The document discusses the manufacturing processes for a disc brake part. It begins by introducing the group members and their task to identify the material and processes for an engineered part they selected, which was a disc brake. It then provides details on the specific processes and material used to produce a disc brake part, including: 1) Disc brakes are typically made of gray cast iron due to its properties like thermal stability and cost effectiveness. 2) The production process for a ceramic composite disc brake involves steps like pouring carbon fiber into a mold and pressing the ceramic material into a die. 3) Essential properties like dimensional accuracy, surface finish, and weight distribution are considered to ensure proper performance. 4) Disc

1. Abstract
At the beginning of this assignment, a group of 5 members is formed in order to discuss and
complete the report regarding the manufacturing cycles or processes involve in making the
desired part. But before we start our project, we were told to find and pick an engineered part
which later on, we have been given a task to identify the material and all the processes involve in
making that one particular engineered part that we choose. As for our part, we choose a disc
brake since it is most commonly used nowadays as a safety measure either to slows down or stop
a vehicle from or during moving. After we decided on picking a disc brake as our product, we
had a discussion on separating or distributing the questions among 5 members of the group. All
the questions from 1(a) to 1(d) were answered and compiled into one document or report. As to
end this report, a conclusion is made based on the overall report.
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2. Contents
Abstract I
Introduction 1
Findings and discussions
(a) The type of materials used to produce the parts 2
(b) The process employed in producing the final part 3 - 4
(c) The considered essential process responses of the part 5
(d) Whether the part was processed using conventional or AMP 6 - 7
Conclusion 8
References II

3. Introduction
Traditional manufacturing processes and advanced manufacturing processes are both in
use at today’s industries. Both of these categories of processes may involve different
mechanisms or methods to produce the same product and thus will results in parts with different
mechanical properties and shape. Usually the part that machined through an advanced
manufacturing process will results in more ideal surface finish and dimensional accuracy
compared to the traditional manufacturing processes. This is because, in unconventional
manufacturing processes, both tool and the work piece won’t make any contact and thus leads to
minimum probability of having defects and any other undesirable effects on the product. Most of
the non – traditional manufacturing processes will also produce a part with small heat affected
zone and machined to get cleaned edges with less burrs. But still, some industries are motivated
to use traditional manufacturing processes because of the production cost which usually lower
than the advanced manufacturing processes and it is simple to handle the machine since these
machines only require low- moderate skills. Since as the world keeps growing, vehicles like cars,
motorcycle and buses have been use as the mean of transportation to reach a certain destination.
So, the safety of these user or driver of the vehicles must be prioritized. The safety of these
vehicles are always researched and developed. One of the developments that have been made is
the braking system which usually involves a disc brake and few other brake parts. A disc brake is
type of brake that uses calipers to squeeze pairs of pads against a disc in order to create friction
that retards the rotation of a shaft, such as a vehicle axle, either to reduce its rotational speed or
to hold it stationary. A disc brake may formed or made of either gray cast iron or ceramic
composite but still both of these material will produce a disc brake with the same reason which is
to reduce or stop the motion acts on any vehicle. Ever since it was introduced, the braking
system was keep developed and improved to ensure the safety of the consumers. Furthermore,
the braking disc have its own advantage as it makes the driver to feel the changes of speed from
their own braking, proportional to the pressure placed on the brake pad. So to proceed with this
assignment, we choose a disc brake as the part to be discussed throughout the report.
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4. Gray cast iron disc brake

5. Findings and Discussions
Section A
(a) The type of materials used to produce the parts
A disc brake is a type of brake that uses calipers to squeeze pairs of pads against a disc either to
reduce its rotational speed or to hold it stationary. Since disc brake is a crucial component from
safety point of view, materials used for brake system should be stable frictional and wear in
every condition.
The disc brake (or rotor in American English) is traditionally made of cast iron. Cast iron contain
more than 2% dissolved carbon within its matrix (as opposed to steel which contains less than
2%). The alloy constitution affect its colour when fractured, white cast iron has carbide
impurities which allows cracks to pass straight through. Grey cast iron has graphite flakes which
deflect a passing crack. Ductile cast iron which stops the crack from further progressing due to
their spherical graphite “nodules”.
Considering its cost , relative ease of manufacture and thermal stability, this cast iron
(particularly, grey cast iron where the stiffness of the component is more important than its
tensile strength) is actually a more specialized material for brakes applications particularly the
material of choice for almost all automotive brake disc. Cast iron tends to be brittle, except for
malleable cast iron. With its relatively low melting point, good fluidity, castability (which is the
ease of forming a quality casting, making producing a disk brake with minimal tooling cost,
energy and rejections), excellent machinability (making the disk brake removal of material with
a satisfactory finish at low cost), resistance to deformation and wear resistance.
In most vehicles, the brake disc are made of cast iron, but in certain other cases such as high
performance vehicles these brake disc are not up to their standards because the cast iron brake
disc are heavy and it reduces the vehicle’s performance, so a ceramic composite brake disc are
used. The manufacturing uses the short carbon fiber, carbon powder and heat molded resin.
When the disk shape is obtained by heating the mixture and cooling down, another ceramic
material know as silicon is added to harden the brake disk. The ceramic composite brakes is
lightweight and also heat resistant and can last 60 times longer than regular cast iron brake disc
which makes it more expensive compared to the cast iron.
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6. Section A
(b) The process employed in producing the final part.
Steps in producing the final part of ceramic composite disc brake
1. Pouringof carbon fiberintothe mould. 2. Aluminiumcore insertion.
3. Fillingandlavelingof ceramicinthe die 4. Pressingof ceramicmaterial inthe die
5. Mould enteringlarge pressfortreatment 6. Formationof plasticintocarbon
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7. 7. Crucible fordischeatingwithsilicon 8. Pouringof siliconpowder
9. Machiningof disc 10. A finishedcomposite discbrake
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8. Section A
(c) The considered essential process responses of the part
Usually a computer guided machine which produces high definition photographs is used to
examine the quality of the disc brake by looking into the microstructures of the discs. This
process is controlled carefully so that it will form the proper microstructure resulting in a part
with the correct tensile strength, hardness and microstructure. If the part is made of gray irons,
the grain structure would be pearlitic. If a disc brake that is too hard may crack while one that is
too soft may wear prematurely. These brake discs manufactured from the gray iron, will not
subject to wear and they are also heat and rust resistant during day to day use. These disc brakes
also ensure very high consistent frictional values throughout the deceleration process of a
vehicle.
Since we are using a traditional method to produce the part, the formation of the shrinkage of
porosity of a product should be reconsidered because it might decrease the performance of the
disc brake. The dimensional accuracy of the part might not be very precise but it can be
machined in the range of the tolerances. Meanwhile, the surface finish on the part also important
because it affects the friction characteristics of the brakes, pad seating, break-in, wear and noise.
The surface roughness of the disc brake would be around 0.8 Ra. Moreover, the shape of the disc
brake does not influence the performance so the shape can be varies from one industry to
another. But the weight of the part plays an important role, higher the thickness or weight, faster
the heating rate or slower the cooling rate of the disc. A good quality of disc brake should have
more mass (weight) so that it will heat up slower and more surface area to help the disc cool
faster. Besides, all the holes on the disc brakes were designed to decrease the weight of the disc
brake and also to increase the surface area. Note that all holes or the design are symmetrical at
both side so that the weight of the disc brake would be balanced and by doing so we can reduce
the vibration acts on it.
Compared to gray irons, disc brakes that made from ceramic composite materials are lighter and
it does not wear off as quickly as gray irons. Ceramic discs are used in some high-performance
cars and heavy vehicles. Not only that we can reduce the weight by using ceramic composites, it
is also provides stable friction from very high speeds and all temperatures. Due to the high heat
tolerance and mechanical strength of ceramic composite discs, they are often used on exotic
vehicles where the cost is not prohibitive to the application. They are also found in industrial
applications where the ceramic disc's light weight and low-maintenance properties justify the
cost relative to alternatives. Composite brakes can withstand temperatures that would make steel
discs bendable.
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9. Section A
(d) Whether the part was processed using conventional or AMP
To process a brake disc or rotor we can use both conventional and unconventional processes. But
each process produces a product with different dimensional accuracy at different period of time
and cost. As in question B, the part was made using a traditional method which is involving the
uses of casting and turning.
When comes to traditional manufacturing processes, we can use either metal casting or metal
forming to produce a disc brake with a particular shape. For these types of processes we need
dies that have shapes of the desired product. Moreover, the part produced at the end of these
processes will be needed to go through the secondary process which involves the removal of
extra metal according to the desired dimensional accuracy, hence the part is machined to get a
better surface finish and thus require more time and cost. Furthermore, sometimes defects or heat
affected zone may formed during these conventional processes especially during machining
which may undesirable for the part. For example like, the inner core of the disc brake becomes
too hard which is harder than it was supposed to be (or too soft, depends on the type of material),
due to the heat affected zone and thus may leads to the failure of the part when in use.
Meanwhile, as for advanced manufacturing processes we can use either water jet and abrasive
water jet machining or laser beam machining in order to get a very precise dimensional accuracy.
At most of times cast iron was used as a raw material in the brake disc manufacturing processes,
and there’s many types of cast iron like gray iron, ductile iron, compacted graphite iron,
austempered ductile iron and high alloy or white iron. Every type and grade of cast iron is
unique, machining cast iron components depends upon the material’s graphite structure,
microstructure of the metal matrix, temperature-to-time history of the castings and the
distribution of C that remains in the metal matrix. But usually in this industry we use gray iron.
Since, gray iron has excellent machinability with superior wear resistance characteristics,
damping capability and a very good electrical conductor, we also can use electrical discharge
machining (EDM) or chemical (CM) and electrochemical machining (ECM) to process the disc
brake. Unfortunately we can’t use EDM for ceramic composites because they do not conduct
electricity. Hence no sparks will be produced to shape the ceramic composites into the desired
shape and dimensions of disc brakes, unless it is coated with a good electrical conductor.
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10. In traditional manufacturing processes, since the machining processes involve physical contact
between a work piece and the tool, few defects may be formed. When machining cast irons, the
most common problems are flank wear, crater wear, notch wear and built-up-edge which caused
by abrasion, adhesion and diffusion. Thus, the basic requirements for the cutting tool material for
machining cast iron are: it is must resistance to adhesive and abrasive wear caused by the
variable microstructures; it must have sufficient toughness for the material to be machined; and
the capability to machine at high speeds and feed rates.
Since a disc brake is a very crucial part of a transport or automation and to ensure the safety of
consumers, it is recommended that the parts should be processed using advanced manufacturing
processes. This is because not only that by doing so, we can increase the production of exact
desired part with the desired dimensional accuracy by reducing the defects and errors, we also
can gain our clients trust and thus may increase the profit and spread out the business. Moreover,
most of the advanced manufacturing processes involve no contact between tool and a work piece
and thus may reduce few defects. Furthermore, processing a disc brake using advanced
manufacturing processes also can produce a part with the desired hardness which not affected or
changed by the heat affected zone, and thus may prevent the disc brake from getting cracks due
to unplanned impacts especially when the brake discs were too hard.
Of all advanced manufacturing processes, water jet cutting is the most suitable process to be used
in manufacturing of brake discs. Water jet cutting is a cutting process when a small (0.3 mm) jet
of water and abrasive (12-15%) is fired at high velocities (1000 m/s) into a material which then
result in a very smooth clean cut at relatively fast rates. In short, water jet cutting is a cutting
process which uses a high pressure stream of water. Sometimes it is also used for cleaning
purposes. Unlike laser or thermal cutting, water jet can cut almost any type of materials like
ceramics and cast irons which sensitive to extreme temperature and may damage due to the
temperature. Since the product that we have chosen is simple and made of a flat cast iron (gray
iron), it is easier to produce a disc brakes out of it by water jet cutting which is simply only
involves cutting the material precisely according to the pattern provided. Moreover, the
production cost for using water jet is lower than most advanced manufacturing processes because
it is only use water (sometimes with abrasives that harder than work piece) and these water used
can be recycled to be used again (infinite water supply). Compared to any other traditional
processes, the processing time can be reduced by eliminating or reducing expensive secondary
processes. Since no heat is applied to the material, cut edges are clean with minimal burr. By
using this process, we can get a product with minimal heat affected zone because the water
involved will eventually cool down the work piece (the disc brake) as it cut.
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11. CONCLUSION
Both conventional and unconventional processes are used on daily basis and each of
these processes has its own advantages and disadvantages in form of production cost and
duration. Moreover, different categories of manufacturing processes will also produce parts with
different responses regarding its dimensional accuracy, surface finish, hardness or grain structure
of the material. Disc brake is one of the products that can be produced using these processes,
both traditional and advanced manufacturing processes. But different use of process will results
in different aspects and impacts on the production of the disc brake and characteristics of the part
itself. Disc brake is a type of brake that uses calipers to squeeze a pairs of pads against a disc in
order to create friction that retards the rotation of a shaft, such as a vehicle axle, either to reduce
its rotational speed or to hold it stationary (stop movement). Brake discs are widely used or
applied especially on modern vehicles like cars, motorcycles and bicycles. These disc brakes can
be either made from cast iron which usually involves the gray cast iron or ceramic composite.
Ceramic composite disc brake are usually used in some high-performance cars and heavy
vehicles, and it is slightly superior to the gray cast iron especially when involve the weight and
other mechanical properties. Out of all processes that can be used to manufacture disc brake,
water jet cutting is the most favorable. This is because this process unlike any other processes,
involves unlimited source of water and some abrasives like sands, and thus leads to low
production cost and the part itself can be produced at faster rates. Water jet cutting is an
advanced process that uses a high pressure stream of water to cut or clean a product. In water jet
cutting, all the edges will be cut precisely according to the desired shape or pattern, leaving clean
edges with minimal burrs and the water itself will act like a coolant which will reduce the heat
affected zone. Since the dimensional accuracy of the part produced is precise, the expensive
secondary processes can be eliminated. Hence, the part produces is more ideal and identical to
our desired shapes and other parts’ characteristics. Of all of the considerations, the most
important point was the proper hardness of the disc brake. If the disc brake was too hard, it will
eventually fail or crack when exposed to extreme conditions or high impacts. Meanwhile, if the
brake disc was too soft, it will wear off quickly. Long story short, the safety of the consumer
should be considered because of these circumstances.
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12. References
1 . https://en.wikipedia.org/wiki/Disc_brake
2. http://www.brembo.com/en/car/original-equipment/products/carbon-ceramic-discs
3. https://en.wikipedia.org/wiki/Gray_iron
4. http://machinedesign.com/basics-design/cast-iron
5. http://www.ask-chemicals.com/foundry-products/applications/brake-disc-casting.html
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