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MEC2202
Manufacturing processesFaculty of Engineering and Surveying
In t roduc to ry bookSemester 1 2013
Published by
University of Southern QueenslandToowoomba Queensland 4350Australia
http://www.usq.edu.au
© University of Southern Queensland, 2013.1.
Copyrighted materials reproduced herein are used under the provisions of the Copyright Act 1968 as amended, or as a result of application to the copyright owner.
No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means electronic, mechanical, photocopying, recording or otherwise without prior permission.
Produced by the Distance and e-Learning Centre using FrameMaker7.1 on a Pentium workstation.
Table of contents
PAGE
Essential information 1
Introduction 2Personnel 2Course outline 2Course structure 3
Study schedule 6
Assessment 7
Assignment 1 9
Assignment 2 11
Formula sheet for MEC2202 13
Past examination 17
Solutions to selected questions in the past examination paper 27Forming Processes: Part A 27
MEC2202 – Manufacturing processes 1
Essential information
The topics in the following list provide important information that will assist you with your study. You can access a handout containing the information on your StudyDesk through the ‘Essential information (study materials)’ link <http://usqstudydesk.usq.edu.au/file.php/1/sitefiles/DeC/essential_info/essentialhandout.pdf>. You will need your UConnect username and password to access the file. Please make sure you read this information carefully before commencing your study.
• Getting started <http://usqstudydesk.usq.edu.au/file.php/1/sitefiles/DeC/essential_info/getting_started.pdf>
• Course specification <http://usqstudydesk.usq.edu.au/file.php/1/sitefiles/DeC/essential_info/course_specification.pdf>
• Support <http://usqstudydesk.usq.edu.au/file.php/1/sitefiles/DeC/essential_info/support.pdf>
• UConnect<http://usqstudydesk.usq.edu.au/file.php/1/sitefiles/DeC/essential_info/u_connect.pdf>
• Assignment submission<http://usqstudydesk.usq.edu.au/file.php/1/sitefiles/DeC/essential_info/assignment_submission.pdf>
• Grading levels<http://usqstudydesk.usq.edu.au/file.php/1/sitefiles/DeC/essential_info/grading_levels.pdf>
• Course evaluation <http://usqstudydesk.usq.edu.au/file.php/1/sitefiles/DeC/essential_info/course_evaluation.pdf>
• Residential schools<http://usqstudydesk.usq.edu.au/file.php/1/sitefiles/DeC/essential_info/residential_school.pdf>
• Library<http://usqstudydesk.usq.edu.au/file.php/1/sitefiles/DeC/essential_info/library.pdf>
• Referencing APA<http://usqstudydesk.usq.edu.au/file.php/1/sitefiles/DeC/essential_info/apa_referencing_guide.pdf>
• Referencing Harvard AGPS<http://usqstudydesk.usq.edu.au/file.php/1/sitefiles/DeC/essential_info/harvard_referencing_guide.pdf>
• Optional purchase of study materials<http://usqstudydesk.usq.edu.au/file.php/1/sitefiles/DeC/essential_info/optional_purchase.pdf>
• USQ policies and procedures<http://usqstudydesk.usq.edu.au/file.php/1/sitefiles/DeC/essential_info/policies_procedures.pdf>
2 MEC2202 – Manufacturing processes
Introduction
This book is a guide to the course MEC2202 Manufacturing Processes. It contains details of the presentation and assessment of the course, a study programme, assignments to be submitted by the student and other information. You should refer to this book regularly throughout your study of the course.
Personnel
The examiner of the course is Dr Hao Wang.
Dr Wang completed has Bachelor of Engineering in Materials at Nanjing University of Science and Technology, and Master of Science in Materials at the Institute of Metal Research, Chinese Academy of Sciences. He then joined the Shanghai Institute of Ceramics, another institute under the Chinese Academy of Sciences, as a research engineer. He moved to Australia in 1994. After working at Monash University and Comalco Alumunium Ltd for a while, he came to the University of Queensland to conduct his PhD in Materials Engineering. He was an ARC Australian Research Fellow before he came to USQ. His research interests lie on solidification and metal forming, amorphous and nano-structured materials, and bio-materials.
Course outline
A knowledge of manufacturing processes is essential for any student involved in production or design engineering and is highly desirable for students concerned with most other branches of engineering. This is because the method by which a component is produced will always determine, to some degree, its:
• cost
• design and hence its ability to fulfil the function for which it was originally devised
• behaviour in service, since each process has its own inherent defects and characteristic influence on the properties of the metal and/or the manufactured assembly.
Patently, anyone engaged in the field of engineering who utilises components without some regard to their design limitations and potential behaviour in service, is guilty of neglect.
This introductory study cannot attempt to impart the depth of knowledge of manufacturing processes required by those engaged in production or design engineering. For these students, the information presented in this course will be extended in studies of materials and manufacturing conducted in other courses.
The course is presented in two discrete parts as indicated in the course structure. Part A is concerned with forming processes and Part B with metal cutting processes.
A study programme and timetable for the course is given in the study schedule. The two parts of the course should be studied concurrently as indicated.
NB: Formula sheets are provided in this introductory book and at the end of study book 2.
MEC2202 – Manufacturing processes 3
Course structure
Course DVD/video
MEC2202 Manufacturing Processes we have introduced two DVDs titled ‘Casting’ and ‘Plastics’. You may obtain a copy of the DVD/video from the Off-Campus Library Service.
To obtain a copy on loan of this DVD/video log on to DocEx on the Library website. Access can be gained from the USQ website>The Library> Off-Campus Students (under Information For…).
Students in the Toowoomba area could also phone 46312589 to arrange to collect a copy.
Remember: Fines and penalties will be incurred for late return or late renewal of the item on loan. This DVD/Video must be returned to the USQ Library by the end of semester.
Manufacturing processes
PART B
Cutting operations
Thread
manufacturing
processesPrinciples of metal
cutting
Cutting tools for
machining
Abrasive
machining
processes
Milling and
broaching
processes
PART A
Forming
Manufacturing
costs
Casting
processes
Powder
metallurgy
Forming
processes Forming of
plastics,
ceramics &
compositesWelding
processes
Turning, boring
& related
processes
Non traditional
machining
processes
Rapid
prototyping
operations
4 MEC2202 – Manufacturing processes
Program structure
The relationship of this course to others in the Bachelor of Technology and Bachelor of Engineering programmes is illustrated schematically below.
Structure of
Materials
Mechanical
Behaviour of
Materials
Fine
Measurement
Manufacturing
& Production
Systems
Industrial
Engineering
Quality
Assurance
Industrial
Relations
Joining
Processes
Forming
Operations
Cutting
Operations
MEC1201
Engineering Materials
MEC2202
Manufacturing Processes
MEC3203
Materials TechnologyMEC3204
Production EngineeringENG3003
Engineering Management
and
ENG4004
Engineering Management
Science
MEC2202 – Manufacturing processes 5
Direct lecturer contact
You can also contact the lecturers direct with simple technical queries (e.g. difficulty studying topic or doing assignment, not clear on set activity, need more explanation). When you telephone please be specific about the problem you wish to discuss (e.g. diagram on page 39 of Study Book 1: Assignment No. 1, Question 3) and ensure that you have study materials at hand when you make the call. Such a detailed approach could save you time (and money).
H Wang
Tel: (07) 4631 2549
email: [email protected]
Faculty of Engineering and Surveying Fax: (07) 4631 2526
6 MEC2202 – Manufacturing processes
Study schedule
Week Module/TopicPart A
Module/TopicPart B Assessment
1 Introduction
Module 1: Manufacturing costs
2 Manufacturing simulation(Internal students only, details available on StudyDesk for external students)
3 Module 2: Casting process
4 Module 3: Forming process
Reminder: End of week 4 is the last date to drop courses without academic or financial penalty.
5 Module 4: Powder metallurgy
6 BREAK
7 BREAK
8 Module 5: Forming of plastics, ceramics and composites
Assignment 1Due: 15 April 2013
Reminder: End of week 8 is the last date to drop courses without academic penalty.
9 Module 8: Principles of metal cutting
Module 9: Cutting tools
10 Module 10: Turning, boring, drillilng and related processes
11 Module 11: Milling, broaching and sawing processes
Module 12: Abrasive machining processes
12 Module 13: Form generation process
Module 14: Non-traditional machining processes
13 Module 6: Welding processes Assignment 2Due: 20 May 2013
14 Module 7: Rapid prototyping
15REVISION
16–17 EXAMINATION PERIOD
MEC2202 – Manufacturing processes 7
Assessment
The summative assessment of your performance in the course comprises:
Two (2) assignments, each with a value of 150 marks (total 300 marks).
One 2-hour examination with a value of 700 marks. The paper will be divided into two sections. Section A is forming and Section B is cutting. Students need to attempt all questions.
Assessment scheme
Assignments must be posted by the due date or they will not be marked. Because answers to the assignments will be issued immediately after the due date, no requests for extensions of time to complete assignment work will be entertained.
If you are unable to complete an assignment by the due date for reasons beyond your control, e.g. late receipt of study materials, illness, etc. you should advise the examiner in writing. Documentary evidence in the form of a doctor's certificate or a note from your employer should be provided.
Final examination
There is one 2-hour examination in this course. Section A will assess your knowledge of manufacturing costs, forming processes and welding processes whilst Section B will be concerned with cutting operations and numerical control. The paper is a restricted examination; students will be permitted to use a calculator but may not have access to any other materials.
In order to successfully complete the course it will be necessary for students to achieve 50% of the total possible marks for the course and at least 50% of the total marks for the final examination.
A copy of the previous final examination paper with solutions is provided at the end of this introductory book.
Assessment number Objective total
Module objective 1 2 3
1
5
4
2
Assessment total 150 150 700 1000
8 MEC2202 – Manufacturing processes
Notification of results
Your result certificate will be mailed at the end of semester. If you have any queries, send only written enquiries to DeC (no telephone enquiries).
• If you do not satisfactorily complete all of the specified assessment requirements for the course you will receive a FAIL grade.
• In some cases, an INCOMPLETE grade may be awarded. If this is the case, a Statement of Requirement for Further Work will be issued or you may be required to sit for a supplementary or deferred examination.
MEC2202 – Manufacturing processes 9
Assignment 1
Question 1
(75 marks)
A company has a requirement for 25 liquid filters per month, the principal component of which is its cast iron body, see the figure below. Suggest how this casting could be most economically produced, assuming that each month's demand is produced in a single batch.
What are the pros and cons if the part is vertically cast? What will happen if the part is horizontally cast? Draw the side views of the completed mould assemblies for the two options.
Based on your observations, which option (vertically cast or horizontally cast) is better. Explain your choice of option.
Due date: 15 April 2013
Weighting: 15% or 150 marks
Examiner: A/Prof H Wang
Note: Penalty for late submission will be the loss of all marks
10 MEC2202 – Manufacturing processes
Question 2(75 marks)
The following information is known for a broaching machine and a milling machine, each of which could be tooled up to produce a certain component. Assuming straight line depreciation over 10 years,. A 40-hour week is worked over 50 weeks per year. The life of the tools of the two machines is assumed to be over 400 hours.
(a) If 1000 components are produced, what would be the cost per piece using each machine? And which machine should be used?
(b) What is the breakeven point for the manufacture of the component on the two machines? Illustrate the breakeven analysis in graph.
Milling machine Broaching machine
Initial cost $ 8,000 $ 16,000
Tooling cost $ 60 $ 900
Material cost/piece $0.15 $0.15
Labour cost/hour $1.60 $1.00
Cycle time/piece 4 min 1 min
Setter' rate/hour $3.20 $3.20
Setting-up time 3 hours 2 hours
General overhead/hour $7.50 $12.10
MEC2202 – Manufacturing processes 11
Assignment 2
Question 1(90 marks)
Turning is performed on a work material with shear strength of 800 MPa. An orthogonal cutting operation is performed using a rake angle of 10o, depth of cut to=2.0 mm, and the width of cut w=5 mm. The chip thickness ratio is measured after the cut to be 0.5. The coefficient of friction is 1.2.
(a) Determine: (i) chip thickness; and (ii) shear angle.
(b) Determine (i) shear force; (ii) friction angle; and (iii) cutting force. Draw a force diagram to indicate the relationships between these forces.
(c) If the cutting speed is 200m/min, then determine:
(i) power required for cut in kW;(ii) metal removal rate in cm3/min; and(iii) specific power of the material cut.
Question 2
(60 marks)
(a) What is the difference between turning and milling? What is the difference between peripheral milling (slab milling) and face milling?
(20 marks)
(b) What are the five principle parameters of a grinding wheel? Using a commercial wheel as an example to explain how a grinding wheel is specified.
(20 marks)
(c) In grinding process, which are the methods can be used to increase materials removal rates? And which are the methods can be used to improve surface finishing?
(20 marks)
Due date: 20 May 2013
Weighting: 15% or 150 marks
Examiner: A/Prof H Wang
Note: Penalty for late submission will be the loss of all marks
12 MEC2202 – Manufacturing processes
MEC2202 – Manufacturing processes 13
Formula sheet for MEC2202
14 MEC2202 – Manufacturing processes
MEC2202 – Manufacturing processes 15
General Energy
Orthogonal machining Tool life
Turning
V πDN=
MRR Vft=
PuP
MRR-------------=
PPu MRR CF
E-------------------------------=
U Us Uf+=
UFc
ft-----=
UFsVs
ftV-----------
Fs αcos
ft φ α–( )cos--------------------------------= =
Uf
FVc
ftV---------
Frft------= =
φtanr αcos
1 r αsin–-----------------------=
rttc---=
μ βtanFc αtan Ft+
Fc Ft αtan–-----------------------------= =
R Fc2
Ft2
+=
Fc
tb Ss
φsin------------
β α–( )cosφ β α–+( )cos
------------------------------------=
Ft
tb Ss
φsin------------
β α–( )sinφ β α–+( )cos
------------------------------------=
Fs Fc φcos Ft φsin–=
Fn Fc φsin Ft φcos+=
Ss
Fs
As-----=
Astb
φsin-----------=
Ss
Fc φsin φ Ft φsin2–cos
tb--------------------------------------------------------=
Sn
Fn
As------=
Sn
Fc φsin2 Ft φsin φcos+
tb----------------------------------------------------------=
P FcV=
VTn C=
VT C n R 1 n–( )⁄n
=
R J H⁄=
TT R1n--- 1–=
CT L LA+( ) fN⁄=
MRRVtf2
------- for facing=
OfD d–( )2Lt
------------------Lw=
Roughnessf 2
8CR-----------=
CTL LA+( )
fN--------------------=
16 MEC2202 – Manufacturing processes
Drilling Milling
Electrochemical machining Grinding
Broaching Rapid prototyping
Shaping
MRRDVf
4----------=
Power MRR Pu×=
fm ftNn=
CTL LA L0+ +
fm----------------------------=
LA t D t–( )=
MRR wtfm=
tc 2fttD----=
P Pμ MRR×=
frCIA------
CEgr--------
VAt-----= = =
TmLfr---=
MRR frA=
IEAgr-------=
RgrA-----=
t2vNV--------
D d+Dd
------------- f
for internal cylindrical grinding
•=
t2vNV--------
d D–Dd
------------- f
for internal cylindrical grinding
•=
t2vNV--------
fD----=
KPw----
Pf b v××-------------------= =
(
(
)
)
Pitch, P 1.75 Lw=
LB nr ns nf+ +( ) P Lrp Ls+ +=
MRR trnwV=
T i
Ai
vD------- T d+=
T c Ti
i l=
nl
=
V πDNs=
V2 Ns
Rs------------=
MRR wtNs f=
CTw
Ns f---------=
MEC2202 – Manufacturing processes 17
Past examination
A copy of the 2006 examination for this course follows. A perusal of this examination paper should enable you to:
• Note the style of the questions set by the examiners for the course.
• Preview the standard required by the end of the course.
• Test your knowledge, as part of your preparation for the exam.
• Please note that no other past examination papers will be supplied.
18 MEC2202 – Manufacturing processes
MEC2202 – Manufacturing processes 19
UNIVERSITY OF SOUTHERN QUEENSLAND
FACULTY OF ENGINEERING AND SURVEYING
Course No: MEC2202 Course Name: MANUFACTURING PROCESSES
Assessment No: Internal [ X ]
External [ X ]
This examination carries 70 % of the total assessment for this course.
Examiner: DR. H WANG Moderator: DR. H. KU
Examination Date: JUNE/JULY, 2006
Time Allowed: Perusal - Ten (10) minutes Working - Three (3) hours
Special Instructions:
This is a RESTRICTED examination.
Students are permitted to write on the examination paper during perusal time.
Non-programmable calculators are permitted. Students must note the make and model of the calculator used in the examination on the front of the answer book (or examination paper where applicable). This may be subject to checking by the supervisor.
All examination question papers must be submitted to supervisors at the end of every examination and returned to USQ.
One (1) sheet of graph paper is attached.
This examination contains Two parts. Students must attempt all questions.
The value of each question is different and is indicated in the exam paper.
Commence each answer to the questions on a new page of the examination booklet.
Any non-USQ copyright material used herein is reproduced under the provisions of Section 200(1)(b) of the Copyright Amendment Act 1980.
20 MEC2202 – Manufacturing processes
MEC2202 – Manufacturing processes 21
MEC2202 MANUFACTURING PROCESSES JUNE/JULY 2006 Page 1 __________________________________________________________________________________________
Page 1 of 5
Part A: Forming Processes
QUESTION 1 (100 marks)
The following information is known for a component that can be produced with equal facility upon either of the two machines cited.
Capstan Single spindle Lathe automatic
Tooling cost $600 $3,600
Setting up time 1 hour 8 hours
Tool setter’s rate per hour $8.00 $8.00
General overheads per hour (including depreciation costs) $30.0 $40.0
Material cost per component $1.00 $1.00
Time to produce one component 5 min. 1 min.
Direct labour cost per hour $10.00 $5.00
(a) If the component can be sold for $5 each, what is the breakeven point for each machine? illustrate the break even analysis in graph. (50 marks)
(b) If 1000 components are required, which machine should be used and what would be the cost per component? How about if 2000 components are required? (50 marks)
QUESTION 2 (100 marks)
(a) Compare to the multiple-use mould casting processes, what are some major advantages and disadvantages of sand casting? Describe the process steps in sand casting? (30 marks)
(b) Describe the process steps in investment casting? (20 marks)
(c) What are some of the more attractive features of die casting process compared to sand casting? (20 marks)
(d) Describe the process of low pressure die casting and high pressure die casting. Comparing these two processes, what are the most attractive features for each process? (30 marks)
22 MEC2202 – Manufacturing processes
MEC2202 MANUFACTURING PROCESSES JUNE/JULY 2006 Page 2 __________________________________________________________________________________________
Page 2 of 5
QUESTION 3 (100 marks)
(a) What are the three main hot working processes? Describe each process. (40marks)
(b) What are four main cold working processes? When designing parts to be shaped by bending, what are the two main factors need to be considered? (30 marks)
(c) What is the main difference between hot working and cold working? List at least two advantages and two disadvantages of cold working. (30 marks)
QUESTION 4 (100 marks)
(a) How does the fabrication of a thermoplastic polymer differ from the processing of a thermosetting polymer? (20 marks)
(b) In what ways is injection moulding of plastic similar to die casting of metals? (20 marks)
(c) What are the basic two classes of ceramic materials, and how does their processing differ? (20 marks)
(d) What are the advantages and disadvantages of powder metallurgy? Compare briefly the relative merits of powder metallurgy and low pressure die casting as means of producing small engineering components. (20 marks)
(e) Define “heat affected zone” in welding? Why preheating is sometime performed? (20 marks)
MEC2202 – Manufacturing processes 23
MEC2202 MANUFACTURING PROCESSES JUNE/JULY 2006 Page 3 __________________________________________________________________________________________
Page 3 of 5
Part B: Cutting Processes
QUESTION 5 (140 marks)
(a) In the orthogonal cutting operation the following data applies:
Feed rate = 0.20 mm/rev Depth of cut = 2.0 mm Cutting speed = 200 m/min Cutting force =1800 N Normal force = 900 N Tool rake angle = 5o
Chip thickness ratio = 0.4
Sketch the orthogonal machining process and force diagram (40 marks) and find:
i) chip thickness; (10 marks) ii) shear plane angle; (10 marks) iii) resultant force; (10 marks) iv) power required for the cut in kW; (10 marks) v) metal removal rate in cm3/min (10 marks) vi) specific power of the material cut in KW/cm3/min. (10 marks)
(b) What variables or factors need to be considered in machining operation? (40 marks)
QUESTION 6 (80 marks)
(a) What is the tool-workpiece movement relationship in turning? What is the difference between turning and boring? (20 marks)
(b) What is the basic difference between facing and parting (cut-off) in turning operation? (20 marks)
(c) What functions are performed by flutes on a drill? What can happen when an improperly ground drill is used to drill a hole? (20 marks)
(d) What are the parameters that need to be considered for abrasives? Describe the different possible interaction between grit and workpiece during abrasive machining.
(20 marks)
24 MEC2202 – Manufacturing processes
MEC2202 MANUFACTURING PROCESSES JUNE/JULY 2006 Page 4 __________________________________________________________________________________________
Page 4 of 5
QUESTION 7 (80 marks)
(a) What are the three broad categories of milling? What are the two common ways of classifying milling cutters? (20 marks)
(b) Explain what steps are required to produce a T-slot (such as that found in milling machine table) by milling. (20 marks)
(c) What are the basic features of saw blades? (20 marks)
(d) What are the main parameters we use to describe the profile of a thread? How to cut threads on a lathe? (20 marks)
MEC2202 – Manufacturing processes 25
MEC2202 MANUFACTURING PROCESSES JUNE/JULY 2006 Page 5 __________________________________________________________________________________________
Page 5 of 5
END OF EXAMINATION
26 MEC2202 – Manufacturing processes
MEC2202 – Manufacturing processes 27
Solutions to selected questions in the past examination paper
Forming Processes: Part A
Question 2(100 marks)
(a) Advantages (any 2 of the 3):
• Low cost for the initial set-up, eg dies or moulds, suitable for small production volume• No restriction on component size, therefore can be used for large component• No restriction on metal melting point, component size, therefore can be used for higher
melting point ferrous metals.
Disadvantages (any 2 of the 4):
• Need a separate mould for each casting. Can be costly if the production volume is high, it can also cause dimensional and property variation from casting to casting.
• Surface finishing is low• Low cooling rate usually lead to coarse microstructure • Low productivity.
Process steps (at least 1, 3, 4, 5 and 6):
1. Patten making2. sand preparation3. mould and core making4. melting raw materials5. pouring melt to mould6. After solidification and cooling, removal of sand mould7. cleaning and inspection.
(b) Process steps (at least 1, 3, 5, 7 and 8):
1. make wax pattern2. several patterns are attached to a sprue to form a pattern tree3. coat the pattern tree with a thin layer of refractory materials 4. The full mould is formed by covering the coated tree with sufficient refractory
materials to make it rigid5. hold the mould in an inverted position, heat it to melt the wax and let it drip out of the
cavity6. preheat the mould to eliminate all contaminants. 7. pour the molten metal and let it solidify. 8. break away the mould and separate the castings from the sprue.
(c) (any 3 of the 5)
1. reusable mould2. good surface finish3. good dimensional accuracy4. fast cooling rate to produce a strong structure 5. high productivity.
28 MEC2202 – Manufacturing processes
(d) In low pressure die casting, the liquid metal is forced into the cavity under low pressure---approximately 0.1MPa ---from beneath so that the flow is upwards. The advantage of this approach over traditional pouring is that clean molten metal from the centre of the ladle is introduced into the mould, rather than metal has been exposed to air. Gas porosity and oxidation defects are thereby minimized and mechanical properties are improved.
In high pressure die casting, the molten metal is injected into mould cavity under high pressure. Typical pressures are 7 to 350 MPa. The pressure is maintained during solidification, after which the mould is opened and the part is removed. The use of high pressure is the most notable feature. There are two main types of high pressure die casting: hot-chamber and cold chamber. The advantages of high pressure die casting are high production rate, thin section are possible.
Question 3
(100 marks)(a) Rolling, forging and extrusion.
Rolling is a deformation process in which heated metal is passed between two or (more) rolls which rotate in opposite direction. The thickness of the work is reduced by compressive forces exerted by two opposing rolls. The rolling equipment is called rolling mills. The high investment cost requires the mills to be used for production in large quantities of standard items.
Forging is a deformation process in which the work is compressed between two dies, using either impact or gradual pressure to form part. The process is further sub-divided into open-die forging, impression-die forging and press forging.
Extrusion is a compression forming process in which a pre-heated billet is placed into a container and isforced through a die of the required section to produce long lengths of uniform cross-sectional shape. Almost any cross-sectional shape can be extruded. The process is used primarily for non-ferrous metals. The dimensional tolerances of extrusion are very good.
(b) Squeezing, shearing, drawing and bending.
Minimum bend radius. It depends on the ductility of the metal.
The length of a flat blank that will produce a bent part of the desired dimensions.
(c) Hot working is performed above the crystallization temperature of the metal. The recrystallization temperature varies greatly for different metals, being below room temperature for lead and above 550oC for plain carbon steel. While cold working is performed under the recrystalization temperature.
Advantage (any 2 of the 3):
1. close dimensional tolerances are possible2. good surface finish is maintained3. improved strength maybe achieved by work hardening.
Disadvantages (any 2 of the 3):
1. large forces are required, and tooling and equipment are therefore expensive. 2. there is a limit to the amount of deformation that is possible before intermediate
annealing treatment is required.3. it often leaves residual stress in the metal.