-piece. which may have as a result structural (phase) transformations of the workpiece material- When “wet grinding” is performed- the abrasive tool/workpiece friction pair will work in a mixed regime, during which the tribo-chemical processes are very intense. In this case it is very difficult to elucidate the nature of the abrasive processes because of the complex contact of the solid surfaces of the friction pair. This paper presents a study on the influence of the grinding fluids on two specific pairs for tool grinding: diamond grinding wheel/sintered metal carbide sample; and CBN grinding wheel / high speed steel sample. Status: ongoing Publications of this Work: 1. Grigorescu, A., Marinescu, I.D., Zaneli, G., Optimization of Dry Tool and Cutter Grinding

Using ABN360, Industrial Diamond Journal, nr.3/1982.

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U52 Surface Generation in the Case of Honing with Superabrasives Contact Information: Professor Ioan D. Marinescu Precision Micro-Machining Center College of Engineering University of Toledo Ohio, USA Tel: +1 419 530 8226 Fax: 419 530 8206 Email: [email protected] Abstract The honing process is well known as a finishing process in order to improve the form accuracy, as well as the surface roughness. In most cases, the surface roughness is a function not only of the grit size of the superabrasive, but also of the shape of tile superabrasive grains- This paper presents a kinematics study of the honing process, taking into consideration the combination of the honing motion and the shape of the superabrasive grains. These kinematics equations were developed in order to serve as the basis for tribo-technological modeling of this process.

Status: ongoing Publications of this Work: 1. Bardac, D., and Marinescu, I., Surface Generation in the Case of Honing with

Superabrasives, Proc. of the 3rd International Machining & Grinding October 4-7, 1999 Cincinnati, Ohio

2. Marinescu, I.D., Fine Honing & Superfinishing with Superabrasives, Proceedings of SME International Honing and Micro-Finishing Conference, Romulus, MI, USA, April 28-29, 1999.

3. Ohmori, H., Marinescu, I.D., ELID Honing of Ceramic Materials, Proceedings of SME International Clinic on Honing, Cleveland OH, USA, October 20, 1999.

4. Matsumori, N., Akashi, K., Ikawa, N., Marinescu, I.D., Advanced Super-finishing and Honing by Fine Superabrasive Stone, Superabrasives & CVD Diamond, Omni press, 1998, pp.103-127.

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U53 Laser Assisted Grinding of Ceramics Contact Information: Professor Ioan D. Marinescu Precision Micro-Machining Center College of Engineering University of Toledo Ohio, USA Tel: +1 419 530 8226 Fax: 419 530 8206 Email: [email protected] Abstract High-performance lasers can be successfully used to assist in the process of grinding brittle materials. In this process the workpiece area is heated directly before the grinding wheel, thus reducing the temperature gradient as well as the surface and subsurface damage. This method permits high stock removal rates and increases the productivity and efficiency of this process. The work deals with the fundamentals of this method and presents a number of results of laser-assisted grinding of four types of ceramics: alumina, silicon nitride, zirconia and ferrite. A laser was mounted on a surface grinder in order to preheat the ceramic surface just before it contacts the grinding wheel. The aim of the experiment was to show that it is possible to increase the ductility of ceramics through a pre-heating process and to increase the depth of cut while the material is in the ductile state. Status: completed Publications of this Work: 1. Marinescu, I. D., Laser Assisted Grinding of Ceramics, Interceram Int. Ceramic Journal, Vol.

47, No. 5, 1998, pp. 314-320 2. Marinescu, I.D., C02 Laser Assisted Grinding of Ceramics, 2nd International Conference on

Machining of Advanced Materials (MAM) VDI, Aachen, Germany, October 1996. 3. Marinescu, I.D., Laser Assisted Grinding of Ceramics, Proceedings of the SUPERGRIND

'95, Storrs, CT, November 2-3, 1995, pp. 183-189. 4. Marinescu, I.D., Laser Assisted Grinding of Ceramics, Grinding & Machining of Advanced

Materials Conference, Pittsburgh, PA, October 11-13, 1995.

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U54 Investigation of Material Removal Mode in Ceramic Grinding Contact Information: Professor Ioan D. Marinescu Precision Micro-Machining Center College of Engineering University of Toledo Ohio, USA Tel: +1 419 530 8226 Fax: 419 530 8206 Email: [email protected] Abstract A material removal mode in ceramics grinding has been developed based on single-point diamond abrasive grinding experiments and analytical investigation. Surface cracks, micro-plastic deformation and re-crystallization occurring in ceramics grinding have been studied. The mode has been described as three regions: brittle fracture; non-elastic deformation; and residual damages. The process of grinding ceramics experiences elastic and finitely micro-plastic deformation, crack initiation and propagation, and chip formation. Status: Completed Publications of this Work: Ling Y., I. Marinescu, T. Matsuo, R. Chen, Investigation of Material Removal Mode in Ceramic Grinding, CIRP STC-G Presentation, Paris, 2001.

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U55 CBN - Performance Superfinishing for Toroidal Surfaces Contact Information: Professor Ioan D. Marinescu Precision Micro-Machining Center College of Engineering University of Toledo Ohio, USA Tel: +1 419 530 8226 Fax: 419 530 8206 Email: [email protected] Abstract Superfinishing is applied as a final operation after fine grinding. The process is used in order to improve the surface finish and the workpiece geometrical precision. Usually it comprises of two stages: rough superfinishing, using higher stock removal for geometrical corrections and fine superfinishing, which is concerned mainly with the surface roughness. The paper presents a comparative study on the performances of the abrasives stones used in the process. CBN stones were compared against the most used conventional abrasives, silicon carbide (SiC) and aluminum oxide (Al2O3) and against diamond by examining the some of the most important cut parameters (stock removal rate, superfinishing ratio, surface finish). The study focuses on the superfinishing of toroidal surfaces (the samples used during the experiments were inner ball bearing rings) where the first stage of the process is very important due to the use of form tools in the previous process (in our case form grinding wheels for fine grinding). For this stage we found that CBN outperforms both conventional superabrasives and diamond. It has been also observed that the abrasive type influences the correlation between the process parameters and the output values. Status: ongoing Publications of this Work: 1. Dontu, G., Cioc, S., Neagu-Ventzel, S., Marinescu, I.D., Olson, W., Qualitative Analysis of

the Wear of Stone and Ring in Superfinishing Bearing Rings, Using FEM, Transactions of the NAMRI, of SME and NAMRC, Gaithersburg, FL, May 24-27, 2001.

2. Marinescu, I.D., Dontu, G., Bordeianu, E., High Efficiency Super-finishing of Bearing Rings with CBN, NMRC XXVI, Georgia Institute of Technology, Atlanta, GA, May 19-22, 1998, pp.27-33

3. Marinescu, I.D., Bordeianu, E., Superabrasive Versus Conventional Abrasives in Superfinishing, Journal of Engineering for Industry, 1996.

4. Dontu, G., Neagu-Ventzel, S., Marinescu, I., Johnson, P., Study of Track/CBN Abrasive Stone Contact in Superfinishing of Ball Bearing Rings, International Technical Conference on Diamond, Cubic Boron Nitride and their Applications, Vancouver, Canada, Vancouver, July 17-20, 2000.

5. Marinescu, I.D., Fine Honing & Superfinishing with Superabrasives, Proceedings of SME International Honing and Micro-Finishing Conference, Romulus, MI, USA, April 28-29, 1999.

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U56 Development of a Comprehensive Robotic Grinding Process Contact Information: Dr. Yunquan Sun [email protected] Abstract : While robotic manipulators are extensively used in grinding industry, they are limited to applications, which generally feature lower accuracy requirements, simpler geometries and lower rates of material removal. The main barrier in extending robot’s utilization in grinding applications beyond the mentioned limitations is the process control stability due to lower system mechanical stiffness and higher mechanical compliance. In this research, we have developed a comprehensive system (hardware, software, process model) that achieves a high degree of accuracy and material removal rate in parts with complex geometries. Our development presents a significant advance in the state-of-the-arts in robotic grinding. The novelty of this research is in the process design, control, calibration and stability rather than the mechanics of grinding. In our experimentations, this comprehensive process has been applied to turbine blade grinding. The high quality of the surface finish as well as the total process time, demonstrate the effectiveness of the method as well as its potential for future widespread applications of the robotic grinding. Status: Ongoing Publications of this Work: 1. Sun, Y., Development of a Comprehensive Robotic Grinding Process, University of

Connecticut, Department of Mechanical Engineering, 2003 PhD thesis 2. Lindqvist, A., Gan, Z., and Sun, Y., Interactive Program Generation for Air Foil Finishing

with Blue Intelligence, Proceedings of the 32nd ISR (International Symposium on Robotics), 19-21 April 2001

3. Bone, G., M. Elbestawi, R. Lingarkar, and L. Liu, "Force Control in Robotic Deburring", Journal of Dynamic System, Measurement, and Control, Transactions of the ASME, Vol. 113, Sept. 1991, pp395-400

4. Her, M. and H. Kazerooni, "Automated Robotic Deburring of Parts Using Compliance Control", Journal of Dynamic System, Measurement, and Control, Transactions of the ASME, Vol. 113, March 1991, pp60-66

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U57 Development of Freeform Grinding Methods for Drills Contact Information: Professor Jun Ni Director, SM Wu Manufacturing Research Center College of Engineering, University of Michigan 1023 H. H. Dow Bldg, 2350 Hayward St. Ann Arbor, MI 48109 USA Phone: 734-936-2918 Fax: 734-936-0363 Email: [email protected] Abstract: A manufacturing issue in drill point grinding was handled in this study, which was the generation of the desired normal rake and relief angle distributions. Freeform grinding methods were developed that used the standard wheel edge or face. Mathematical representations were made of normal rake and relief angles in terms of the drill geometric parameters. With the developed freeform grinding methods, drills with convex and concave flank surfaces could be generated. This study has presented two grinding methods (the wheel−edge and wheel−face grinding methods) to generate the cutting edge profile and the parallel relief surfaces that could meet desired γn and αf distributions. These methods and associated work led to the following findings. • A cutting edge profile could be designed to obtain the desired γn distribution through a few

iterations as described in Appendix 2, which was an indirect method but it provided an accurate correlation between the cutting edge profile and the γn distribution.

• The primary αf distribution could be specified independently of the γn distribution. • The coordinates and the normal vectors of secondary grinding paths were determined by

introducing an offset distance and angle, and the associated coordinate transformations. • The kinematic motions of a 5−axis CNC grinder were identified to suit both the wheel−edge

and wheel−face grinding methods. • The wheel−edge grinding method was successfully applied to generating concave flank

surfaces and freeform convex flanks, but it could retain the possible disadvantages such as unsatisfactory surface finish and integrity due to the nature of sharp edge contact.

Status: Ongoing Publications of this work: 1. Jung, J., R. Major, and Ni, J., Dev. of Freeform Grinding Methods for Complex Drill Flank

Surfaces and Cutting Edge Contours, Int. J. of Mach Tools and Manuf., Vol. 45/1, 2005 2. Ni, J., 1999, “Analyses of Drill Flute and Cutting Angles,” International Journal of Advanced

Manufacturing Technology, Vol. 15, pp. 546−553 3. Lin, X., Ni, J., 1996, “Drill Point Grinding on a Multi−axis CNC Tool Grinder,” Proceedings

of the International Workshop on Automotive Manufacturing Science and Technology, Shanghai Scientific and Technological Literature Publishing House.

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U58 Neural Network Detection of Grinding Burn from Acoustic Emission Contact Information: Professor Peter Willett Information & Computing Systems Group Electrical and Systems Engineering Department U-157, University of Connecticut, Storrs CT, 06268-2157 USA Tel: +1 860 486 2195 Fax: +1 860 486 5585 Email: [email protected] Abstract: An artificial neural network (ANN) approach is proposed for the detection of workpiece "burn", the undesirable change in metallurgical properties of the material produced by overly aggressive or otherwise inappropriate grinding. The grinding acoustic emission (AE) signals for 52100 bearing steel were collected and digested to extract feature vectors that appear to be suitable for ANN processing. Two feature vectors are represented: one concerning band power, kurtosis and skew; and the other autoregressive (AR) coefficients. The result (burn or no-burn) of the signals was identified on the basis of hardness and profile tests after grinding. The trained neural network works remarkably well for burn detection. Other signal-processing approaches are also discussed, and among them the constant false-alarm rate (CFAR) power law and the mean-value deviance (MVD) prove useful. Key Issues of the Work: • High speed data collection Status: Completed Publications of this work: 1. Z. Wang, P. Willett, P. R. DeAguiar, and J. Webster, Neural Network Detection of Grinding

Burn from Acoustic Emission, International Journal of Machine Tools & Manufacture 41 (2001) 283-309

2. Aguiar, P. R., Willett, P., Webster, J. and Z. Wang, “Workpiece Burn Detection During Grinding by Acoustic Emission”, COBEM, Sao Paulo, Brazil, November 1999.

3. Wang, Z., Willett, P., Aguiar, P. R., and J. Webster, “Wheel-Workpiece Contact Detection During Grinding Process by Acoustic Emission Signal”, COBEM, Sao Paulo, Brazil, November 1999.

4. P. de Aguiar, J. Webster, and P. Willett, “Acoustic Emission Applied to Detect Workpiece Burn During Grinding”, to appear in the Proceedings of the International Symposium on Acoustic Emission, Fort Lauderdale FL, January 1998.

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