MOHD AZRIL AMIL

Office : 2-29
E-mail : azril@unisel.edu.my
A company must
produce products
in an optimal way
to compete in
today’s global
marketplace.
A knowledge of the basic
manufacturing processes is
essential for a successful
engineer in today’s global
marketplace.
 What do engineers do?
Research

Design Products

Manufacture Products

Manage Departments
and Companies
Manufacturing Engineer
Select and coordinate specific processes and
equipment
Industrial Engineer
Responsible for the manufacturing system
design
Materials Engineer
Develop and select materials based on desired
material properties and manufacturing
processes
What is a manufacturing process?
Manufacturing Process
A sequence of operations and processes
designed to create a specific product
The process of turning materials into a
product

©iStockphoto.com ©iStockphoto.com ©iStockphoto.com

1. Material removal

2. Deform or shape material

through heat or pressure

3. Join two or more materials

Products and Manufacturing
Product Creation Cycle
Design → Material Selection → Process
Selection → Manufacture → Inspection →
Feedback
Typical product
cost breakdown
1. Sawing
2. Drilling
3. Milling
4. Turning (Lathe)
5. Abrasive finishing
1. Casting
2. Rolling/Forging
3. Extrusion/Drawing
4. Sheet metal forming
5. Powder metal processes
1. Welding
2. Brazing
3. Soldering
4. Adhesive bonding
5. Fastening
In one step raw materials are transformed into a
desirable shape
Parts require finishing processes
Excess material is recyclable

©iStockphoto.com
A mold is created – A cavity that holds the molten
material in a desired shape until it is solidified
Multiple-use mold
Single-use molds
Material is heated to a specified temperature
Molten material is poured into a mold cavity
Molten material solidifies into the shape of the cavity
Casting or mold is removed
Casting is cleaned, finished, and inspected
Utilizes material that has been cast
Modify the shape, size, and physical
properties of the material
Hot and cold forming

©iStockphoto.com ©iStockphoto.com
Rolling – Material passes through a series of
rollers, reducing its thickness with each pass

Forging – Material is shaped by the controlled

application of force (blacksmith)
Extrusion – Material is compressed and forced
through a die to produce a uniformed cross section

Wire, rod, and tube drawing – Material is pulled

through a die to produce a uniformed cross section

©iStockphoto.com
Cold forming and forging – Slugs of material
are squeezed into dies
Controlled removal of material from a part to
create a specific shape or surface finish
Cutting element is used
Movement must exist between the part and
cutting element

©iStockphoto.com
Operations that create cylindrical parts
Work piece rotates as cutting tool is fed into
the work

©iStockphoto.com

©iStockphoto.com
Lathes and turning centers
Processes include: Straight, taper, contour
turning, facing, forming, necking, parting,
boring, threading, and knurling

©iStockphoto.com ©iStockphoto.com
 Machining Processes

Operations that create flat or curved

surfaces by progressively removing
material
Cutting tools rotate as the work piece is
secured and fed into the tool
 Machining Processes

Mills – Vertical and horizontal

Processes include: Surfacing, shaping,
forming, slotting, T-slotting, angle, straddle,
dovetailing, and slab milling
 Machining Processes

Operations that create holes

Cutting tools rotate and are fed into
nonmoving secured work pieces
 Machining Processes

Drilling and boring machines

Processes include: Drilling, counter drilling,
step drilling, boring, counter boring,
countersinking, reaming, spot facing, and
tapping
 Machining Processes

Operations that break unwanted material away

from the part
A material is placed between a stationary and
movable surface. The movable surface (blade,
die, or punch) applies a force to the part that
shears away the unwanted material.
 Machining Processes

Automated hole punch, squaring shear, and

rotary cutter
Processes include: Shearing, blanking, cutoff,
and parting; punching, perforating, and slotting;
notching, lacing, and trimming
 Machining Processes

Operations in which small particles of materials

(abrasives) remove small chips of material upon
contact
Drum, disc, and belt sanders; surface, vertical
and horizontal spindle; disc grinders; media
blaster; tumblers
 Machining Processes

Operations that cut and shape materials

through chemical means
No mechanical force is used
Electrical discharge, electrochemical,
chemical, laser, electron beam, flame
cutting, and plasma-arc cutting
Processes include: Grinding, sawing,
cutting, machining, milling, blanking, and
etching
Can you think of a product with only one
part?
Most products consist of multiple parts that
are assembled to form a finished product.
Typical assembly processes include:
Mechanical fastening; soldering and
brazing, welding; adhesive bonding
Mechanical Fastening
Use physical force to hold parts together
Mechanical fasteners or part design
Screws, bolts, nails, rivets, cotter pins,
retaining clips, and edge design

©iStockphoto.com ©iStockphoto.com
Welding
Operations that use heat, pressure, or both
to permanently join parts
Gas, arc, stud, spot, forge, roll laminating,
resistance, and induction welding

©iStockphoto.com ©iStockphoto.com
Adhesive bonding
Bonding of adjoining surfaces by filling the
gap between each surface with a bonding
material
Glue, cement, thermoplastic, thermosetting,
and elastomers

©iStockphoto.com ©iStockphoto.com
Soldering and Brazing
Operation in which metal surfaces are
bonded together by an alloy
Heated molten alloy flows between the
adjoining surfaces
When the heat is removed, the molten
metal solidifies and the metal surfaces are
bonded

©iStockphoto.com
Additive process
Parts are produced directly from software
applications
Common rapid prototyping systems include:
stereolithography (SLA), selective laser
sintering (SLS), fused deposition modeling
(FDM), laminated object manufacturing
(LOM), digital light processing (DLP)
Finished parts can be field tested depending
upon building material
Created parts can be used to create a mold
Modifications to design can be implemented
quickly
In calculus there is usually only one
correct answer to a problem.

In manufacturing there are usually

many ways to make a part, some
ways are better than others
In manufacturing there are usually many ways
to make a part, some ways are better than
others.
Factors that must be considered.

Cost Quality
Safety
Equipment
Quantity
available
A company must produce products in an
optimal way to compete in today’s
global marketplace.

On all tests and quiz questions

you are expected to give an
optimal answer to a question, not
just an answer that will work.
How can you
sharpen a
wooden
pencil?
 How can you sharpen a
wooden pencil?
Knife or other sharp object
Sand or abrasion
Toy pencil sharpener
Hand pencil sharpener
Electric pencil sharpener
Automated pencil sharpener
How can you sharpen a wooden pencil?

Situation
You are taking a timed test

You are in your dorm room

You are designing a department office

You have 500,000 pencils that are to be

packaged with a crossword puzzle
Mechanical Properties

KMS 2243
 Mechanical Properties of Metals
How do metals respond to external loads?

 Stress and Strain

 Tension
 Compression
 Shear
 Torsion
 Elastic deformation

 Plastic Deformation
 Yield Strength
 Tensile Strength
 Ductility
 Toughness
2
 Hardness
 Introduction
How materials deform as a function of applied load

Testing methods and language for mechanical
properties of materials.

Stress, 
(MPa)

3 Strain,  (mm / mm)

 Types of Loading
Tensilev Compressive

Shear

Torsion

4
 Forces and Responses
• Tensile – applied loads “pull” the
sample
 Tensile Forces
Gripping Zone Gripping Zone
Failure Zone

¾
½ inch inch

8 ½ inches
 Forces and Responses
– Compression – applied loads “squeeze” the
sample
 Stress
(For Tension and Compression)

To compare specimens , the load is calculated

per unit area.
Stress:  = F / Ao
F: is load
A0: cross-sectional area

A0 8perpendicular to F before application of the

load.
 Strain
(For Tension and Compression)

Strain:  = l / lo ( 100 %)
l: change in length
lo: original length.

Stress / strain = / 
9
 Forces and Responses
• Shear – applied loads are offset
 Forces and Responses
• Torsion – applied loads “twist” the
sample
 Shear and Torsion

Shear stress:  = F / Ao
F is applied parallel to upper and
lower faces each having area A0.

Shear strain:  = tan ( 100 %)

 is strain angle
Shear Torsion

12
 Torsion
Torsion: like shear.

Load: applied torque, T

Strain: angle of twist, .
Torsion
Shear

13
 Mechanical Behavior
• Impact (toughness) –
applied loads “hit” the sample
• Impact (charpy, dart)
 Elastic Solid
• Stress-strain
• What happens when force is removed?
– Recovery
 Stress-Strain Behavior
(Tension)
Elastic Plastic Elastic deformation
Reversible:
( For small strains)
Stress

Stress removed  material

returns to original size

Plastic deformation
Irreversible:
Strain
Stress removed  material
does not return to original
16
dimensions.
 Elastic deformation
Gives Hooke's law for Tensile Stress
 = E
E = Young's modulus or modulus of elasticity (same
units as , N/m2 or Pa)

Unload
Stress

Slope = modulus of
elasticity E

Load

Strain

17 Higher E  higher “stiffness”

 Plastic deformation
(Tension)

Plastic deformation:
• stress not proportional to strain
• deformation is not reversible
18
• deformation occurs by breaking and re-
arrangement of atomic bonds (crystalline
 Tensile Strength
If stress maintained specimen will break

Fracture
Strength
Stress, 

“Necking”
Tensile strength =
max. stress
(~ 100
Strain, 
- 1000 MPa)

Yield stress, y , usually more important than tensile

strength.
19
Once yield stress has been passed, structure has
deformed beyond acceptable limits.
 Mechanical Properties of Metals

Yield strength and tensile strength vary with thermal

and mechanical treatment, impurity levels, etc.
Variability related to behavior of dislocations (Elastic
moduli are relatively insensitive)
Yield and tensile strengths and modulus of
elasticity: Decrease with increasing temperature.
Ductility
20
increases with temperature.
Thank You
Manufacturing
Process
KMS 2243
Basic principle of Metal Casting

1
Metal Casting Processes

Casting

Multiple-use/ Expendable
Permanent Mould Mould

Die Investment Sand

Casting Casting Casting

2
3
4
Introduction to metal casting…
– The only metal manufacturing process which use liquid
metal.
– It requires preparation such as cavity (refractory
material which is closely resemble the final product.
– Molten metal →poured into refractory mould cavity and
allowed to solidify.
– Object is removed from the mould after solidification.
– Universally used to manufacture wide variety shapes of
products.
– Principal Process → Sand Casting (Refractory material)
– Suitability of process → small & large scale production
– Others → Shell mould, Investment, Permanent, Die
cast, etc.
5
Casting

Refractory mold  pour liquid metal  solidify, remove  finish

• VERSATILE: complex geometry, internal cavities, hollow sections

• VERSATILE: small (~10 grams)  very large parts (~1000 Kg)

• ECONOMICAL: little wastage (extra metal is re-used)

• ISOTROPIC: cast parts have same properties along all directions

Advantages…

• Any intricate shapes, internal or external can be

made with the casting process. (Metal flows to any small
section in the mould cavity)
• Possible to cast ferrous and non-ferrous materials.
• Tools required are simple and inexpensive.
• Suitable for trial production or small scale
production.
• Casting of any sizes and weights, even up to 200
tonnes can be made.

7
Disadvantages…
• Low dimensional accuracy.
• Relatively less surface finish than other process.
(regarding to certain process).
• Defects of certain materials are prone to occur due to
moisture contents in [sand casting].

Applications
• Automotive
– Cylinders blocks, piston, piston rings, wheels (rims).
• Machine tools
– M/c tools beds, mill rolls.
• Piping
– Various types of supply pipes.

8
Different Casting Processes

Process Advantages Disadvantages Examples

Sand many metals, sizes, shapes, cheap poor finish & tolerance engine blocks,
cylinder heads
Shell mold better accuracy, finish, higher limited part size connecting rods, gear
production rate housings
Expendable Wide range of metals, sizes, patterns have low cylinder heads, brake
pattern shapes strength components
Plaster mold complex shapes, good surface non-ferrous metals, low prototypes of
finish production rate mechanical parts
Ceramic mold complex shapes, high accuracy, small sizes impellers, injection
good finish mold tooling
Investment complex shapes, excellent finish small parts, expensive jewellery

Permanent good finish, low porosity, high Costly mold, simpler gears, gear housings
mold production rate shapes only
Die Excellent dimensional accuracy, costly dies, small parts, gears, camera bodies,
high production rate non-ferrous metals car wheels
Centrifugal Large cylindrical parts, good Expensive, few shapes pipes, boilers,
quality flywheels
Sand Casting

Cross section of a sand mould

10
11
VIDEO

Sand Casting 1

12
Sand Casting Teminology

• Flask – Holds the sand mould intact, made out of wood for
temporary use.

• Pattern – A replica of the final object with some modifications.

(Providing mould cavity)

• Parting line – Dividing line between the two mould flask (sand
mould). A dividing line between the two halves.

• Bottom board – Made of wood where the mould would start-

up.

• Facing sand – Small amount of fine carrbonaceous material

sprinkled on the inner surface of the moulding cavity (better
casting surface finish).

13
Sand Casting Terminology
• Moulding sand – Refractory material used for making the
mould cavity. (mixture of silica, clay & moisture in appropriate
proportion)

• Backing sand – Largest portion of refractory material in the

moulding sand. Consist of used & burnt sand.

• Core – Making & providing hollow cavities in castings.

• Pouring basin – Small funnel shaped cavity on top of the
mould. (Pouring molten metal)

• Sprue – Passage for the molten metal to reach the mould cavity.
(Controlling the flow of molten metal)

• Runner – Passage in the parting line which the molten metal

flow. (Regulates the flow before reaching the cavity.

14
Sand Casting Terminology
• Gate – Entry point through which molten metal enters mould
cavity.

• Chaplet – Used to support cores in the mould cavity, to

overcome metallostatic forces. (Normally fuse together with the
molten metal.)

• Riser – Reservoir of molten metal in the casting, providing hot

metal to flow back into the mould cavity when there is a
reduction in volume of metal due to solidification.

• Chills – Metallic objects placed in the casting, providing

uniform cooling rate.

• Vents – placed in moulds to carry off gases produced during

casting process. (Exhaust system)

KMS2243 - Turning - MDAR 15

Expendable-Mould Casting Process

• Usually made of sand, plaster and ceramic.

• Traditional method for casting metals.

• Making a cavity in sand with a pattern, removing the

pattern, and filling the cavity with molten metal.

• After casting solidified moulds are broken to

remove casting

• E.g. Sand casting, Shell moulding, Precision

Investment casting

16
Sand Casting

Sand moulding making procedure

17
Sand Casting
• The process,
– A pattern is placed between drag & cope halves of the flask.
– Sand are mixed with other materials (e.g. clay & water) to
improve mouldability & cohesive strength (a.k.a GREEN
SAND).
– Bottom board is positioned on top of the packed sand, the
mould is turned over.
– The cope half of the mould is then packed with sand.
– Mould is opened, pattern is then removed.
– Later on, mould is reassembled and molten metal is poured
through the sprue.
– Leave to solidified & cool.
– The content are shaken from the flask & the metal segment
is separated from the sand.

18
Basics of Sand Casting Process

Moulding
Heat
Treatment

Sand Mould

Melting of Pouring Cleaning

metal Casting & Inspection
Into mould
Finishing

(Shakeout)
Additional Defects,
Furnaces Solidification Removal of
Heat
Risers & Pressure Tightness
treatment
Gates Dimensions

19
20
 VIDEO

Sand Casting 2

KMS2243 - Turning - MDAR 21

Sand Casting – Sand Types
• Green sand
– Given the name due to the moisture content.
– The most common moulding sand used. (least expensive
methods of making moulds)
– Rapid productions.
– Sand moistened with water binder.
– Useful for providing intricate casting configurations.

• Dry sand
– Utilising organic binders, moisture are completely removed
by heating the mould in an oven.
– Providing harder & stronger mould with less tendency for
mould gases to form.
– Useful for providing better surface finish, higher
dimensional accuracy and cater heavy casting.

22
Sand Casting
 Sand Casting

cope: top half

drag: bottom half

core: for internal cavities

pattern: positive

funnel  sprue 
 runners  gate 
 cavity 
 {risers, vents}
Sand Casting Considerations

(a) How do we make the pattern?

[cut, carve, machine]

(b) Why is the pattern not exactly identical to the part shape?

- pattern  outer surfaces; (inner surfaces: core)

- shrinkage, post-processing

(c) parting line

- how to determine?
 Sand Casting Considerations..

(d) taper

- do we need it ?

(e) core prints, chaplets

- hold the core in position

- chaplet is metal (why?) chaplet

Mold
cavity

(f) cut-off, finishing

 VIDEO

Sand Casting 3 (Complex)

KMS2243 - Turning - MDAR 27

Sand Castin Simulation

28
Shell Moldings (Dump-Box
technique)

Shell Moulding Procedure

29
30
Shell Molding
• To make very thin section→ as low as 0.25mm
• Work principle..
– Sand are mixed with thermosetting resin
– Then allowed to come into contact with a heated
metallic pattern plate.
– A thin and strong shell of mould would formed
around the pattern.
– Shell is then removed from the pattern, cope &
drag.
– Assemble→ in the flask with necessary backup
materials. (withstand pressure – molten metal)

31
Shell molding

32
Shell Moulding
• Advantages
– Having more dimensional accuracy than sand
casting. Tolerance of ±0.25mm.
– Better / smoother surface finish could be
obtained. (by using finer grain size)
– Cost reduction→ Possibility of using less amount
of material (sand-resin mixtures).
– Involving simple process.

33
Shell Moulding
• Disadvantages
– Cost of patterns are relatively expensive. Unless
for large scale production.
– Limited casting sizes. (depends on the tumbler
(dump box size)
– Highly complicated shapes cannot be obtained
– Equipment needed for handling are much
complicated.
• Application
– Cylinder & Cylinder heads (IC engines)
– Automotive transmission parts. (brakes assembly)
– Small crank shafts

34
Precision Investment casting
Investment casting (lost wax process) procedure.

35
36
37
38
Precision Investment casting
• A type of an expendable pattern.
– Using molten wax as the pattern material.
– Molten wax injected into a metallic die having cavity of the
cast pattern.
– Wax then allowed to solidify → producing the product
pattern (including gates, runners & other details).

• Preparing the mould

– Pattern dipped into a slurry made by suspending fine
ceramic materials in a liquid mix.
– Excess liquid allowed to drain off from the pattern.
– Refractory grains (fused silica & zircon) are stuccoed to the
liquid ceramic coating. Creating small shell around the
pattern.

39
Precision Investment casting
– Dipping process is repeated until required shell thickness
achieved (6 to 15 mm).
– Shell Thickness depends → cast shape, mass, type of
ceramic & binder used.
– Pattern is removed from the mould (by heating & melting
the wax pattern).
– The mould with cavity is then further heated (100→1000C)

• Applications
– Producing vanes & blades of gas turbines (aerospace
engines)
– Wave guides for radars.
– Bolts & triggers for fire arms.
– Impellers of turbo units.

40
 Investment Casting

KMS2243 - Turning - MDAR 41

Investment Casting

42
Precision Investment casting
• Advantages
– Possibility to produce complex shapes that is difficult by
other method.
– Cast of fine details & thin sections are possible.
– Producing cast of better tolerance & better surface finish
(possible by using fine grain of sand on the mould/casting
interface.)
– Casting are ready for use with minimal machining. (Useful
for hard to machine materials).
– No parting line → Dimensions across would not vary.

• Limitations
– Normally limited by the size & mass of the casting.
– Expensive→ large manual labour involved for pattern &
mould preparation

43
 Die Casting
A permanent mold casting process in which molten
metal is injected into mold cavity under high
pressure
• Pressure is maintained during solidification, then
mold is opened and part is removed
• Molds in this casting operation are called dies;
hence the name die casting
• Use of high pressure to force metal into die cavity is
what distinguishes this from other permanent mold
processes
Hot-Chamber Die Casting
Metal is melted in a container, and a piston injects
liquid metal under high pressure into the die
• High production rates
o 500 parts per hour not uncommon
• Applications limited to low melting-point metals that
do not chemically attack plunger and other
mechanical components
• Casting metals: zinc, tin, lead, and magnesium
 Die Casting Machines
• Designed to hold and accurately close two mold
halves and keep them closed while liquid metal is
forced into cavity
• Two main types:
1. Hot-chamber machine
2. Cold-chamber machine
Hot-Chamber Die Casting
• Hot-chamber
die casting
cycle: (1) with
die closed and
plunger
withdrawn,
molten metal
flows into the
chamber
Hot-Chamber Die Casting
• (2) plunger forces
metal in chamber to
flow into die,
maintaining pressure
during cooling and
solidification.
Hot-Chamber Die Casting
• (3) Plunger is
withdrawn, die is
opened, and
casting is
ejected
Die Casting (Hot Chamber Process)

Schematic of a hot chamber die casting machine

50
Hot-Chamber Die Casting

51
Hot-Chamber Die Casting

52
Die Casting (Hot Chamber Process)

Operation sequence of hot chamber process

53
 Cold-Chamber Die
Casting Machine
Molten metal is poured into unheated chamber from
external melting container, and a piston injects
metal under high pressure into die cavity
• High production but not usually as fast as
hot-chamber machines because of pouring step
• Casting metals: aluminum, brass, and magnesium
alloys
• Advantages of hot-chamber process favor its use
on low melting-point alloys (zinc, tin, lead)
 Cold-Chamber Die
Casting Cycle
• (1) With die closed and ram withdrawn, molten
metal is poured into the chamber
 Cold-Chamber Die
Casting Cycle
• (2) Ram forces metal to flow into die, maintaining
pressure during cooling and solidification
 Cold-Chamber Die
Casting Cycle
• ;(3) Ram is withdrawn, die is opened, and part is
ejected
Cold-Chamber Die
Casting

58
 Cold-Chamber Die
Casting

KMS2243 - Turning - MDAR 59

 Die Casting:
Advantages and
Limitations
• Advantages:
o Economical for large production quantities
o Good accuracy and surface finish
o Thin sections possible
o Rapid cooling means small grain size and
good strength in casting
• Disadvantages:
o Generally limited to metals with low metal
points
o Part geometry must allow removal from die
 Molds for Die Casting
• Usually made of tool steel, mold steel, or maraging
steel
• Tungsten and molybdenum (good refractory
qualities) used to die cast steel and cast iron
• Ejector pins required to remove part from die when
it opens
• Lubricants must be sprayed onto cavity surfaces to
prevent sticking
Metal Forming
MOHD AZRIL AMIL
Traditional Manufacturing Processes

Casting

Forming

Sheet metal processing

Powder- and Ceramics Processing

Plastics processing

Cutting

Joining

Surface treatment
 Forming

Any process that changes the shape of a raw stock

without changing its phase

Example products:
Al/Steel frame of doors and windows, coins, springs,
Elevator doors, cables and wires, sheet-metal, sheet-
metal parts…
Rolling

Hot-rolling

Cold-rolling
Rolling

Important Applications:

Steel Plants,
Raw stock production (sheets, tubes, Rods, etc.)
Screw manufacture
 Rolling Basics

Sheets are rolled in multiple stages (why ?)

tf Vf Vf
to to tf
Vo
Vo

stationary die
Screw manufacture:

rolling die
thread rolling machine

Reciprocating flat thread-rolling dies

Video
Hot Rolling
• metalworking process that occurs above the recrystallization
temperature of the material.
• The starting material is usually large pieces of metal, like semi-finished
casting products, such as slabs, blooms, and billets.
• material starts at room temperature and must be heated. (gas- or oil-
fired soaking pit for larger workpieces and for smaller
workpieces induction heating is used)
• Hot rolled metals generally have little directionality in their mechanical
properties and deformation induced residual stresses.
• While the finished product is of good quality, the surface is covered
in mill scale, which is an oxide that forms at high-temperatures. It is
usually removed via pickling or the smooth clean surface process, which
reveals a smooth surface.Dimensional tolerances are usually 2 to 5% of
the overall dimension.
• Hot rolled mild steel seems to have a wider tolerance for amount of
included carbon than cold rolled, making it a bit more problematic to
use as a blacksmith. Also for similar metals, hot rolled seems to typically
be less costly.
• Hot rolling is used mainly to produce sheet metal or simple cross
sections, such as rail tracks.
Cold Rolling
• Cold rolling occurs with the metal below its recrystallization
temperature (usually at room temperature), which increases
the strength via strain hardening up to 20%.
• It also improves the surface finish and holds
tighter tolerances.
• Commonly cold-rolled products include sheets, strips, bars,
and rods; these products are usually smaller than the same
products that are hot rolled.
• Cold rolling cannot reduce the thickness of a workpiece as
much as hot rolling in a single pass.
FORGING
 Forging

[Heated] metal is beaten with a heavy hammer to give it the required shape

Hot forging,

open-die
Modern Forging
Stages in Open-Die Forging

(a) forge hot billet to max diameter

(b) “fuller: tool to mark step-locations

(c) forge right side

(d) reverse part, forge left side

(e) finish (dimension control)

[source:www.scotforge.com]
Stages in Closed-Die Forging

[source:Kalpakjian & Schmid]

Impression-die and closed-die forging
Quality of forged parts

Surface finish/Dimensional control:

Better than casting (typically)

Stronger/tougher than cast/machined parts of same material

[source:www.scotforge.com]
 Extrusion

Metal forced/squeezed out through a hole (die)

[source:www.magnode.com]

Typical use: ductile metals (Cu, Steel, Al, Mg), Plastics, Rubbers

Common products:

Al frames of white-boards, doors, windows, …

Extrusion
• Working principle…?
– Process of confining the metal in a closed cavity &
allowing it to flow from only one opening.
► metal to take shape of the opening. (resemble the
cross-section of the product)

KMS2243 - Extrusion - MDAR

26
Extrusion: Schematic, Dies

chamber die

extruded shape
hydraulic
stock
piston

chamber

Exercise: how can we get hollow parts?

Extrusion
 Extrusion

• Benefits… ?
– Possible to creating components – having constant cross-
section over any length as can be done by rolling
process.
– More complex products could be obtained than rolling
process.
– Die design ► simple and easier to fabricate.
– Single pass process ►large amount of material cross-
section reduction are possible.
– Brittle materials could easily extruded.
– Possible to produce sharp corners / re-entrant angles.
Extrusion
• Benefits… ?
– Possible to get shapes with internal cavities – Spider dies.
– Excellent ► manufacture large Ø, thin walled tubular products with
precise concentricity & tolerances.
Drawing

Similar to extrusion, except: pulling force is applied

stock (bar) die

wire

F (pulling force)

Commonly used to make wires from round bars

Metal Drawing
Wire Drawing
• Drawn wires→ is coiled round a power reel.

KMS2243 - Extrusion - MDAR

33
Wire Drawing
AUDI engine block
Wire Drawing
• Stock need to be prepared before wire could be drawn.
• Where, material should be ductile enough since it would be
pulled ( tensile forces).
• Annealed process→ providing necessary ductility to the
wire.’
• Pressure→ no force applied for pushing. But very high
pressure acting between the die & wire interface.
• Lubrication→ would be difficult and is mandatory (cause a
serious problems).
• Lubricating methods→ sulling, coppering, phosphating and
liming.
Wire Drawing
• The dies→ are severely affected due to ↑ stresses &
abrasion. Special materials of dies used for the process.
Such as, cast iron, alloy steels, tungsten carbide (long life),
diamond (fine wires) etc.

• Wire drawing improves the mechanical properties due to

the cold working.

• This process Is done in several passes as needed.

V6 engine block
BMW cylinder head
Brake assembly
Impellers
 Crank Shaft

Also see: http://auto.howstuffworks.com/engine7.htm

 MUHAMMAD ILHAM BIN KHALIT 6/11/2013

CASTING PROCESS

1
 MUHAMMAD ILHAM BIN KHALIT 6/11/2013

CASTING PROCESS
 The casting process basically involves :
(a) pouring molten metal into a mold patterned after the
part to be manufactured,
(b) allowing it to solidify, and
(c) removing the part from the mold.

 Important considerations in casting operations are as

follows:
a) Flow of the molten metal into the mold cavity
b) Solidification and cooling of the metal in the mold
c) Influence of the type of mold material

2
MUHAMMAD ILHAM BIN KHALIT 6/11/2013

3
Sand Casting
 MUHAMMAD ILHAM BIN KHALIT 6/11/2013

SAND CASTING PROCESS

5
 MUHAMMAD ILHAM BIN KHALIT 6/11/2013

CONTINUE..

6
 MUHAMMAD ILHAM BIN KHALIT 6/11/2013

CONTINUE..

7
 MUHAMMAD ILHAM BIN KHALIT 6/11/2013

CONTINUE..

8
 MUHAMMAD ILHAM BIN KHALIT 6/11/2013

SAND MOLD

9
 MUHAMMAD ILHAM BIN KHALIT 6/11/2013

SAND MOLD

10
 MUHAMMAD ILHAM BIN KHALIT 6/11/2013

TYPE OF SAND MOLD

 Sand molds are oven dried (baked) prior to

pouring the molten metal; they are stronger
than green-sand molds and impart better
dimensional accuracy and surface finish to the
casting.

11
 MUHAMMAD ILHAM BIN KHALIT 6/11/2013

PATTERN

 Patterns are used to mold the sand mixture

into the shape of the casting and may be made
of wood, plastic, or metal.
 The selection of a pattern material depends on
the size and shape of the casting, the
dimensional accuracy and the quantity of
castings required, and the molding process.

12
Shell mold casting
- metal, 2-piece pattern, 175C-370C
- coated with a lubricant (silicone)
- mixture of sand, thermoset resin/epoxy
- cure (baking)
- remove patterns, join half-shells  mold
- pour metal
- solidify (cooling)
- break shell  part
Investment casting (lost wax casting)

(b) Multiple patterns

(a) Wax pattern
assembled to wax
(injection molding)
sprue

(c) Shell built 

(d) dry ceramic immerse into ceramic
melt out the wax slurry
fire ceramic (burn wax)  immerse into fine sand
(few layers)

(e) Pour molten metal (gravity)

 cool, solidify (f) Break ceramic shell
[Hollow casting: (vibration or water
pouring excess metal before blasting)
solidification

(g) Cut off parts

(high-speed friction
saw)
 finishing (polish)
 Vacuum casting

Similar to investment casting, except: fill mold by reverse gravity

Easier to make hollow casting: early pour out

MUHAMMAD ILHAM BIN KHALIT 6/11/2013

16
Expendable Mold Casting

- Styrofoam pattern
- dipped in refractory slurry  dried
- sand (support)
- pour liquid metal
- foam evaporates, metal fills the shell
- cool, solidify
- break shell  part
 MUHAMMAD ILHAM BIN KHALIT 6/11/2013

SOLIDIFICATION TIME

n
 volume 
solidifica tiontime  C  
 surfacearea 

18
 MUHAMMAD ILHAM BIN KHALIT 6/11/2013

DESIGN GUIDELINES
1. Use of uniform thicknesses in a casting,
• Will lead to uniform cooling and solidification.
• Leads to stress free and distortion free castings.
• Heavier sections cool more slowly, and may have
shrinkage cavities, porosities and large grain
structures.
• Voids, porosities and cracks can be sites of
subsequent failures and should gestation be
prevented by minimizing variations in cross
sections.

19
 MUHAMMAD ILHAM BIN KHALIT 6/11/2013

CONTINUE

2. When uniform cross-sections cannot be

maintained, then changes in cross-sections
must be gradual.
• A recommended way to achieve this is to use a
transition radius of 1/3 of the thicker section
and blend in the radius with a 15-degree slope
line.

20
 MUHAMMAD ILHAM BIN KHALIT 6/11/2013

CONTINUE..

21
 MUHAMMAD ILHAM BIN KHALIT 6/11/2013

CONTINUE..

3. When two or more uniform sections intersect,

they create a region of heavy cross-section,
resulting in the problems mentioned earlier.
One way to minimize this is to core the
intersection by a hole, similar to a hub hole in
a wheel with spokes

22
 MUHAMMAD ILHAM BIN KHALIT 6/11/2013

CONTINUE..
 When sections intersect to form continuous ribs,
contraction occurs in opposite directions as the
material cools down. This leads to a high stress area
at the intersections, causing cracking immediately, or
in service. The way to avoid this is to stagger the ribs
and thereby maintain uniform cross-sections

23
 MUHAMMAD ILHAM BIN KHALIT 6/11/2013

CONTINUE..

4. Large unsupported areas tend to warp, so they

should be avoided.
5. In addition, a minimum wall thickness must be
maintained to avoid voids and non-fill areas.
See casting allowance table for minimum wall
thickness for some common metals.

24
 MUHAMMAD ILHAM BIN KHALIT 6/11/2013

SHRINKAGE

 Shrinkage, which causes dimensional changes

and (sometimes) cracking, is the result of the
following three sequential events:
1. Contraction of the molten metal as it cools prior
to its solidification.
2. Contraction of the metal during phase change
from liquid to solid (latent heat of fusion).
3. Contraction of the solidified metal (the casting)
as its temperature drops to ambient temperature.

25
 MUHAMMAD ILHAM BIN KHALIT 6/11/2013

DEFECT

 These defects occur because the casting cannot shrink freely during cooling,
owing to constraints in various portions of the molds and cores.(hot tear in
casting)

26
 MUHAMMAD ILHAM BIN KHALIT 6/11/2013

CONTINUE

 Common defect in casting. These defects can be minimized or

eliminated by proper design and preparation of molds and
control of pouring procedures.
27
 MUHAMMAD ILHAM BIN KHALIT 6/11/2013

POROSITY

 Porosity in a casting may be caused by

shrinkage, or gases, or both.
Figure shows the various
types of (a) internal and
(b) external chills (dark
areas at corners) used in
castings to eliminate
porosity caused by
shrinkage

28
COURSE INFORMATION
Name of Course/Module : Manufacturing process
Course Code : KMS 2243
Department : Mechanical
Name(s) of academic staff :
Credit Hours : 3 (3+0)T
Credit Value :
Contact hours: 3
Semester and Year offered : Semester 2 Year 2
Prerequisite (if any) : KMS 1133 - Material Science
Co-requisite (if any) :
This course is the core courses for those undertaking B.Eng. (Hons) Mechanical and a
Rationale for the inclusion of prerequisite for Machining and machine tool operations and CIM. The concepts and
the course/module in the techniques that are developed in this course will constitute a foundation for disciplines
programme : in materials engineering. By the end of programme, students will understanding the
basic concepts of metal forming, casting, metal cutting, joining and assembly process
This course will make students comprehend the various manufacturing process such as
metal forming, metal cutting processes, cutting operations, joining and assembly
Synopsis
process, mechanical assembly process like rivets, metal surfacing operation and
coating as well as deposition process.
At the end of this course students should be able to:

CLO 1: Identify the qualities of manufactured products such as mechanical

and physical properties, geometrics and forms.
CLO 2: Evaluate the properties and processing of different ferrous and non-ferrous
alloys.
CLO 3: Differentiate the various kind of fundamental casting processes and the
Course Learning outcomes defects from casting.
(CLO) :
CLO 4: Analyse basic mechanisms of bulk deformation processes and various
techniques of sheet metal working processes such as forging, extrusion, rolling and
drawing, cutting, bending and drawing.
CLO 5: Analyse metal removal processes such as machining and evaluate tool
life.
CLO 6: Define and classify various joining processes such as welding, brazing,
soldering and mechanical joining processes.
Transferable Skills This course is aimed to ensure students have knowledge on type of manufacturing
process which are essential for mechanical and Production engineer. This course will
also enhance students’ confidence to explain and develop their skills in process
selection based on production type.
Delivery and assessment
method : Delivery method Assessment

Lectures and tutorials Tests, examinations, quizzes,

individual assignment, exercises

Assessment Distribution
Type Assessment Number %Each %Total

Summative Final Examination 1 - 50

Test

Quizzes
Formative
Individual asignment 50

Attendance
 Overall Total 100

Attendance
The students should adhere to the rules of attendance as stated in the University
Academic Regulation:-
1. Student must attend not less than 80% of lecture hours as required for the subject
2. The student will be prohibited from attending any lecture and assessment activities
upon failure to comply the above requirement. Zero mark will be given to the subject.
DO ASK questions if you have difficulties but NEVER COPY! Please note PLAGIARISM
is a very serious offence
STUDENT LEARNING TIME
(SLT) No. Teaching and Learning Activities Student Learning Time
(Hours)

1. Lecture (L) 42

2. Face to face supervision a) Tutorial (T) -

3. Face to face supervision a) Laboratory (L) -

4. Face to face supervision a) Group Project (GP) -

5. Independent Study 89

Total 131

Main references supporting 1. Manufacturing Engineering and Technology 4TH Edition, S. Kalpakjian & S.R.
the course Schmid Prentice Hall, International Edition (2001)

Additional references 2. M. P. Groover, “Fundamentals of Modern Manufacturing 2/e” ©2002 John

supporting the course Wiley & Sons, Inc.
Content outline of the course/module and the SLT per topic

Week Course Contents Lecture(L) Tutorial(T) Lab(L)/Group Project(GP) Independent Study Student Learning Time (SLT)

W1 Chapter 1
 What is Manufacturing?
 Materials in Manufacturing 3 2 5
 Manufacturing Processes
 Production Systems
 Organization of the Book
Credit
W2 Chapter 2
3 4 7 Distributi
 Stress- Strain Relationships
ons:
 Visco-elastic Behavior of Polymers
W3 Chapter 3 3 8 11
 Dimensions, Tolerances,
W4 Chapter 4 3 5 8
 Alloys and Phase Diagrams
W5 Chapter 5 3 6 9
 Overview of Casting Technology
W6 Chapter 6 3 8 11
 Sand Casting
W7 Chapter 7 3 10 13
 Overview of Metal Forming
MID-TERM BREAK

W8 Chapter 8 6
3 3
 Bulk Deformation
W9 Chapter 9 8
3 5
 Sheet metal Working
W10 Chapter 10 12
3 9
 Metal Cutting Theory
W11 Chapter 11 8
3 5
 MACHINING OPERATIONS AND MACHINE TOOLS
W12 Chapter 12 3 11 14
 CUTTING TOOL TECHNOLOGY
W13 Chapter 13 13
3 10
 HEAT TREATMENT OF METALS
W14 Chapter 14 3 3 6
 Measurement & Inspection
Total of Student Learning Time (SLT) 42 89 131
 No. Teaching and Learning Activities Instruction Individual Learning Total Learning Credits
Hours Hours Hours
1. Lecture (L) 42 56 98 2.45

2. Final Exam - 15 15 0.375

3. Test - 6 6 0.15

4. Exercise - 1 1 0.025

5. Quiz - 3 3 0.075

6. Assignment - 10 10 0.25

Total 42 89 131 3.275

Mapping of the course/module to the Programme Aims

Programme Educational Objective

Course
PEO1 PEO2 PEO3 PEO4

KMS 2243   
Mapping of the Course Learning outcomes (CLOs) to the Taxonomy:

Taxonomy

Course Learning Outcomes Cognitive (C) Psychomotor Affective

At the end of this course students should be able to:
C1 C2 C3 C4 C5 C6 P1 P2 P3 P4 P5 P6 P7 A1 A2 A3 A4 A5

CLO 1: Identify the qualities of manufactured products such as mechanical 

and physical properties, geometrics and forms.
CLO 2: Evaluate the properties and processing of different ferrous and non-ferrous 
alloys.
CLO 3: Differentiate the various kind of fundamental casting processes and the 
defects from casting.
CLO 4: Analyse basic mechanisms of bulk deformation processes and various

techniques of sheet metal working processes such as forging, extrusion, rolling and
drawing, cutting, bending and drawing.
CLO 5: Analyse metal removal processes such as machining and evaluate tool 
life.
CLO 6: Define and classify various joining processes such as welding, brazing, 
soldering and mechanical joining processes.
Cognitive Psychomotor Affective
C1 – Knowledge P1 – Perception A1 – Receiving Phenomena
C2 – Comprehension P2 – Set A2 – Responding Phenomena
C3 – Application P3 – Guided Response A3 - Valuing
C4 – Analysis P4 – Mechanism A4 – Organizing Value
C5 – Synthesize P5 – Complex Overt response A5 – Internalizing Value
C6 – Evaluation P6 – Adaptation
P7 – Origination
Mapping of the Assessment Method to the Course Learning Outcomes (CLOs):

Course Learning Outcomes (CLOs)

Assessment Methods
CLO1 CLO2 CLO3 CLO4 CLO5 CLO6 CLO7 CLO8 CLO9 CLO10

Final Exam    

Test 1  

Test 2   

Quiz 1 

Quiz 2  

Assignment 1  

Assignment 2  
Mapping of the Course Learning Outcomes (CLOs) to the Programme Learning Outcomes (PLOs) :

Course Learning Outcomes PROGRAM LEARNING OUTCOMES

Delivery Assessment
At the end of this course students should be able to: KNOWLEDGE SKILLS ATTITUDE Methods Methods

B. Eng. (Hons.) Mechanical PLO1 PLO2 PLO3 PLO4 PLO5 PLO6 PLO7 PLO8 PLO9 PLO10 PLO11

CLO 1: Identify the qualities of manufactured products  Lecture  Test

1 1 1
such as mechanical and physical properties, geometrics  Assignment
and forms.  Final Exam
 Lecture  Quiz
CLO 2: Evaluate the properties and processing of different 3 3  Test
ferrous and non-ferrous alloys.  Assignment
 Final Exam
 Lecture  Quiz
CLO 3: Differentiate the various kind of fundamental 2 2 2  Test
casting processes and the defects from casting.  Assignment
 Final Exam
CLO 4: Analyse basic mechanisms of bulk deformation  Lecture  Test
processes and various techniques of sheet metal working  Assignment
processes such as forging, extrusion, rolling and drawing,
2 2  Final Exam
cutting, bending and drawing.

CLO 5: Analyse metal removal processes such as  Lecture 

machining and evaluate tool 2 2
life.

CLO 6: Define and classify various joining processes such  Lecture 

as welding, brazing, soldering and mechanical joining 1 1
processes.

RATING ON OBJECTIVE IN RELATIONS TO PROGRAM LEARNING OUTCOMES: 1 VERY SLIGHTLY 2 MODERATELY 3 SUBSTANTIV
Level/Domain Cognitive Psychomotor Affective
Basic (1) C1. Knowledge P1. Perception A1. Receiving Phenomena
C2. Comprehension P2. Set A2. Responding to Phenomena
Intermediate (2) C3. Application P3. Guided Responses A3. Valuing
C4. Analysis P4. Mechanism A4. Organizing Values
Advanced (3) C5. Synthesis P5. Complex Overt Response A5. Internalizing Values
C6. Evaluation P6. Adaptation
P7. Origination
NO. The faculty is committed to produce:

PEO 1 Employable graduates who can apply mechanical engineering knowledge in

practice.
PEO 2 Graduates with effective communication and leadership skills.
PEO 3 Graduates who are ethical, professional and environmentally conscious in their
practice.
PEO 4 Graduates with entrepreneurship skills and actively involved in life -long
learning for successful career advancement

Bachelor of Engineering

PLOs STATEMENT

At the end of the programme students should be able:

to apply knowledge of basic mathematics, science and engineering

PLO 1
fundamentals

PLO 2 to be proficient in core engineering discipline

PLO 3 to identify, analyze and solve engineering problems .

PLO 4 to apply industrial standards in the execution of engineering design

to conduct experiment, handle engineering tools as well as analyze and

PLO 5
interpret data necessary for engineering practices

PLO 6 to communicate effectively in written and oral form

PLO 7 to function effectively in a team as a member or a leader

to demonstrate entrepreneurship and project management skills to meet

PLO 8
economic challenges.

to describe the benefits of engineering activities on environment, safety and

PLO 9
society in support of sustainable development

PLO 10 to demonstrate professional and ethical in their profession

PLO 11 to recognize and possess the capability to embark on lifelong learning

Example 10.1(refer page 248)

Assume n=2

The volume of the piece is taken as unity.

1
Thus, solidification time=
( surfaceare) 2

The respective surface areas are as follows:

Sphere:

1
4 3 3
V= r 3 , r= ( )
3 4
2
3
A= 4r  4 ( ) 3  4.84
2

4

Cube:

3
V= a a=1

A= 6a  6
2

Cylinder:

1
 1 3
V= r h  2r r=  
2 3

 2 
2
 1 3
A= 2r  2rh  6r  6 
2 2
  5.54
 2 

The respective solidification times are therefore:

T sphere=0.043C fastest=cube slowest=sphere.

Tcube=0.028C

T cylinder=0.033C
 MUHAMMAD ILHAM BIN KHALIT 30/10/2013

STRESS-STRAIN

FUNDAMENTAL PROPERTIES OF
MATERIALS
1
 MUHAMMAD ILHAM BIN KHALIT 30/10/2013

INTRODUCTION

 In manufacturing operations, numerous parts

and components are formed into various
shapes by applying external forces to the
workpiece, typically by means of various tools
and dies.
 There are variety of metallic and nonmetallic
materials and have an equally wide range of
properties, as shown qualitatively in Table 2.1

2
 MUHAMMAD ILHAM BIN KHALIT 30/10/2013

TENSILE STRAIN

 geometrical measure of deformation between

particles in a material body
 STRAIN=EXTENSION/ORIGINAL LENGTH
Initial length=75mm
APPLY
TENSILE (100 - 75) mm 25mm
LOADING. strain  
75 mm 75mm
Final length=100mm Strain=0.33

This sometimes expressed as

strain of 33%

3
 MUHAMMAD ILHAM BIN KHALIT 30/10/2013

STRESS

 Define as force applied to target area

force
stress 
area F = stress x A

109 N 1m 2
F 2
2
x0.01mm x
m 1x108 mm 2
F = 10 N

4
 MUHAMMAD ILHAM BIN KHALIT 30/10/2013

FIND DIAMETER
force
stress 
area
force
area 
stress
15 kN
area 
75 MN m – 2
Area = 2 x 10–4 m2

d 2
A
4
4 xA 4  2  104 m2
d d
 3.14

d = 1.6 x 10–2 m

5
 MUHAMMAD ILHAM BIN KHALIT 30/10/2013

CABLE EXTENSION
 A large crane has a lifting cable of :
 Diameter=36mm
 Young modulus= 200Gpa
 This crane is used to lift 20kN,the unstretched cable is
25m.calculate the extension cable.
d 2 3.14  (3.6  10 2 m) 2 =1.02 x 10–3 m2
A 
4 4

F A
E 
l l

F l 20  10 N  25 m
3
l   = 2.5 x 10–3 m or 2.5 mm
A  E 1.02  10 – 3 m 2  2  1011 N m – 2