Imperial Journal of Interdisciplinary Research (IJIR)
Vol-2, Issue-6, 2016
ISSN: 2454-1362, http://www.onlinejournal.in
Manufacturing of Disc Brake Rotor Using
Aluminium Metal Matrix Composite
(AMMC) reinforced with Silicon Carbide
Parth S. Joshi, Kiran C. Hegade, Apoorv S. Kulkarni &
Omkar V. Karale
B. E. Students, Department of Mechanical Engineering, Trinity College of Engineering and
Research, Pune, India
Abstract: This paper deals with the manufacturing of
disc brake rotor using AMMC. AMMC is the
combination of aluminium and silicon carbide along
with small quantity of other material like magnesium,
aluminium oxide, graphite which are added in precise
quantity to enhance the chemical, mechanical and
thermal strength of material. The whole process is
carried out in controlled environment. Gravity die
casting is the suitable process used for the purpose.
Pre-processing of additives are carried out precisely.
Stir casting is one of the economical and extensively
used methods to enhance attractive properties of
AMC’s. This paper presents an overview of stir casing
process, process parameter and preparation of AMC
using aluminium alloy as matrix phase and alumina
(Al2O3) as reinforcement
Keywords:
Aluminium
reinforcement, stir casting.
Matrix
Composite,
1.Introduction
Aluminium alloys are used in advanced applications
because of high strength, low density, durability,
machinability, availability and cost is very attractive
compared to competing materials. The aluminum metal
matrix composite materials is the combination of two
or more constituents in which one is matrix and other is
filler materials (reinforcements). Aluminum metal
matrix may be laminated, fibers or particulates
composites. Generally, grey cast iron is used to
manufacture brake disc rotor, but AMMC is selected
considering crucial advantages of the AMMC over cast
iron material. Disc brake used for decelerating or
stopping the automobile or to maintain a constant
velocity or to park the vehicle. This specification
dictates the correct range of hardness, chemical
composition, tensile strength and other properties
Imperial Journal of Interdisciplinary Research (IJIR)
necessary for the intended use. Some racing cars and
airplanes use brakes with carbon fiber discs and carbon
fiber pads to reduce weight. In preparing metal matrix
composites by stir casting method some of the factors
that need considerable attention are as follows:
 To achieve uniform distribution of the
reinforcement material
 To achieve wettability between the two main
substances
 To minimize porosity in the cast metal matrix
composite
1.1 Brake Disc Rotor
The Disc Brake discs are commonly manufactured
out of grey cast iron. The SAE maintains a
specification for the manufacture of grey cast iron for
various applications. For Normal car and light truck
applications the SAE specification is J431 G3000
(superseded to G10). This specification dictates the
correct range of hardness, chemical composition,
tensile strength and other properties necessary for the
intended use. Some racing cars and airplanes use
brakes with carbon fiber discs and carbon fiber pads to
reduce weight. Wear rates tend to be high and braking
may be poor until the brake is hot. It is investigated
that the temperature distribution, the thermal
deformation and the thermal stress of automotive discs
have quiet close relations with car safety; therefore,
much research in this field has been performed.
1.2 Aluminium
(AMMC)
Metal
Matrix
Composite
The term “composite” broadly refers to a material
system which is composed of a discrete constituent
distributed in continuous phase, and which derives its
distinguishing characteristics from the properties of
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Imperial Journal of Interdisciplinary Research (IJIR)
Vol-2, Issue-6, 2016
ISSN: 2454-1362, http://www.onlinejournal.in
constituents, from the geometry and architecture of
constituents and from properties of the boundaries
between constituents. Composite materials are usually
classified on the basis of the physical or chemical
nature of the matrix phase e.g. polymer matrix, metalmatrix and ceramic composites. In AMCs one of the
constituents is Aluminium/ Aluminium alloy which
forms percolating network and is termed as matrix
phase. The other constituents are embedded in this
Aluminium/ Aluminium alloy matrix and serve as
reinforcement, which is usually non-metallic and
commonly ceramic such as SiC and Al2O3. The
properties of AMCs can be tailored by varying the
nature of constituents and their volume fraction.
The major advantages of AMCs compared too
unreinforced materials are as follows,










Greater strength
Improved stiffness
Reduced density (weight)
Improved high temperature properties
Controlled thermal expansion coefficient
Thermal/ heat management
Enhanced and tailored electrical performance
Improved abrasion and wear resistance
Control of mass (especially in reciprocating
applications)
Improved damping capabilities.
There has been interest in using Aluminium based
metal matrix composites for brake discs and drum
materials in recent years. While the friction and wear
of AMMCs were high speeds and loads the behavior
could be greatly improved beyond that of iron discs,
given the correct match of pad and disc material.
1.3 Reinforcement of Silicon Carbide
Silicon Carbide is the only chemical compound of
carbon and silicon. It was originally produced by a
high temperature electro-chemical reaction of sand and
carbon. Silicon carbide is an excellent abrasive and has
been produced and made into grinding wheels and
other abrasive products for over one hundred years.
Today the material has been developed into high
quality technical grade ceramic with very good
mechanical properties.
It is used in abrasives, refractoriness, ceramics and
numerous high-performance applications. The material
can also be made an electrical conductor and has
applications in resistance heating, flame igniters and
electronic components. Silicon carbide is composed of
tetrahedral of carbon and silicon atoms with strong
Imperial Journal of Interdisciplinary Research (IJIR)
bonds in crystal lattice. This produces a very hard and
strong material.
The properties of silicon carbide are described as
follows. Mechanically, silicon carbide has low density,
high strength, high hardness as well as high elastic
modulus. Thermal properties of silicon carbide are also
excellent as it has low thermal expansion, high thermal
conductivity and excellent thermal shock resistance.
Also it has superior chemical inertness.
As silicon carbide is added in the AMMC as a
reinforcement, it also reinforces the overall properties
of the AMMC. It improves the mechanical properties
of the AMMC, it increases the strength and hardness of
the composite. And also it improves the thermal
conductivity and thermal shock resistance of the
material.
2. Processing of AMMC’s:
Primary process for manufacturing of AMMC’s at
industrial scale can be classified into two main groups.
1) Liquid state processes:
a) Stir casting b) Infiltration process c) Reactive
processing d) Spray deposition
2) Solid state processes:
a) PM processing b) Diffusion bonding c) Physical
vapour deposition.
2.1 Stir casting:
Stir casting is a process in which uniformly mixed very
fine powder of additives are mixed with a molten
matrix metal by means of mechanical stirring. Stir
casting is the simplest and the most cost effective
method of liquid state fabrication. The liquid
composite material is then cast by conventional casting
methods and may also be processed by conventional
Metal forming technologies.
a. Stirrer
It is very important parameter in stir casting process
which is required for vortex formation. The blade angle
and number of blades decides the flow pattern of the
liquid metal. The stirrer is immersed till two third
depth of molten metal. All these are required for
uniform distribution of reinforcement in liquid metal,
perfect interface bonding and to avoid clustering.
Stirring speed decides formation of vortex which is
responsible for dispersion of particulates in liquid
metal. In our project stirring speed is 300
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Imperial Journal of Interdisciplinary Research (IJIR)
Vol-2, Issue-6, 2016
ISSN: 2454-1362, http://www.onlinejournal.in
rpm.
Figure 2. Pattern Dimensions
Figure 1. Stir Casting Process
b. Pre-Heating of Reinforcements:
Casting process is very difficult if reinforcement
particles are wet, also it results in non-uniform
distribution and poor mechanical property. To avoid
this problem, reinforcements are pre-heated at 500°C
for 40 minutes.
Figure 3. Casting Dimensions
c. Pre-Heating of Mould:
Porosity is the major problem in casting. In order to
avoid porosity preheating of mould is good solution. It
helps in removing the entrapped gases from the slurry
to go into the mould. It also enhances the mechanical
properties of the cast AMC. Mold is heated to 500°C
for one hour.
2.2 Preparation
pattern:
of
Patterns
design
and
In this step we have prepared patterns of
aluminium.
Figure 4. Aluminium Pattern
2.3 Mould Making Process:
In this step we have prepared mould for casting
specimen of various mechanical tests like tensile test,
hardness test, torsion test, etc. In order to avoid
porosity preheating of mould is good solution. It helps
in removing the entrapped gases from the slurry to go
Imperial Journal of Interdisciplinary Research (IJIR)
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Imperial Journal of Interdisciplinary Research (IJIR)
Vol-2, Issue-6, 2016
ISSN: 2454-1362, http://www.onlinejournal.in
into the mould. It also enhances the mechanical
properties of the cast AMC. Mold is heated to 500°C
for one hour.
Figure 7. Graphite Powder
Figure 5. Cope of the mould
Figure 8. silicon carbide powder
Figure 6. Drag of the mould
2.4 Preparation of reinforcement:
Precise quantity of reinforcements is weighted and
collected in crucible for moulding the composition of
AMMC is given below:
Aluminium Oxide (Al2O3): 1%
Silicon Carbide (SiC): 3%
Graphite: 2.5%
Magnesium (Mg): 1.5%
Aluminium (Al): 92%
Imperial Journal of Interdisciplinary Research (IJIR)
Figure 9. Aluminium Oxide Powder
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Imperial Journal of Interdisciplinary Research (IJIR)
Vol-2, Issue-6, 2016
ISSN: 2454-1362, http://www.onlinejournal.in
Figure 10. Magnesium Powder
Figure 11. Furnace
3. Preparation of aluminum based metal
matrix composite (AMMC):
Aluminium alloy is cleaned to remove dust
particles, weighed and charged in the crucible for
melting. Now reinforcement powder and magnesium
powder are weighed on the weighing machine, they are
pre heated for 45 minutes at a temperature 500. When
matrix was in the semisolid stage condition at 650°C, 1
% by weight of pure magnesium powder is used as
wetting agent. Heater temperature is then increased to
800oC. At this heater temperature stirring is started and
continued for five minutes. Stirring rpm is gradually
increased from 0 to 300 RPM with the help of speed
controller. Preheated reinforcements are added during
five minutes of stirring. Reinforcements are poured
manually with the help of conical hopper. Stirrer rpm is
then gradually lowered to the zero. Then molten
composite slurry is poured in mould without giving
time for reinforcement to settle down at crucible
bottom. Mould is preheated at 500°C temperature for
one hour before pouring the molten slurry in the
mould. This is necessary to maintain slurry in molten
condition throughout the pouring. Mould is then
allowed to cool and after cooling runner, riser are
removed from disc. Final finishing is done using lathe
machine to achieve dimensional accuracy.
Figure 12. Pouring of slurry
Figure 13. Machining of disc
Imperial Journal of Interdisciplinary Research (IJIR)
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Imperial Journal of Interdisciplinary Research (IJIR)
Vol-2, Issue-6, 2016
ISSN: 2454-1362, http://www.onlinejournal.in
Process. Mehran University Research Journal Of
Engineering & Technology, Volume 30, No. 1,
January, 2011 [Issn 0254-7821]
[5] Ajay Singh, Love Kumar, Mohit Chaudhary, Om
Narayan, Pallavsharma, Piyush Singh, Bhaskar
Chandra Kandpal, Som Ashutosh. MANUFACTURING
OF AMMCS USING STIR CASTING PROCESS AND
TESTING ITS MECHANICAL PROPERTIES Kandpal,
Et Al., International Journal Of Advanced Engineering
Technology E-ISSN 0976-3945
Figure 14. Final finished disc
4. Conclusion:
Following conclusion is drawn from above paper:
1. Gravity stir casting is most economical
process used for casting of AMMC.
2. Pre heating of mould reduces porosity and
enhances mechanical properties.
3. Pre heating of reinforcement results in
uniform distribution and better mechanical
properties.
4. Addition of Magnesium is important to
increase wettability.
[6] R.Kumar, J.Jegan, L.Initha, Processing Of
Aluminium Metal Matrix Composites (Ammc) Through
Stir Casting Route. IJME Volume 2, Issue 12,
December 2014.
[7] Rajeshkumar Gangaram Bhandare, Parshuram M.
Sonawane. (December 2013). Preparation of
Aluminium Matrix Composite by Using Stir Casting
Method. International Journal of Engineering and
Advanced Technology, Volume-3, Issue-2.
[8] Karnik Madhuri G., Sonawane Parushuram M.,
Kulkarni Swanand R., “Effect of graphite addition on
the mechanical properties of stir cast particulate
aluminium metal matrix composite reinforced with
alumina and silicon carbide.”, International
Conference
on
Design,
Manufacturing
and
Mechatronics 2014.
6. References
[1] Bharath V, Madev Nagaral, V Auradi and S. A.
Kori. (2014). Preparation of 6061Al- Al2O3 MMC’s by
Stir Casting and Evaluation of Mechanical and Wear
Properties. Procedia Materials Science 6, 1658 –
1667.
[2] M K SURAPPA. (February/April 2003).
Aluminium matrix composites: Challenges and
opportunities. Sadhana Vol. 28, Parts 1 & 2, pp. 319–
334.
[3] Shriyash S. Shinde, S. G. Kulkarni, S. S. Kulkarni
(2015). Manufacturing Of Aluminium Matrix
Composite Using Stir Casting Method. [IJIERT] ISSN:
2394-3696 VOLUME 2, ISSUE 5, MAY-2015
[4] Muhammad Hayat Jokhio, Muhammad Ibrahim
Panhwar And Mukhtiar Ali Unar. Manufacturing Of
Aluminum Composite Material Using Stir Casting
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