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Faculty of Manufacturing Engineering
FABRICATION AND CHARACTERISTIC STUDY OF ALUMINA
TOOL USING COLD ISOSTATIC PRESS
Abdul Aziz Bin Adam
Master of Manufacturing Engineering (Industrial Engineering)
2014
© Universiti Teknikal Malaysia Melaka
FABRICATION AND CHARACTERISTIC STUDY OF ALUMINA
TOOL USING COLD ISOSTATIC PRESS
ABDUL AZIZ BIN ADAM
A thesis submitted in fulfillment of the requirements for the degree of Master of Manufacturing
Engineering in Industrial Engineering
Faculty of Manufacturing Engineering
UNIVERSITI TEKNIKAL MALAYSIA MELAKA
2014
© Universiti Teknikal Malaysia Melaka
DECLARATION
I declare that this thesis entitled "Fabrication and Characteristic Study of alumina Tool
Using Cold Isostatic Press" is the result of my own research except as cited in the
references. The thesis has not been accept for any degree and is not concurrently submitted
in candidature of any other degree.
Signature
Name
Date
Abdul Aziz Bin Adam
25th August 2014
© Universiti Teknikal Malaysia Melaka
APPROVAL
I hereby declare that I have read this report and in my opinion this thesis is sufficient in
terms of scope and quality for the award of Master of Manufacturing Engineering
(Industrial Engineering).
Signature
Supervisior Name
Date
. ............ ... r. ...... ..... ........ . Dr. Mohd Sanusi Bin Abdul Aziz
<f'/9 / lol't
DR. MOHD SANUSI llN AIDUl AZIZ Swtior Lectww
Faculty of Manufacturin9 Engineering Universitf Teknlli•I •lcsyli• M.iali•
Hant Tueh Jay• 76100 Durian r.,,....,, MAia•
© Universiti Teknikal Malaysia Melaka
DEDICATION
This thesis is dedicated to my beloved mother, father, siblings and friends. They have been
a source of motivation and strength during moments of despair and discouragement,
support has been shown in incredible ways recently.
© Universiti Teknikal Malaysia Melaka
ABSTRACT
In manufacturing, machining is widely used in the production. The selection of a suitable tool will boost production performance and reduce costs. In this study, alumina cutting tools are fabricated and its characteristics information gained through various experiments. Numbers of previous studies using alumina -based composite cutting tool were done and mostly agreed that the alumina based have the potential to produce a homogeneous ceramic cutting inserts with high performance. However, less research were found for the production of alumina milling cutting insert . Therefore, this study focuses on the application of cold isostatic press to produce alumina cutting insert that has a good microstructure and mechanical properties. The characteristic of cutting insert that has been produced then tested through various experiments and test. The inserts produce accordance to triangle shaped inserts. Alumina powder with purity of 91.4 % was used to produce the cutting tool. The powder then compressed through cold isostatic pressure techniques. The pressure applied is range of 15,000 psi, 20,000psi and 25 ,000 psi. Green body and then dried and sintered at two different temperatures of and 1400 °C and 1550 °C. The density, hardness and shrinkage of alumina milling insert then were studied. Matrix design method was utilized to build experimental and accurate data. Product which were pressed at 20,000 psi and sintered at 1550 °C shows assured result and shall be tested to identify the cutting performance of the inserts.
© Universiti Teknikal Malaysia Melaka
ABSTRAK
Dalam industri pembuatan, pemesinan digunakan secara meluas dalam pengeluaran produk. Pemilihan mata a/at yang sesuai akan membantu memoptimasikan prestasi pengeluaran serta mengurangkan kos. Dalam kajian ini, perkakas pemotong alumina difabrikasi dan sifat-sifat pemotong alumina diuji melalui ujikaji bagi mendapatkan maklumat prestasi sifat perkakas. Beberapa kajian terdahulu menggunakan komposit berasaskan alumina mendapati bahawa perkakas pemotong tersebut berpotensi menghasilkan komponen seramik yang homogen serta berprestasi tinggi. Namun, kurang kajian bagi penghasilan perkakas pemotong kisar alumina. Oleh itu, kajian ini lebih tertumpu kepada aplikasi tekanan sejuk bagi menghasilkan perkakas pemotong alumina yang mempunyai mikrostruktur dan sifat mekanik yang baik. Perkakas yang dihasilkan kemudiannya diuji melalui pelbagai ujikaji bagi mendapatkan maklumat karakter struktur dan mekanikal perkakas. Fabrikasi pembuatan akan mengikut standard komersial TKPN berbentuk segitiga. Fabrikasi perkakas pemotong bermula dengan mendapatkan serbuk alumina ketulenan 91.4%. lni diikuti dengan pembentukanjasad anum perkakas pemotong alumina melalui teknik tekanan sejuk. Tekanan yang dikenakan adalah pelbagai iaitu 15, 000 psi, 20, OOOpsi dan 25, 000 psi. Seterusnya, sampel disinter pada dua suhu yang berbeza iaitu 1400 °C dan 1550 °C. Jasad kemudian dikaji ketumpatan, kekerasan-vikers dan pengecutan Kaedah rekabentuk matrik telah digunakan sepenuhnya untuk membina ujikaji serta data-data yang tepat. Produk yang ditekan di 20, 000 psi dan disinter pada 1550 ° C menunjukkan hasil terjamin dan wajar diuji untuk mengenal pasti prestasi pemotongan serta kualiti pemotongan menggunakan .
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ACKNOWLEDGEMENT
Alhamdulillah, all praises to Allah for the strengths and His blessing in completing this report. I would like to take this opportunity to express my sincere acknowledgement to my supervisor, Dr Mohd Sanusi Bin Abd Aziz from the Faculty of Manufacturing Engineering Universiti Teknikal Malaysia Melaka (UTeM) for his essential supervision and constant support and encouragement toward completion of this report. Not forget special thanks to Dr Raja Izamshah Bin Raja Abdullah for his invaluable help of constructive comments and suggestions. I would also like to express greatest gratitude to Majlis Amanah Rakyat (MARA) for the opportunity and support that been given. Special thanks my beloved parents; siblings and peers for their moral support in completing this report. Lastly, thank you to everyone that have been to crucial participate directly and indirectly in realization this project.
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TABLE OF CONTENT
ABSTRACT ABSTRAK ACKNOWLEDGEMENT TABLE OF CONTENT LIST OF TABLES LIST OF FIGURES LIST OF APPENDICES
CHAPTER 1. INTRODUCTION
1.0 Background Study 1.1 Statement of Purpose 1.2 Problem Statement 1.3 Objectives 1.4 Scope
2. LITERATURE REVIEW 2.0 Introduction
2.1 Ceramic Material 2.1.1 Properties of Ceramic 2.1.2 Properties of Alumina
2.2 Cold Isostatic Press 2.2.1 Types of Cold Isostatic Press 2.2.2 Cold Isostatic Processing 2.2.3 The Pressure Chamber
2.3 Rubber Mould 2.4 CIP Process on Alumina Oxide (Ah03) Powder 2.5 Sintering 2.6 High Speed Milling 2.7 Ceramic Milling Inserts 2.8 Silicon Nitride as Cutting Tool Material 2.9 Previous Study
3. RESEARCH METHODOLOGY 3.0 Introduction 3.1 Project Methodology 3.2 Experimental Matrix 3.3 Sample Preparation
3.3.1 Alumina Powder 3.3.2 Dry Pre-Press By Uniaxial Press Machine 3.3.3 Cold Isostatic Press 3.3.4 Furnace 3.3.5 X-Ray Fluorescence
IV
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PAGE
11
iii iv VI
vii x
1 2 2 3 3
4 6 6 7 9 10 11 12
14 15 16 18 19 22 24
26 28 28 30 32 32 34 35 38
4.
5.
6.
3.4 Responce Measurement 3.4. l Hardness Measurement 3.4.2 Density Measurement and Water Absorption 3.4.3 Linear Shrinkage 3.4.4 Thermal Expansion 3.4.5 Flexural Test I Modulus of Rupture 3.4.6 Fracture I Charpy Impact Test
RESULT 4. l Introduction 4.2 The Element Composition Analysis 4.3 Green Density (Before Sintering) 4.4 Density After Sintering 4.5 Water Absorption 4.6 Shrinkage (Green Compact) 4. 7 Shrinkage After Sintered 4.8 Thermal Expansion 4.9 Hardness 4.10 Flexural Strength (Modulus of Rapture) and Flexural Modulus
4.10.1 Flexural Strength 4.10.2 Flexural Modulus
4.11 Impact Test
DISCUSSION 5.1 Mechanical analysis
5.1.1 Green Density 5.1.2 Sintered Density 5.1.3 Water Absorption 5.1.5 Shrinkage 5. l . 6 Hardness 5.1. 7 Flexural Strength
CONCLUSIONS AND RECOMMENDATIONS 6.1 Conclusion
REFERENCES
APPENDICES
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38 38 39 41 41 43 44
46 47 49 50 55 59 60 63 64 68 68 69 69
71 71 72 72 73 74 75
76
78
82
TABLE
2.1
2.2
2.3
2.4
2.5
2.6
2.7
3.1
3.2
3.3
3.4
3.5
3.6
4.1
LIST OF TABLES
TITLE
Properties of various ceramic at room temperature
General properties of alumina powder
Properties of polyurethane
Operating pressure guidelines for various powder
Common inserts shape codes
Typical inserts tolerances
Common inserts hole configuration
Selected process parameters and number of levels
Pressing pressure 15 Kpsi with sintering temperature
Pressing pressure 20 Kpsi with sintering temperature
Pressing pressure 25 Kpsi with sintering temperature
Detailed specification of cold isostatic press machine
Firing Program
Analyse Concentration Table of Alumina TM-DAR using XRF
PAGE
7
9
15
16
21
22
22
29
29
29
30
34
37
48
4.2 The comparison between experimental and theoretical alumina density 53
4.3 Percentage water absorption of alumina powder sintered at l 400°C 56
4.4 Percentage water absorption of alumina powder sintered at 1550°C 57
4.5 Outcomes of impact test 70
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LIST OF FIGURES
FIGURE TITLE PAGE
2.1 Arrangements of ions of 0 2· A13
+ inside Ah03 8
2.2 Micrograph of alumina powder 8
2.3(a) Schemetic diagram of dry bag CIP 10
2.3(b) Schemetic diagram of wet bag CIP 10
2.4 Process of wet bag cold isostatic pressing 11
2.5 Process of wet bag dry isostatic pressing 12
2.6 Full threaded cover 13
2.7 Breech lock pressure chamber type 13
2.8 Pin Closure ASME type 14
2.9 Rubber mould sample 15
2.10 Sintering mechanisme on particle densification 17
2.11 Types of milling process 19
2.12 Standard nomenclature mill cutting inserts configuration 20
3.1 Process Flow 27
3.2 Double sided triangular insert 32
3.3 (a) DORST uniaxial machine 33
3.3 (b) Triangular inserts 33
3.3 (c) Pre-press alumina inserts 33
3.4 Wet bag isostatic press machine 35
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3.5
3.6
3.7
3.8
3.9
3.10
3. 11
4.1
4.2
4.3
4.4
4.5
4.6
4.7
4.8
4 .9
N abertherm furnace l 600°C
Firing profile for 1400 °C
Firing profile for 1550 °C
ESEway Digital Vickers Hardness Testers
Dilatometer
Universal Tensile Machine - GOTECH 50 KN
GOTECH Impact Tester
Alumina tringular shaped milling inserts
Density of green product before sintered at 1400°C
Density of green product before sintered at 1550°C
Density of alumina sintered at l 400°C at different pressure
Density of alumina sintered at l 400°C at different pressure
Densification of alumina sintered at temperature l 400°C
Densification of alumina sintered at temperature l 550°C
Percentage of water absorption at sintered temperature of 1400°C
Percentage of water absorption at sintered temperature of l 550°C
36
36
37
39
42
43
45
47
49
50
51
52
53
53
58
58
4.10 Percentage shrinkage alumina powder after CIP press at 15,000 psi 60
4.11 Percentage shrinkage alumina powder after CIP press at 20,000 psi 60
4.12 Percentage shrinkage alumina powder after CIP press at 25,000 psi 60
4.13 Shrinkage percentages versus various pressing pressure and sintering
4.14
4.15
temperature
Shrinkage trends
Thermal expansion data of Alumina TM-DAR
62
62
64
4.16 Vickers hardness value respect to varies pressing pressure and sintered at
temperature l 400°C 65
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4.17 Vickers hardness value respect to varies pressing pressure and sintered at
temperature I 550°C
4.18 Hardness trends respect to pressing pressure and sintering
temperature
66
67
4.19 Flexural strength of alumina TM-DAR respect to pressing pressure and
sintering temperature
4.20 Variation of flexural modulus with pressing pressure and sintering
temperature
4.21 Variation in impact energy respect to pressing pressure and sintering
temperature
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68
69
70
APPENDIX No.
A
B
LIST OF APPENDICES
TITLE
Results of Experiments (Raw data)
Standard Test Method
x
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CHAPTER 1
INTRODUCTION
1.0 Background Study
Isostatic presses are widely used to produce pre-form of high density and
dimensionally precise products. Isostatic presses shall satisfy fabrication of one elongated
dimension products, a complex shape even large volume products (J.S. Reed 1995). One of
product that can be produce by isostatic presses is cutting tools. In the manufacturing
industry, machining is widely used in the production of products. A tool is considered
reliable when it can machined the workpiece with relative ease while producing the desired
range of surface finish. The characteristics of a tool with good machineability are when
less power needed to cut, can cut in a short time, produced good surface finish and less
wear in a short period of usage.
Selection of appropriate cutting tools is very important to produce products with
high dimensional accuracy and surface finish quality. Properties of alumina (Ah03) which
is high hardess, wear resistance and chemical stability makes it become highly suitable as a
research topic to develop its capability as cheap and reliable cutting tool. Ceramic tools
materials with alumina based facing increasing interest as they exhibit high hardness,
thermal resistance and high abrasion resistance, thus making it suitable for high speed
machining (K. Geric 2010).
This project were designed to understand the effect of CIP process on physical
behavior of alumina oxide (Ah03) powder to produce a milling cutting insert with respect
to shrinkage, hardness and densification.
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1.1 Statement of the Purpose
Machining technology facing increasing interest since it improve productivity and
produce better workpiece surface quality. Continual improvements consistantly done either
by increasing the wear resistant or improving the material used to produce the cutting tools.
Development of advanced ceramic tools increasingly active in past decades which ceramic
material can significantly increase the tool life relative to ceramic special qualities. Most of
the research focus on alumina coated with other materials. Basically, less research were
done on fabricating alumina inserts which will be used in milling.
1.2 Problem Statement
Cold isostatic press (CIP) is one of the pressing techniques that available to
manufacture cerannc inserts. Developing ceramic insert through powder technology
involve with various parameters such as pressing pressure, pressing time and grain size of
the alumina powder. These parameters significantly affect the mechanical and physical
properties of compacted product before and after sintering process such as density,
hardness, strength and dimensional accuracy.
High-speed machining technology has already penetrated in most manufacturing
industries to cut various workpiece from steel and alloys to composites. Manufacturing
engineers frequently use high-speed milling to remove the greatest possible quantity of
material from workpiece. However, using high-speed milling leads to the increase of
cutting temperature and soften of the tool material (Liu et al 2002). Therefore, tool material
with high wear resistance take a crucial role in high-speed milling.
Demand on high performance cutting tool lead to production of cutting tool with
low cost. Alternative material shall be studies to replace conventional material used to
produce cutting tool such as carbides, high speed steels and tungsten. Research that has
been done on alumina tool in high speed machining area is mostly on turning machines.
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Unfortunately, studies on alumina cutting inserts for milling process still not many.
Traditional ceramic fabrication used alumina matrix with additives then pressed using hot
pressed. The weakness by using this technique, compromising on the hardness and wear
tool are inevitable. Pressing using cold isostaic gives promising idea on producing alumina
cutting inserts.
1.3 Objectives
The main objectives of this research as follows:
i. To study the effect of CIP parameters on shrinkage, hardness and densification
behaviour of alumina oxide after undergo Cold Isostatic Press process.
11. To develop ceramic cutting insert of alumina oxide (Ah03) using Cold Isostatic
Press.
1.4 Scope
In this research, the scope of this project are outline as follows:
l. Prepress sample using uniaxial press machine, Cold Isostatic Press (CIP) process
and sintering process will be employed in producing the ceramic cutting tool.
2. The material used for ceramic cutting tools will Alumina Oxide (Ah03).
3. The input parameters that will be used are cold isostatic pressing pressure and
sintering temperature.
4. The product to be fabricate according to commercial milling insert with triangular
shape.
5. The output responces to be investigated include shrinkage, hardness, prorsity,
densification and flexural strength behavior of alumina cutting insert.
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CHAPTER2
LITERATURE REVIEW
2.0 Introduction
The trend toward high speed machining, dry cutting and the need of complex
geometry tool cause an increasing demand for ceramic based material as cutting tools for
machining steel based alloys in machining industries nowadays. Because of these reasons,
the ceramic materials such as alumina and zirconia which are well known as hard and
brittle materials are being developed as cutting tools to penetrate the tooling market.
Ceramic engineering or advanced ceramics are inorganic non-metallic materials used in
high-performance engineering applications. It can be categorized as oxide-based ceramics,
carbides, nitrides and borides (Xu & Jahanmir 1996). Among the properties of advanced
ceramics are wear and oxidation resistance, high stability against chemical reaction, stable
against thermal resistance, thermal insulation and electrical insulation. Research and
development of ceramic material are very intensive in order to increase its potential as a
high quality cutting tools. The use of ceramics cutting tool has increased due to its ability
to operate at high temperatures and resistant to oxidation and chemical reactions (Lee
1999).
The needs and interest on ceramic mcrease especially in machining field .
Machining is a metal forming process and preferable technique in manufacturing industry
due to its simple operation and relatively fast in certain aspect. High speed machining
operations require cutting tools that are resistant in terms of temperature and pressure.
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Some common cutting tools used in machining operations include high speed steel,
carbide, ceramic, cement, diamond and cubic boron nitride.
Ceramic cutting tools are considered as a suitable alternative of carbide or high
speed steel. It can perform machining operations on both high and low velocity effectively
(Lo Casto et al. 1996). Among the ceramic cutting tools most widely used in the market is
alumina. Alumina ceramics are among the most notable because it has a high hardness and
high stability against temperature and the chemistry (Xu et al. , 2001 ). It is also cheaper
than ceramic nitrides and carbides (Xu & Jaharnnir 1996). Number of studies has been
done in developing the potential of alumina as cutting tools, particularly in terms of the
strength properties. Presently, there are several kinds of alumina-based composite insertion
tool such as alumina-zirconia, alumina-titanium-carbide, alumina-zircon, alumina-silicon-
carbide (K. Geric 2010, Xu et al. 2001 ).
Cold isostatic press (CIP) is one of the pressing or compaction techniques that
available in the manufacturing of ceramic inserts. Compaction process can produce near
net shape, density, and particle-to-particle contact which make the part sufficiently strong
for further processes (S.Kalpakjian 2001 ). CIP have a wide range of applications such, as a
repair work for casting product or fabrication of metal matrix composite (MMC) and
ceramic matrix composite (CMC). Few researches on CIP process on ceramic powder were
done. Most researches that have been done were focus on other processes such as slip
casting and dry pressing (uniaxial).
This project aims to understand the effect of CIP and sintering process such as
temperature and pressure on the physical behaviour of powder ceramic part with respect to
shrinkage, hardness, density, flexural strength, Modulus of rupture and fracture strength.
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2.1 Ceramic Material
Ceramics are inorganic, non-metalic materials which the metallic and non-metalic
elements bonded together primarily by ionic or covalent bonds. Ceramic divided to three
basic categories:
I. Traditional ceramics: Silicates for clay products such as pottery.
2. New ceramics: non-silicates ceramics such as oxides and carbides. These
categories poses better mechanical or physical properties compared to
traditional ceramics.
3. Glass: based primarily on silica and having non-crystalline structure.
New ceramics material relatively has high strength, high temperature resistance,
high wear resistance and good corrosion resistance. New ceramics further classified into
three distinct categories of oxides, non-oxides and composites. Examples of oxides
ceramics are alumina (Ah03) and zirconia (ZrO). Non-oxides materials are carbides,
borides, nitrides and silicide. Meanwhile composites ceramic are reinforced material and
combinations of oxides and non-oxides.
2.1.1 Properties of Ceramic
In general ceramics are hard, brittle, electric and heat resistance, wear resistance
and chemically inert. Physical properties of various ceramics are shown in Table 2.1.
Generally, ceramic have low density compared to metals but higher than polymers. The
melting temperature of ceramics is higher than most metals. In term of electrical and
thermal conductivity, mostly they are insulators but in certain condition they can be good
conductor. For thermal expansion, most ceramic having less thermal expansion compared
to metals but the effect are more damaging due to brittleness properties of ceramic.
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Table 2. l: Properties of various ceramic at room temperature. (S.Kalpakjian 2001)
Comprc i\'C la tic Material ymbol tren2th Modu lus Hardne, Den ity
(Mpa) ( Pa) (HK) (kg/m 1
)
lumina Oxide Al:?O , 1000-2900 JI 0-410 2000-3000 4000-4 00
Cu bi boron nitride C B ' 7000 50 4000- 000 J480
ilicon nitride Si :; 4 No data J00-310 2000-2500 J300
Si licon carbide SiC 700-J500 240-480 2 100-JOOO 3100
Titanium carbide TiC JI 00-3850 J 10-410 1800-3200 5500-5800
Tung ten carbide WC 4100-5900 520-700 1800--400 I 0000- I 5000
2.1.2 Properties of Alumina
Alumina is an oxide ceramic used either in pure form or as a mixture with other
oxides. Alumina occurs naturally in large quantities and is available via the Bayer process
(J.S. Reed 1995). Naturally, the alumina exists in two forms, namely a-Al203 and y-
Al203. a -Al203 is stable elements when compared with y -Al203. Alumina structure
consists of oxygen ions in the close packed hexagonal structure. In Al203, Al3 + ions are
placed in octahedral interstices makes each ion is surrounded by six 02-ions. Figure 2.6
shows the arrangement of ions in the vicinity of the 02-ions Al3 + in Al203 polyhedron
structure (Callister 2001 ). Alumina is very hard crystalline, having hexagonal close pack
array of oxygen atoms with metal atoms in two-thirds of octahedrally cordinates interstites.
Each metal atom cordinated by six oxyen atoms and each having four metal neighbours
(6:4 coordination). Figure 2.1 show the arrangement of oxygen ion and aluminum ions for
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alumina. Chemical formula of alumina is Ah03 shows the it compounds of aluminium and
oxygen. They are available in concentration of99.5% and 96 % purities. The microstucture
of alumina is shown in Figure 2.2. Structure containing alumina powder is known as
mullite and spinel, which usually used as refractory materials for high temperature
applications. Table 2.2 shows the general specifications of high-purity alumina material.
Figure 2.1 Arrangements of ions of 0 2- AI3+ inside Ah03.
(Source: Callister, 2001)
Figure 2.2: Micrograph of alumina powder. (Source: Callister, 2001)
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Table 2.2 : General properties of alumina powder. (Lo Casto et. al 1996)
Aluminium Oxide 99.9% Purity
General
Molecular formula Ah03
Molar mass l 01.96 g/mol
Properties
Density and phase 3.97 g/cm3, solid
Solubality in water Insoluble
Melting point 2054 °C
Boiling point -3000 °C
Thermal conductivity 18 W/m.K
Hardness - V ikers 18 Gpa
Modulus Elasticity 350 GPa
Thermal Expension 8.5 x 1 o-<>;oc
Fracture Toughness, Kie 4.6 Mpa m1' L
2.2 Cold Isostatic Press
CIP is used extensively in powder metallurgy which include ceramics industry.
Isostatic pressing capable to deligate uniform high pressure to produce parts. The product
is consistent in density throughout their cross sections compared to parts that produced by
uniaxial press. CIP comes in two types; dry bag and wet bag. Dry bag process is molding
powder that filled in a forming rubber mold as shown in Figure 2.3(a). Forming process
done by transmitting pressure through a pressing rubber mold in high- pressure vassel. The
limitation of dry bag CIP is limited to small size parts and simple shapes where products
can be removed easily. In the wet bag press, the pressure vassel is filled with liquid,
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