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MKM1233
ADVANCED MANUFACTURING

By: Dr. Siti Rabiatull Aisha Idris

Email: rabiatull@ump.edu.my
Contact: +6094246349
Office:

Assessment
This assessment only valid for half semester (from week 1 to 7), the rest will be
taken over by other lecturer:
Topics/ Chapters
Test 1 (2hrs)

Chapter 1-3

Date
3rd

October 2013

Venue
In
Class

Assignments*
Project
Report and
Presentation

15 %
15 %

Progress presentation: 26th

Case study basis must

cover Chapter 1-6
September 2013
(format can be
downloaded from
www.edmodo.com)

Final Exam

Marks

Chapter 5-6

Final presentation and

In
report submission: 22nd
Class
September 2013 (8.30pm)softcopy and hardcopy

7.5 %
(5.5%
report+2%p
resentatn)

20 %

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Group Assignments*:
Group

Topics

Date of Presentation and Submission

Metal Forming Process:

- Details of high energy rate forming (HERF) process, Electromagnetic forming, Explosive forming, Stretch forming,
Contour roll forming

Present: 26th September 2013

Submission: 3rd October 2013

Modern CNC Technology:

- NC system, Interpreter and Interpolator, Acceleration and
Deceleration, PID control system, Numerical Control Kernel,
Man-Machine Interface, CNC architecture design

Present and submit: 10th October 2013

Reverse Engineering:
- Digitizing, laser scanning, CT-scanning, point cloud
manipulation, Data segmentation, surface reconstruction,
model further processing

Present and submit: 17th October 2013

Spline-based & Subdivision-based Approaches for Reverse

Engineering:
- Various approaches for sample data parameterization,
Various approaches for knots allocation, Splice surface
fitting, Topological modeling through mesh simplification,
Direct subdivision surface fitting, Parameterization-based
subdivision surface fitting

Present and submit: 17th October 2013

**Must be submitted in softcopy and hardcopy

CONTENT

Chapter
Chapter
Chapter
Chapter
Chapter
Chapter

1: Advanced Machining Processes: Non-conventional machining process

2: Advanced Metal Casting
3: Advanced Metal Forming Processes
4: Modern CNC Technology
5: Reverse Engineering
6: Spline-based & Subdivision-based approaches for Reverse Engineering

Learning Objectives
By the end of semester, students should be able to:
LO1: Describe fundamentals of non-conventional (advanced) machining, advanced metal casting, &
advanced metal forming processes and their working principles.
LO2: Explain and summarize the knowledge, working principles, and design methods of modern CNC
systems.
LO3: Formulate and solve typical problems on reverse engineering for surface reconstruction from
prototype models through digitizing and spline based surfaces fitting
LO4: Describe and summarize various CAD issues for Rapid Prototyping; the principles of and key
characteristics of RP technologies; and typical rapid tooling processes for quick batch production.

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Chapter 1: Advanced Machining Processes:

Non-conventional machining process
a) Ultrasonic Machining (USM),
b) Jet Machining (AJM),
c) Electro- chemical Machining (ECM), Electro Discharge Machining (EDM), and
Electron Beam Machining (EBM),
d) Laser Beam Machining (LBM).

NON-TRADITIONAL PROCESSES
Traditional vs. non-traditional processes
A machining process is called non-traditional if its material removal mechanism is
basically different than those in the traditional processes, i.e. a different form of
energy (other than the excessive forces exercised by a tool, which is in physical contact
with the workpiece) is applied to remove the excess material from the work surface,
or to separate the workpiece into smaller parts.

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The principal characteristics of traditional machining processes

and non-traditional processes is presented to compare their
advantages and limitations:
Traditional Process

Non-traditional Process

The cutting tool and workpiece are always in physical

contact, with a relative motion against each other,
which results in friction and a significant tool wear.

there is no physical contact between the tool and

workpiece. Although in some non-traditional
processes tool wear exists, it rarely is a significant
problem;

Material removal rate of the traditional processes is

limited by the mechanical properties of the work
material.

Non-traditional processes easily deal with such

difficult-to-cut materials like ceramics and ceramic
based tool materials, fiber reinforced materials,
carbides, titanium-based alloys;

the relative motion between the tool and workpiece is

typically rotary or reciprocating. Thus, the shape of
the work surfaces is limited to circular or flat shapes.
In spite of widely used CNC systems, machining of
three-dimensional surfaces is still a difficult task.

Most non-traditional processes were develop just to

solve this problem;

Machining of small cavities, slits, blind or through

holes is difficult with traditional processes,

whereas it is a simple work for some non-traditional

processes;

well established, use relatively simple and inexpensive

machinery and readily available cutting tools.

require expensive equipment and tooling as well as

skilled labor, which increases significantly the
production cost;

From the advantages & limitations mentioned, it follows that non-traditional processes generally should be
employed when:

there is a need to process some newly developed difficult-to-cut materials, machining of which is
accompanied by excessive cutting forces and tool wear;

there is a need for unusual and complex shapes, which cannot easily be machined or cannot at all be
machined by traditional processes
The non-traditional processes are often classified according to the principle form of energy used:

mechanical processes: the mechanical energy differs from the action of the conventional cutting tool.
Examples include ultrasonic machining and jet machining;

electrochemical processes: based on electrochemical energy to remove the material. Examples include
electrochemical machining, and electrochemical deburring and grinding;

thermal energy processes: use thermal energy generated by the conversion of electrical energy to shape
or cut the workpiece. Examples include electric discharge processes, electron beam machining, laser beam
machining, and plasma arc cutting;

chemical machining: chemicals selectively remove material from portions of the workpiece, while other
portions of the surface are mask protected.

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a) Ultrasonic Machining (USM)

Ultrasonic Machining is a non-traditional process, in which abrasives contained in a slurry are driven against
the work by a tool oscillating at low amplitude (25-100 m) and high frequency (15-30 KHz)

Schematic of ultrasonic machine tool

The process was first developed in 1950s and was originally used for finishing EDM surfaces.
The basic process is that a ductile and tough tool pushed against the work with a constant force. A
constant stream of abrasive slurry passes between the tool and the work (gap is 25-40 m) to provide
abrasives and carry away chips. The majority of the cutting action comes from an ultrasonic (cyclic) force
applied.

a) Ultrasonic Machining (USM)-cont

The basic components to the cutting action are believed to be:
brittle fracture caused by impact of abrasive grains due to the tool vibration;
cavitation induced erosion;
chemical erosion caused by slurry.
Advantages

Disadvantages

Can be used to cut through and blind holes of round

or ..irregular cross-sections.

There is a little production of heat and stress in the

process, but work may chip at exit side of the hole.

The process is best suited to poorly conducting, hard

and brittle materials like glass, ceramics, carbides,
and semiconductors.

Sometimes glass is used on the backside for brittle

materials (for safety protection)
The critical parameters to control the process are the
tool frequency, amplitude and material, abrasive grit
size and material, feed force, slurry concentration
and viscosity

Limitations of the ultrasonic machining include very low material removal rate (MRR), extensive
tool wear, small depth of holes and cavities.

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a) Ultrasonic Machining (USM)-cont

Basic machine layout is shown in the figure below:

Principal components of an ultrasonic machine.

The acoustic head is the most complicated part of the machine. It must provide a static constant
force, as well as the high frequency vibration.
Tools are produced of tough but ductile metals such as soft steel of stainless steel. Aluminum and
brass tools wear near 5 to 10 times faster.
Abrasive slurry consists of a mixture of liquid (water is the most common but oils or glycerol are
also used) and 20% to 60% of abrasives with typical grit sizes of 100 to 800. The common types of
abrasive materials are boron carbide, silicon carbide, diamond, and corundum (Al2O3).

Chapter 1: Advanced Machining Processes:

Non-conventional machining process
a) Ultrasonic Machining (USM),
b) Jet Machining (JM),
c) Electro- chemical Machining (ECM), Electro Discharge Machining (EDM), and
Electron Beam Machining (EBM),
d) Laser Beam Machining (LBM).

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b) Jet Machining (JM)

In jet machining, high-velocity stream of water (Water Jet Cutting) or water
mixed with abrasive materials (Abrasive Water Jet Cutting) is directed to the
workpiece to cut the material. If a mixture of gas and abrasive particles is
used, process is referred to as Abrasive Jet Machining and is used not to cut
the work but for finishing operations like deburring, cleaning, polishing.
In this subtopic, we are going to cover:
i. Water Jet Cutting (WJC)
ii. Abrasive Water Jet Cutting (AWJC), and
iii. Abrasive Jet Machining (AJM)

Click ME!!!

b) Jet Machining (JM)

i. Water Jet Cutting (WJC)
Water Jet Cutting (WJC) uses a fine, high-pressure, high velocity (faster than
speed of sound) stream of water directed at the work surface to cause
slotting of the material.

Water Jet Cutting.

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b) Jet Machining (JM)

i. Water Jet Cutting (WJC)-cont
Water is the most common fluid used, but additives such as alcohols, oil
products and glycerol are added when they can be dissolved in water to
improve the fluid characteristics. The fluid is pressurized at 150-1000 MPa to
produce jet velocities of 540-1400 m/s. The fluid flow rate is typically from 0.5
to 2.5 l/min. The jet have a well behaved central region surrounded by a fine
mist. The form of the exit jet is illustrated in the figure below;

The jet structure in Water Jet Cutting.

b) Jet Machining (JM)

i. Water Jet Cutting (WJC)-cont
Typical work materials involve soft metals, paper, cloth, wood, leather, rubber, plastics,
and frozen food. If the work material is brittle it will fracture, if it is ductile, it will cut
well:

Water Jet Cutting of ductile material (Left) and brittle materials (Right).

The typical nozzle head is shown below. The orifice is often made of sapphire and its
diameter ranges from 1.2 mm to 0.5 mm:

The principle components of a nozzle head in Water Jet Cutting.

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b) Jet Machining (JM)

ii. Abrasive Water Jet Cutting (AWJC)
In Abrasive Water Jet Cutting, a narrow, focused, water jet is mixed with
abrasive particles. This jet is sprayed with very high pressures resulting in high
velocities that cut through all materials. The presence of abrasive particles in
the water jet reduces cutting forces and enables cutting of thick and hard
materials (steel plates over 80-mm thick can be cut). The velocity of the
stream is up to 90 m/s, about 2.5 times the speed of sound.

Abrasive Jet Cutter

b) Jet Machining (JM)

ii. Abrasive Water Jet Cutting (AWJC)-cont
Abrasive Water Jet Cutting process was developed in 1960s to
cut materials that cannot stand high temperatures for stress
distortion or metallurgical reasons such as wood and
composites, and traditionally difficult-to-cut materials, e.g.
ceramics, glass, stones, titanium alloys.
The common types of abrasive materials used are quarz sand,
silicon carbide, and corundum (Al2O3), at grit sizes ranging
between 60 and 120.
Click ME!!!

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b) Jet Machining (JM)

iii. Abrasive Jet Cutting (AJM)
In Abrasive Jet Machining, fine abrasive particles (typically ~0.025mm) are
accelerated in a gas stream (commonly air) towards the work surface. As the
particles impact the work surface, they cause small fractures, and the gas
stream carries both the abrasive particles and the fractured (wear) particles
away.

Click ME!!!
Abrasive Jet Machining.

b) Jet Machining (JM)

iii. Abrasive Jet Cutting (AJM)-cont
The jet velocity is in the range of 150-300 m/s and pressure is from two to
ten times atmospheric pressure.
The preferred abrasive materials involve aluminum oxide (corundum) and
silicon carbide at small grit sizes. The grains should have sharp edges and
should not be reused as the sharp edges are worn down and smaller
particles can clog nozzle.
Applications: deburring, etching, and cleaning of hard and brittle metals,
alloys, and nonmetallic materials (e.g., germanium, silicon, glass, ceramics,
and mica).

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Chapter 1: Advanced Machining Processes:

Non-conventional machining process
a)
b)
c)
d)

Ultrasonic Machining (USM),

Jet Machining (JM),
Electro- chemical Machining (ECM), and Electron Beam Machining (EBM),
Laser Beam Machining (LBM), Electro Discharge Machining (EDM).

c) Electric Discharge Machining (EDM)

In electric discharge processes, the work material is removed by a series of
sparks that cause localized melting and evaporation of the material on the
work surface.
The two main processes in this category that will be covered are
i.
electric discharge machining (EDM), and
ii. wire electric discharge machining (WEDM)
These processes can be used only on electrically conducting work materials.

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c) Electric Discharge Machining

i. electric discharge machining (EDM)
Electric discharge machining (EDM) is one
of the most widely used nontraditional
processes. An EDM setup and a close-up
view of the gap between the tool and the work
are illustrated in the figure:

The setup of Electric Discharge Machining (EDM) process

and close-up view of gap, showing discharge and metal
removal.

c) Electric Discharge Machining (EDM)

i. electric discharge machining (EDM)-cont
Process: A formed electrode tool produces the shape of the finished work
surface. The sparks occur across a small gap between tool and work
surface. The EDM process must take place in the presence of a dielectric
fluid, which creates a path for each discharge as the fluid becomes ionized
in the gap. The fluid, quite often kerosene-based oil is also used to carry
away debris. The discharges are generated by a pulsating direct-current
power supply connected to the work and the tool.
Electrode materials are high temperature, but easy to machine, thus
allowing easy manufacture of complex shapes. Typical electrode materials
include copper, tungsten, and graphite.
The process is based on melting temperature, not hardness, so some very
hard materials can be machined this way.
Click ME!!!

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c) Electric Discharge Machining (EDM)

ii. wire electric discharge machining (WEDM)
Wire Electric Discharge Machining (Wire EDM) is a special form of EDM that
uses a small diameter wire as the electrode to cut a narrow kerf in the work.
Wire EDM is illustrated in the figure:

The setup of Wire Electric Discharge

Machining (WEDM) process.

WEDM Machine.

c) Electric Discharge Machining (EDM)

ii. wire electric discharge machining (WEDM)-cont

The workpiece is fed continuously and slowly past the wire in order to achieve the desired cutting
path. Numerical control is used to control the work-part motions during cutting. As it cuts, the wire
is continuously advanced between a supply spool and a take-up spool to present a fresh electrode
of constant diameter to the work. This helps to maintain a constant kerf width during cutting. As in
EDM, wire EDM must be carried out in the presence of a dielectric. This is applied by nozzles
directed at the tool-work interface as in the figure, or the workpart is submerged in a dielectric
bath.
Wire diameters range from 0.08 to 0.30 mm, depending on required kerf width. Materials used for
the wire include brass, copper, tungsten, and molybdenum. Dielectric fluids include deionized
water or oil. As in EDM, an overcut in the range from 0.02 to 0.05 mm exists in wire EDM that
makes the kerf larger than the wire diameter.
This process is well suited to production of dies for sheet metalworking, cams, etc. Since the kerf is
so narrow, it is often possible to fabricate punch and die in a single cut, as illustrated in the figure:

Click ME!!!

Punch and die fabricated in a single cut by WEDM.

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Chapter 1: Advanced Machining Processes:

Non-conventional machining process
a)
b)
c)
d)

Ultrasonic Machining (USM),

Jet Machining (JM),
Electro Discharge Machining (EDM) and Electro- chemical Machining (ECM),
Laser Beam Machining (LBM), Electron Beam Machining (EBM).

d) Laser and Other Beams

In this subtopic, we are going to discussed only

on:
i. Laser beam machining (LBM), and
ii. Electron beam machining (EBM)

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d) Laser and Other Beams

i. Laser beam machining (LBM)
Laser beam machining (LBM) uses the light energy from a laser to remove
material by vaporization and ablation. The setup for LBM is illustrated in the
figure:

The setup of laser beam machining process.

d) Laser and Other Beams

i. Laser beam machining (LBM)-cont

The types of lasers used in LBM are basically the carbon dioxide (CO2) gas lasers.
Lasers produce collimated monochromatic light with constant wavelength. In the
laser beam, all of the light rays are parallel, which allows the light not to diffuse
quickly like normal light. The light produced by the laser has significantly less
power than a normal white light, but it can be highly focused, thus delivering a
significantly higher light intensity and respectively temperature in a very localized
area.
Lasers are being used for a variety of industrial applications, including heat
treatment, welding, and measurement, as well as a number of cutting operations
such as drilling, slitting, slotting, and marking operations. Drilling small-diameter
holes is possible, down to 0.025 mm. For larger holes, the laser beam is controlled
to cut the outline of the hole.
The range of work materials that can be machined by LBM is virtually unlimited
including metals with high hardness and strength, soft metals, ceramics, glass,
plastics, rubber, cloth, and wood.
LBM can be used for 2D or 3D workspace. The LBM machines typically have a laser
mounted, and the beam is directed to the end of the arm using mirrors. Mirrors
are often cooled (water is common) because of high laser powers.
Click ME!!!

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d) Laser and Other Beams

ii. Electron beam machining (EBM)
Electron beam machining (EBM) is one of several industrial processes that use
electron beams. Electron beam machining uses a high-velocity stream of
electrons focused on the workpiece surface to remove material by melting
and vaporization. A schematic of the EBM process is illustrated in the figure:

The setup of electron beam machining process.

d) Laser and Other Beams

ii. Electron beam machining (EBM)-cont

An electron beam gun generates a continuous stream of electrons that are focused
through an electromagnetic lens on the work surface. The electrons are
accelerated with voltages of approx. 150,000 V to create velocities over 200,000
km/s. The lens is capable of reducing the area of the beam to a diameter as small
as 0.025 mm. On impinging the surface, the kinetic energy of the electrons is
converted into thermal energy of extremely high density, which vaporizes the
material in a very localized area. EBM must be carried out in a vacuum chamber to
eliminate collision of the electrons with gas molecules.

Electron beam machining is used for a variety of high-precision cutting applications

on any known material. Applications include drilling of extremely small diameter
holes, down to 0.05 mm diameter, drilling of holes with very high depth-todiameter ratios, more than 100:1, and cutting of slots that are only about 0.025
mm wide. Besides machining, other applications of the technology include heat
treating and welding.

The process is generally limited to thin parts in the range from 0.2 to 6 mm thick.
Other limitations of EBM are the need to perform the process in a vacuum, the
high energy required, and the expensive equipment.

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Assignment: List down all the advantages,

disadvantages as well as limitation for each
processes

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