thesis.docx

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DECLARATION
This is to certify that this project Thesis “Development and Analysis of Fiction
Characteristics of Organic Brake Pads Composite” in partial fulfilment of the requirement
for the award of the degree of B.Tech in Mechanical Engineering. I hereby declare that this
project submission represents my ides in my own words and where other ideas and words
have been included. I have adequately cited and referenced the original sources. I also declare
that I have adhered to all the principle of academic honesty and integrity and have not
misinterpreted or fabricated any idea/data/facts/source in my submission. I understand that
any violation of the above will be cause for disciplinary action by the University.
Tarun Kr Gupta (1501061254)
Sneh Kori (1501061069)
Shah Umar (1501061255)
Prashant Kumar (1504061006)
Mohd Afzal Javed (1503061017)

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CERTIFICATE
This is to certify that the Thesis entitled “Development and Analysis of Fiction
Characteristics of Organic Brake Pads Composite” in partial fulfilment of the requirement
for the award of the degree B.Tech in Mechanical Department submitted to
DIT UNIVERSITY, DEHRADUN during the academic year 2018-19 and is a bonafifide
research work carried out by
Sneh Kori (1501061269)
Shah Umar (1501061255)
Under my guidance and supervision
Signature
Prof. R.Rajan
(Mechanical Department)

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ACKNOWLEDGEMENT
At first I would like to express my sincere gratitude to my Project Guide “Prof.R.Rajan” for
giving me the opportunity to work on this topic. It would never been possible for us to be
able to take this project to this level without his supervision and his relentless support and
encouragement. We feel much honoured in presenting this dissertation report in such an
authenticable form of sheer endurance and continual efforts of inspiring excellence from
various coordinating factor of cooperation and sincere efforts drawn from all sources of
knowledge. We would also like to express our profound gratitude to Prof. Aftab Azeem for
guiding us during the manufacturing phase and all his valuable ideas.
We also wish to extend our gratitude towards Prof. Manoj Kumar, Head of Mechanical
Department, and DIT University for his support in providing all the facilities, which certainly
helped us in completing this dissertation report. The cooperation he gave us is greatly
appreciated.
Sneh Kori (1501061269)
Shah Umar (1501061255)
Signature
Prof. Manoj Kumar
HOD Mechanical

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CONTENTS
S.NO PARTICULARS PAGE NO
1. Candidate Declaration 01
2. Certificate 02
3. Acknowledgement 03
4. Contents 04
5. Chapter1: Introduction 05-06
6. Chapter 2: Literature review 07-13
7. Chapter 3: Frictional Lining Material 14-23
8. Chapter 4: Testing of Brake Pads Material 24-28
9. Chapter 5: Discussion and Conclusion 29-30
10. References 31

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CHAPTER 1
INTRODUCTION
1.1 BRAKE PAD
A brake plays a vital role in any automotive vehicle so as to slow down the vehicle or to stop
the vehicle completely. During application of brake, friction between brake pads and rotating
disc causes to stop the vehicle by converting kinetic energy of the vehicle into heat energy.
Therefore the brake pads should quickly absorb heat should withstand for higher
temperatures and should not wear. The brake pad material should maintain a sufficiently
high friction coefficient with the brake disc not decompose or break down in such a way that
the friction coefficient with the brake is compromised at high temperatures and exhibit a
stable and consistent friction coefficient with brake disc . In past years asbestos is used in
brake pads but asbestos caused carcinogenic effects on human health . It leads to the
investigation on new materials particularly agricultural residues or wastes are now emerging
as new and inexpensive materials in the brake pads development with commercial viability
and environmental acceptability for brake pad which possesses all required properties. There
are metallic, semi metallic and organic brake pad materials. Generally brake pad consists of a
composition of reinforced fibers, binders , filters and friction additives . All these constituents
are mixed or blended in varying composition and brake pad material is obtained using
different manufacturing techniques. Reinforced fibers increase mechanical strength to the
friction material, The purpose of a binder is to maintain the brake pads structural integrity
under mechanical and thermal stresses. It holds the components of a brake pad together and
to prevent its constituents from crumbling apart. Fillers in a brake pad are present for the
purpose of improving its manufacturability as well as to reduce the overall cost of the brake
pad .Abrasives and lubricants are considered as friction additives, abrasives in a friction
material increase the friction coefficient. They remove iron oxides from the counter friction
material as well as other undesirable surfaces films formed during braking. Lubricants
stabilizes developed friction coefficient at high temperatures.
1.2 Background
In the past asbestos was used to manufacture brake pads. Asbestos became increasingly
popular among brake pad manufacturers because of its sound absorption, average tensile
strength, and its resistance to heat, electrical and chemical damage. However, since 1970s,
asbestos had gained widespread acknowledgment as a carcinogen. This is because inhalation
of asbestos fibers can cause serious illnesses, including malignant lung cancer, mesothelioma
(a formerly rare cancer strongly associated with exposure to amphibole asbestos) and
asbestosis (a type of pneumoconiosis). Other asbestos-related diseases include; Asbestos
warts: caused when the sharp fibers lodge in the skin and are overgrown causing benign
callus-like growth. Pleural plaques: discrete fibrous or partially calcified thickened area
which can be seen on X-rays of individuals exposed to asbestos. Although pleural plaques are

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themselves asymptomatic, in some patients this develops into pleural thickening. Diffuse
pleural thickening: similar to above and can sometimes be associated with asbestos. Usually
no symptoms shown but if exposure is extensive, it can cause lung impairment. This led to
the use and development of other materials which could take the place of asbestos in the
manufacture of brake pads in automotive industry. These other materials include; metals,
ceramics, carbon and organic materials. However these materials have different advantages
and disadvantages when solely used to construct a brake pad. Hence more research is being
carried on a combination of different materials so as to optimize the performance
requirements.
1.3 Problem Statement
From the previous project research undertaken by our Seniors different brake pads were
construction and tested in the laboratories. The tests carried out were test, compressive
strength, thickness swell and the Rockwell hardness test. The result obtained from all the test
were seemed satisfactory and were plotted on a bar graph with the conclusion that
compressive strength, hardness, wear of different samples were seen to decrease with
increase in percentage of principles leaf fibre. The research showed that the principle leaf
fibre can be effectively used as a replacement of commercial brake pad.
1.4 Objective
The main objective of this project is to develop a suitable material for brake pad that can
replace asbestos and provide braking properties similar to brake pads and which could be
eco-friendly at the same time.

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CHAPTER 2
LITERATURE REVIEW
S.no Name of Journals Name of authors Input Parameters Results
1. Recent Development in
Non-Asbestos fiber
Reinforcement
JAYASHREE
BIJWE
 The phenolic resin exhibit
high steady state µ, bt poor
wear resistance.
 Inclusion of Kevlar fibres
result in
1. Decrease in adhesive
force in mating surface.
2. Reducing µ (without
fibers)
3. Stabilising µ compared
with phenolic resin.
4. Enhancing wear
resistance substantially
30-40 times.
5. Reducing µ to a steady
state less drastically as
compared with resin
when water is
lubricated.
6. Increasing wear rate
when water is
lubricated.
Heat treatment and
processing parameters
influenced the physic-
mechanical and
tribological
performance.
Among various
binders, novolac resin
displayed the best
performance, stable µ
at 350ᵒ-450ᵒC
Among the selected
composites, basalt
fiber composites
exhibited good physic-
mechanical and
tribological properties.
The Optimum
concentration of fibers
for a highly stable µ at
all selected high
temperature was 7%
by wt.
Only Aramid
composite transferred a
fiber material on the
counterface.

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2. Recent Development in
Non-Asbestos fiber
Reinforcement
JAYASHREE
BIJWE
 For investigating the
simultaneous influence of
Cu Powder, BaSO4, and
cashew dust on friction and
wear of brake pads.
 Selected three series of
several composites
containing five ingredients.
20% phenolic resin and 20%
Aramid Fibres was mixed
along with Cu powder,
BaSO4 and Cashew dust,
the amount of one
ingredient was and other
two was varied from 0% to
40%.
 Tribo-evaluation of these
composites was done on a
slider-on-disc type wear
tester under different
conditions.
Cu powder inclusion
resulted in increase in
fade resistance and
decrease in wear
resistance.
BaSO4 inclusion led to
the exactly opposite
behaviour, a decrease
fade resistance and an
increase wear
resistance and strength.
SEM studies indicated
that a large part of the
layer from the worm
surface was peeled off
as a result of repetitive
sliding.
In case of Cu-powder-
cashew dust
combination, specific
wear rate increased
with increasing
amount of Cu powder.
Maximum fade
resistance and high
friction properties were
exhibited when both
ingredients were 20%
of wt.

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3. Effect of Zinc borate and
Fly-ash on Tribological
characteristics of Brake
friction materials.
B Ozturk & T
Mutlu
The composites had a fixed
compositions of 15% wt
Resin, 15% wt Fibers, 5%
wt friction additives.
Zinc Borate and Fly Ash
were added as filler to the
raw materials mixture at
total fraction of 65% by wt.
The best fade
resistance was
obtained for
composites containing
0-5% zinc borate and
60-65% wt of Fly ash.
The highest and the
lowest coefficient were
recorded for friction
composites Z- 5% F-
60% and Z-35% F-
30% while the friction
composites Z-35% F-
30% and Z-0% F-65%
The average particle
size of the friction
composites increases
with increasing Zinc
Borate and decreasing
Fly ash.

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2.2 Brakes
A brake is a device which retards motion. A friction brake is a type of an automotive brake
that stops or slows down a vehicle by converting the kinetic energy into heat energy. Most
brakes use friction to convert kinetic energy into heat energy, although other methods of
conversions can be employed, for e.g. regenerative braking convers most of the energy to
electrical energy which may be stored for other use. Other methods convert kinetic energy
into potential energy in the form such as pressurized oil or air. Still other braking methods
even transform kinetic energy into other different form, for e.g. Transferring the energy to a
rotating flywheel.
2.3 Braking System
Modern automotive brake system has been refined for over hundred years and has become
extremely efficient and reliable. The typical brake system consists of disc brake in front of
either of the disc or drum brakes in the rear connected by a system of hoses and tubes that
links the brake at each wheel to the master cylinder. When one presses the pedal, he/she
pushes against a plunger in the master cylinder which forces brake fluid (hydraulic oil)
through a series of hoses and tubes to the braking units at each wheel. On a disc brake the
fluid from the master cylinder is into the callipers where it presses a piston .The piston then
squeezes the brake pads against the rotor that is attached to the wheel, forcing it to slow down
the vehicle.
Fig 2.3a Original Brake Pads

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2.4 Frictional lining
The friction linings in the brake pads are the primary wear element for the brake system. This
part of brake pads is designed to contact with the rotor converting kinetic energy to heat and
as a result, it gradually wears and until it gradually wears out until it needs replacement. Of
all the brake pads parts, the friction material is without a doubt the most important and
critical from a high performance perspective.
2.5 Categories of frictional lining
Frictional linings can be categorized by according to the composition of the materials used in
the manufacturing. The categories are:
2.5.1 Metallic pads
The metallic pads are typically made of copper, Iron, steel and graphite all mixed together to
form the brake pad material. These pads are durable and cost-effective. They also transfer the
heat generated by friction with the brake rotors. However, these pads are very hard. This
makes them to create more wear on the brake rotors. They don’t work well when used in a
cold environment; they are noisy and create dust.
2.5.2 Asbestos pads
Asbestos was the best choice of material on the manufacturing of brake pads. This is due to
its good properties such as ability to withstand high temperatures and low thermal
conductivity which are essential for brake pads and it was easily available. However, in the
early 1980s it was found to be carcinogenic and was capable of causing asbestosis and
mesothelioma.
2.5.3 Ceramic pads
These pads are made up of ceramic compounds which area composition of about 15% metal
fibers and other ingredients such as binders, fillers, lubricants etc. These pads wear
comparatively less, transfer heat better because of the metal fibers and they are light in
weight.
2.5.3 Semi-metallic pads
These types of pads consist of about 40% metallic fibers and other ingredients which are
binders, fillers, lubricants etc. these pads also include pads that are carbon based. Semi-
metallic pads are strong, generate noise, conduct heat away from rotors and are abrasive
enough to increase rotor wear.

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2.6 Constituents of brake pad frictional lining
Brake pad frictional lining comprises of four different categories of materials. The
formulations must meet the following demand for the brake pad:
a) Maintain a sufficiently high coefficient of friction with the brake disc
b) Neither brake down nor decompose in such a way that the friction coefficient with the
brake disc is compromised at high temperatures
c) Exhibit stable and consistent friction coefficient with brake disc.
Brake pad frictional lining have following categories of materials:
a) Fillers which improve the manufacturability of brake pads and reduce cost
b) Frictional additives which determine the frictional properties of brake pads and
comprise of a mixture of lubricants and abrasives.
c) Binder which holds components of a brake pad together.
2.6.1 Reinforcing materials
These are the materials used to provide mechanical strength to the friction lining. Research
has proved that braking load is actually carried by tiny plateaus that rise above the
surrounding lowlands on friction materials. These plateaus are formed by reinforcing fibers
surrounded by softer compacted components. Therefore the importance of the reinforcing
fibers in friction materials can’t be underestimated. Friction materials generally use a mixture
of different types of reinforcing fibers with complementing properties.
2.6.2 Fillers
It is a loose term which can also mean anything used in a large proportion in a brake friction
material for the purpose of improving its manufacturability as well as to reduce overall cost
of brake pad. Fillers are also used to maintain the overall composition of friction material.
Fillers are of two types; Functional fillers used to improve particular characteristic feature of
composites such as resistance to fade and inert fillers are mainly used to cut the cost.
2.6.3 Binders
The main function of a binder is to maintain the brake pad’s structural integrity in various
braking condition. Binders carry all the constituents of brake pad together and stop them from
disintegrating. Selection of binders for brake pads is hence an important task. Binder must be
heat resistant.

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2.6.4 Frictional additives
These are the components added to the frictional lining to aid in the modification of the
friction coefficient and wear rates. They can be categorized in two classes: lubricants and
abrasives.
According to experiment done by Jang and Kim on brake pads with varying quantity of
lubricants ( antimony sulphide) and abrasives ( zirconium silicate) it was discovered that
friction coefficient stability largely depended on the quantity of either lubricant or abrasive
and hence an optimum quantity of each must be tested before use. This is often done because
of the increase in the quantity of lubricants of abrasive materials in the lining leads to
increase in friction co-efficient stability while increase in quantity of abrasive material leads
to instability in friction co-efficient.
1. Lubricants- They are mainly used to stabilize the development friction coefficient
during braking especially at high temperature.
2. Abrasives- These are additives which increases the friction coefficient and the rate of
wear of the counter face material. They remove iron oxides from the counter friction
material as well as other undesirable surface films formed during braking. However,
friction material with larger abrasive content exhibits a greater variation of friction
coefficient. Examples of abrasive are hard particles of metal oxides and silicates.
COMPONENTS FUNCTION
FILLERS Improves Manufacturing
FRICITION MODIFIERS Acts as a Lubricant, modifies wear and
friction coefficient
REINFORCEMENT Provide mechanical strength
BINDER MATERIALS Maintain structural integrity

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CHAPTER 3
FRICTION LINING MATERIALS
3.1 MATERIALS REQUIREMENT:
Desirable properties for friction lining brakes
1. The frictional lining as well as the rotor materials should have a high coefficient of
friction.
2. The frictional lining material in contact with the rotor should resist wear effects.
3. The coefficient of friction must be constant over a range of pressures and
temperatures.
4. The materials should be resistant to the environmental effects such as moisture, dust,
pressure.
5. The materials should have low specific weight so as to improve on the fuel economy.
6. The materials should possess good thermal properties, high heat capacity and good
thermal conductivity.
7. The materials should have good shear strength which is transferred to friction forces.
The materials should be safe to use and not cause environmental pollution
3.2 CONSTITUENTS OF THE BRAKE PADS FRICTIONAL LINING
Evidently, it is difficult to find a material which has all the above characteristics and hence a
mixture of different materials is used to obtain characteristics which are close to the
requirement.
These different materials used are grouped into different categories. These categories are:
 Binders
 Reinforcing materials
 Fillers
 Frictional additives and
 Lubricants.
a) BINDERS: The function of the binders is to maintain the brake pad’s structural
integrity in various braking condition. Binders hold all constituents of a brake pad
together and prevent them from disintegrating. Selection of binders for brake pads is
hence an important issue. The binder should have a high heat resistance.
b) REINFORCING MATERIALS: These are the materials which is used to provide
mechanical strength to the friction lining. Research has shown that the braking load is
actually carried by tiny plateaus that rise above the surrounding on the friction
materials. These plateaus are formed by the reinforcing fibers surrounded by the
softer compacted components. Therefore the importance of reinforcing fibers in

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friction materials cannot be under-estimated. Friction materials typically use a
mixture of different types of reinforcing fiber--s with complementing properties.
c) FILLERS: It is a loose term which could also mean anything used in a large
proportion in a brake friction material for the purpose of improving its
manufacturability as well as to reduce the overall cost of the brake pad. Fillers are
often used to maintain the composition of the friction material.
Fillers are of two types:
a) Functional fillers- used to improve particular characteristics features of
composites such as resistance to fade.
b) Space/Inert fillers- used to cut the cost mainly.
d) FRICTIONAL ADDITIVES: These are components added to frictional lining and
in the modification of the friction coefficient and wear rates. They can be categorized
into two classes: lubricants and abrasives.
According to experiment done by KIM and JANG on brake pads with varying
quantity of lubricants (antimony sulphide) and abrasives (zirconium silicate) it was
discovered that friction coefficient stability largely depended on the quantity of
either lubricant or abrasive and hence an optimum quantity of each must be used.
e) LUBRICANTS: These are mainly used to stabilize the developed friction
coefficients during braking, especially at high temperatures. Increase in the quantity
of lubricants materials in the lining leads to increase in friction coefficient stability.
f) ABRASIVES: These are additives which increase the friction coefficients and the
rate of wear of the counter face materials. These remove iron oxides from counter
friction material and other undesirable surface films formed during braking.
Examples of abrasives particles are hard particles of metal oxides and silicates.

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3.3 CATEGORIES OF FRICTIONAL LINING MATERIAL
a) METALLIC PADS: These pads are typically made of iron, copper, steel and
graphite all mixed together and bonded to form the pad material. These pads are cost
–effective and durable. They are also good at transferring the heat generated by
friction with the brake rotors. However, being made of metal the pads are very hard.
This makes them to cause more wear on the brake rotors. They do not work well
when cold, they are noisy and dust.
b) ASBESTOS PADS: Asbestos was the best choice material in the manufacture of
brake pads. This is because of its good properties such as low thermal conductivity
and withstand high temperatures which are essential in brake pads. It was also
readily available. However, in the early 1980s it was discovered to be carcinogenic
and was capable of causing Asbestosis.
c) CERAMICS PADS: These pads are made of ceramics compounds which are a
composition of about 15% metal fibers and other ingredients such as fillers, binders
and lubricants. The various fillers and lubricants help dampen vibration and noise
and these pads are quiet in operation. These pads wear less, transfer heat better
because of metal fibers and are lighter in weight.
d) SEMI-METALLIC PADS: These pads consist of about 40% metallic fibers and
other ingredients which include fillers, binders and lubricants. These also include
pads which are carbon based semi-metallic pads are strong, conduct heat away from
rotors, generate noise and are abrasive enough to increase rotor wear.
e) ORGANIC BREAK PADS: Organic brake pads sometimes called as non-asbestos
organic brake pads are made from natural materials like glass and rubber, as well as
resins that can withstand high heat. In fact the high heat helps to bind the brake pads
materials together, Kevlar is also an important component in brake pads. An
advantage of organic brake pads including Kevlar pads is that they’re made of
materials that don’t pollute as they wear and they’re easier to dispose of, too.

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3.4 MANUFACTURING PROCESS
 First of all the materials in the sample was collected.
 Then the weight was measured
 All the materials were mixed together(expect epoxy) in a powder form
 Now the epoxy was diluted by heating in a burner so that the powder can be mixed
with it
 After mixing them we have to add our respective hardener to harden the material
 Now we have to pour the material in a pressing machine
 The temperature of a pressing machine is set to 100degree Celsius.
 And then the sample is left in the machine for 24 hours
 After 24 hours the sample is removed from the machine and further testing is done.
 The methodology is such adopted in order to achieve the objectives of this project and
is listed below.
 Mixing the preferred materials by using the chuck of lathe in order to get homogenous
mixture.
 Compacting the mixture with a varying the pressure 80,100,135 & 175mpa.
 Sintering the samples for 3 to 4 hours with the temperature of 4000 , 4500& 5000C.
 Conducting mechanical testing, studying the hardness & wear characteristics.
 Analysis sample characterization by using an optical microscope.

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3.5 PRINCIPLE FOR WORKING FOR PROJECT

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3.6 DIE MAKING
Fig 3.6 a, 3.6b Punch & Die

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3.7 a Input Parameters:
 The phenolic resin exhibit high steady state µ, bt poor wear resistance.
 Inclusion of Kevlar fibres result in
1. Decrease in adhesive force in mating surface.
2. Reducing µ (without fibers)
3. Stabilizing µ compared with phenolic resin.
4. Enhancing wear resistance substantially 30-40 times.
5. Reducing µ to a steady state less drastically as compared with resin when water is
lubricated.
6. Increasing wear rate when water is lubricated.
 For investigating the simultaneous influence of Cu Powder, BaSO4, on friction and wear of
brake pads.
 Selected three series of several composites containing five ingredients. 20% phenolic resin
and 20% Aramid Fibres was mixed along with Cu powder, BaSO4, the amount of one
ingredient was and other two was varied from 0% to 40%.
 Tribo-evaluation of these composites was done on a slider-on-disc type wear tester under
different conditions.
3.7 b Observations:
 Only Aramid composite transferred a fiber material on the counterface.
 Heat treatment and processing parameters influenced the physic-mechanical and tribological
performance.
 Among various binders, novolac resin displayed the best performance, stable µ at 150ᵒ-
200ᵒC
 Among the selected composites, basalt fiber composites exhibited good physic-mechanical
and tribological properties.
 The Optimum concentration of fibers for a highly stable µ at all selected high temperature
was 7% by wt.
Maximum fade resistance and high friction properties were exhibited when both ingredients
were 20% of wt.
 BaSO4 inclusion led to the exactly opposite behavior, a decrease fade resistance and an
increase wear resistance and strength.
 SEM studies indicated that a large part of the layer from the worm surface was peeled
off as a result of repetitive sliding.

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3.8 COMPOSITION TABLE
Name Composition
(Wt. %)
S-1 S-2 S-3 S-4
BINDER Phenolic Resin 25 30 35 38
REINFORCEMENT
FIBRE
Kevlar Fibre 5 5 5 5
Lapinus Fibre/glass
fibre
10 10 10 10
CONDUCTIVITY
MODIFIER
Steel Fibre 10 10 10 10
LUBRICANT Graphite 5 5 5 5
FILLER Barium Sulphate
(BaSo4)
45 40 35 32

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3.9 SAMPLE PREPARATIONS:
Fig 3.9a Press Machine Fig 3.9b Heating Operation
Fig 3.9c Heating Operation Fig 3.9d Composition Mixture

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Fig 3.9e Sample Brake Pad Fig 3.9f Brake Pad in Furnace
Fig 3.9g Samples

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CHAPTER 4
TESTING OF BRAKE PAD MATERIALS
Brake Material Test Methods and Apparatus
4.1 FAST TEST :
 The Friction Assessment And Screening Test ( FAST ) Machine by ford Motor
Company as quality assurance test .
 The Friction Assessment and Screening Test (FAST) machine, the friction tests
were performed in sample 1 for each material.Three friction test procedures
were applied and then the average of these three tests was recorded. For
comparison purposes, FAST testing were repeated with samples obtained.
 In The FAST Test we uses a pearlitic gray cast iron disc (diameter of 180 mm,
thickness 38 mm) and a brake lining test sample of dimensions
(12.7×12.7×5.00) mm. The test sample was at first mounted on the load arm
and pressed against the flat surface over a rotating disc.
 The rotating cast iron disc moves with a constant sliding speed of v = 7 m sec-
1
for 90 min and then temperature was increased from room temperature upto
300°C. Before performing the FAST testing, the surfaces of the test sample and
the cast iron discs was grounded with 320-grid sandpaper. The normal load was
frequently varied to achieve constant friction force.
 The friction coefficient was calculated by measuring normal and tangential
pressures every 5 sec during the 90 min test. The weight and thickness of brake
pads sample and a disc for each sample were taken before and after the friction
test.
 In order to achieve the average thickness, six measurements (three at the
beginning and three at the end) were observed at different positions on the
brake pad and disc before and after the friction test. Wear rate was calculated
as the amount of weight loss per mm2
of the sample during the tests.
Fig 4.1a FAST Machine

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4.2 HARDNESS TEST
After the brake pads were constructed a hardness test was to be conducted. The hardness test
used was Rockwell hardness test. This was preferred because; it can be used for non metals,
indenters are small hence it could not destroy the specimen, it is a high speed test and the
surface does not have to be reflective. This test consists of an indenter which is a diamond
cone with an angle of 1200 and a tip radius of 0.2mm or steel balls of various diameters. The
standard for this test is IS- 2742/1994. Main scale available are Rockwell C which uses a
diamond cone indenter and a load of 150 kg, Rockwell B where the indenter is 1/16 inch steel
ball of 100kg and Rockwell A which has same indenter as Rockwell C among others. In this
case Rockwell C was used. The test was done on different positions of the brake pad and an
average reading recorded.
4.3 ABRASION WEAR TEST
The aim of abrasion testing is to produce data that will reproducibly rank materials in there
resistance to scratching abrasion under a specific set of conditions. Standard abrasion testing
methods must be used to predict the exact resistance of given material on a specific
environment. Its values lie in ranking materials in a similar relative order of merit as would
occur in an abrasive environment, a customized wear testing program, on the other side, it
can be configured to closely mimic real operating conditions, including temperature and
fluids, and direction of wear.
Wear tests are carried out in sand wear type friction and wear monitoring test rig as per
ASTM UIC 854R. The experimental setup is shown. The counter body is a wheel is rotated
wheel made of hardened steel surface of (roughness 0.2ra). The specimen is held stationary
and the wheel is rotated while a normal force is applied through a lever mechanism and sand
rubs the test specimen against the wheel with sand in between them, a series of test are
conducted with three machine velocity if 200rpm for 20min, constant under 3 different
normal loading.
TEST CASE INITIAL WEIGHT
(gm)
FINAL WEIGHT
(gm)
MASS LOSS (due to
wear)
Sample 1 19.645 19.220 .425
Sample 2 18.853 18.489 .364

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4.4 SCANNING ELECTRON MICROSCOPE (SEM) TEST
A Scanning electron microscope (SEM) is a type of electron microscope that produces
images of a sample by scanning it with a focused beam of electrons. The electrons interact
with atoms in the sample, producing various signals that contain information about the
sample’s surface topography and composition. The electron beam is generally scanned in a
raster scan pattern and the beam position is combined with the detected signal to produce an
image. SEM can achieve resolution better than 1 nanometre. Non conductive specimens tend
to charge when scanned by the electron beam and especially in secondary electron imaging
mode, this causes scanning faults and other image artefacts’ for conventional imaging in
SEM, specimens must be electrically conductive, at least at the surface, and electrically
grounded to prevent the accumulation of electrostatic charge, metal objects require little
special preparation for SEM, specimens must be electrically conductive, at least at the surface
and electrically grounded to prevent accumulation of electrostatic charge.
Fig 4.4a: Unused Square Fig 4.4b: Used Square
Fig 4.4c: Unused Round pin Fig 4.4d: Used Round pin

27 | P a g e
CHAPTER 5
DISCUSSION AND CONCLUSION
5.1 RESULT:
We were able to design heat resistant brake pads of materials free of asbestos with improved
internal strength. The materials used in the design were locally available. The locally
available materials were used to construct formulations for samples 1,2 and 3 which were
then tested for hardness study. Since the materials were free of asbestos they can be used as
brake pad manufacturing materials. This indicates that materials used for mixture of brake
linings can be obtained locally instead of importing.
 The performance coefficient of friction (𝜇) has been observed to be highest in the
composite with the highest amount of Phenolic resin and decreasing consistently with
the decrease in the Phenolic resin
 Overall, the increased Phenolic resin content was observed to enhance the friction
performance, friction fade performance, friction fluctuations and friction stability
performance, hardness whereas the density remains the same.
5.2 MARKET POTENTIAL:
The brake friction products original equipment (OE) market is projection to grow. Market
growth is primarily driven by factors such as the increasing demand for lightweight and eco-
friendly brake friction products, stringent stopping regulations, availability of advanced
friction materials, and increasing production of vehicles. The objective of the study is to
analyze and forecast the brake friction products OE market for passenger cars, light
commercial vehicle (LCVs) and heavy commercial vehicle (HCVs). The report also segments
the OE market by product type (brake pad, shoe, liner, disc and drum) aftermarket by product
type. The aftermarket by market type original equipment supplier (OES) and independent
aftermarket (IAM), two-wheeler market by product tyoe (brake pad, shoe, liner, disc and
drum) and region (Asia-Oceania, Europe, North America and Rest of the World (ROW). The
research methodology used in the report involves primary and secondary sources. Secondary
sources include automotive and component-manufacturing association, paid databases and
directories. In the primary research stage, experts from related industries, manufacturers and
suppliers have been interviewed to understand thr present scenario and future trends of the
brake friction product market. The brake friction products market size in terms of volume and
value for various regions and product applications has been derived using forecasting
technique based on automobile demand and production trends. The oEM prices of brake
friction products have been verified through primary process.

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5.3 RECOMMENDATION
More research could still be done to achieve optimum brake pads from locally avaliable
materials. Some of the recommendations are:
i) Material should be processed to a fine finish before use as opposed to their use
innatural form which would help in improving the final quantity of the Brake
pads.
ii) Machines should be designed for the use in the manufacturing of brake pads using
the formulation.

29 | P a g e
REFERENCES
 Nandan Dadkar , Bharat S. Tomar et.al(2009) “Evaluation of flyash-filled and aramid
fibre reinforced hybrid polymer matrix composites (PMC) for friction braking
applications” elsevier Ltd volume 30.
 Nandan Dadkar , Bharat S. Tomar et.al(2009) “Performance assessment of hybrid
composite friction materials based on flyash–rock fibre combination” elsevier Ltd
volume 31.
 Tej Singh , Amar Patnaik , Ranchan Chauhan ” Assessment of braking performance of
lapinus–wollastonite fibre reinforced friction composite materials” Journal of King Saud
University – Engineering Sciences.
 Bijwe, J., 1997. “Composites as friction materials: recent developments in non-asbestos
fibre reinforced friction materials-a review.” Polym. Compos. 18 (3), 378–396.
 Singh, T., Patnaik, A., 2015a. Performance assessment of lapinusaramid based brake pad
hybrid phenolic composites in friction braking. Arch. Civil Mech. Eng. 15, 151–161.
 Tiwari, A., Jaggi, H.S., Kachhap, R.K., Satapathy, B.K., Maiti, S.N., Tomar, B.S., 2014.
Comparative performance assessment of cenosphere and barium sulphate based friction
composites. Wear 309, 259–268.
 Kumar, M., Satapathy, B.K., Patnaik, A., Kolluri, D.K., Tomar, B.S., 2011. Hybrid
composite friction materials reinforced with combination of potassium titanate whiskers
and aramid fibre: assessment of fade and recovery performance. Tribol. Int. 44, 359–367.

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