finite element analysis of disk brake assembly

Computer Aided Engineering MET-300 Project – Technical Report

Disc Brake Assembly Analysis

INSTRUCTOR: Dr. Gonca Altuger-Genc

MET-300

Mridul MohtaPragadeesh Ravichandran

Aditya Kaliappan Velayutham04/29/2015

Farmingdale State College 04/29/2015

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TABLE OF CONTENTS

1. Abstract……………………………………………………………….32. Parameters Involved………………………………………………….53. Parts of Braking System……………………………………………...54. Geometry of Contact Area…………………………………………...65. Objective……………………………………………………………..86. Procedure…………………………………………………………….87. Selection of Materials……………………………………………….108. Mechanical Properties……………………………………………....109. Outcomes

1) Analysis Type 1 – Mechanical Event Simulation……………….14Material A

2) Analysis Type 1 – Mechanical Event Simulation……………….20Material B

3) Analysis Type 2 – Non-Linear Static Stress Simulation………...24Material A

4) Analysis Type 2 – Non-Linear Static Stress Simulation………...29Material B

10.Challenges Faced……………………………………………………3411.Formulae…………………………………………………………….3512.Computational Problem……………………………………………..3613.Design for Manufacturing of Disc Brakes…………………………..3814.Conclusion…………………………………………………………..3915.References…………………………………………………………...40


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Abstract

Disc Brakes are the type of the brakes, which uses the pair of calipers attached with the brake pads to rub against the disc. This creates friction between the brake pads and the disc, which in turn reduces the rotatory motion of the axle/wheel or brings it to stationary. Braking systems rely on friction to bring the vehicle to a halt – hydraulic pressure pushes brake pads against a cast iron disc. It consists of a disc made up of cast iron, which is bolted, to the wheel hub and a caliper (stationary mount housing). The caliper is linked to the vehicle’s stationary part like the axle casing and holding pistons in each part. In between each piston and the disc there is a friction pad held in position by retaining pins, spring plates etc. Passages are drilled in the caliper for the fluid to enter or leave each housing.

Failure of disc brakes - If brake pads are not changed promptly, scarring occurs. This happens once they reach the end of their service life. Cracking takes place only for drilled discs that may develop small cracks around edges of holes drilled near the edge of the disc because of the disc's non-uniform rate of expansion. The discs have a certain amount of "surface rust". Sometimes when the brakes are applied, a high-pitched squeal occurs. Most brake squeal is produced by vibration (resonance instability) of the brake components, especially the pads and discs (known as force-coupled excitation).

The standard disc brake of a 4-wheeler model was done using Autodesk Mechanical Simulation through which the properties like deflection, heat flux and temperature of disc brake model were calculated. It is important to understand action force and friction force on the disc brake new material, how disc brake works more efficiently, which can help to reduce the accident that may happen at anytime.


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Figure 1

Figure 2


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Parameters involved

Clamping Force

Braking Force

Braking Torque

Load torque

Inertia torque

Rubbing speed

Power dissipation

Kinetic energy

Friction torque

Braking time

Maximum disc speed

Deceleration during braking

Delay time for brake signal

External load acting on the brake

Parts of Braking System

Brake Pedal—force input to system from driver Design gives a Mechanical Advantage Master Cylinder—converts force to pressure Pressure is used to move brake pads into place Brake Pads—provide friction force when in contact with rotor Works to slow or stop vehicle Caliper—holds pads and squeezes them against rotor Rotor—spins with wheel


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When used in conjunction with brake pads, slows vehicle Vents—help provide cooling to brake

► Different materials have different coefficients of friction► Pad material can be chosen for performance or to create a balance between

performance and durability

Table 1Geometry of Contact Area

Figure 3F = Force on padsθ1, θ2, r1, r0 = Dimensions of brake pad


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Figure 4

► Step 1: Force is applied to by driver to the master cylinder

► Step 2: Pressure from the master cylinder causes one brake pad to contact rotor

► Step 3: The caliper then self-centers, causing second pad to contact rotor


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Objective

To develop a technical report by showing the simulation results of the disc brake assembly for different materials by providing the necessary tables/figures/graphs and to examine whether the part fails or not based on the safety factor requirements.

The disc brake assembly (Figure 5) on which the analysis has to be done –

Figure 5Procedure

1. The disc brake assembly file was downloaded as an Autodesk Inventor file.2. The unnecessary parts of the assembly were removed so as to reduce the

complexity of the project.3. The entire assembly was cut into half in two different planes. This was done

to reduce the simulation time.4. The final assembly had three parts – one caliper, brake pad and the rotor.5. The assembly was then opened in the Autodesk Simulation software.6. The assembly was meshed by selecting the appropriate 3D Mesh settings and

by clicking “Generate 3D Mesh” command.7. Once meshing has been done, both the element definition and element type

were defined.8. The analysis was carried with two different sets of materials for caliper, brake

pad and rotor. (Details mentioned later in this report)


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9. The analysis was carried with three different simulation types. (Details mentioned later in this report)

10. The next step was to define the constraints as follows: - For rotor’s inner side face - fixed constraint, For calipers – fixed constraint andFor brake pad – fixed except translational in z-axis

Constraints remained the same for Linear and Non - Linear Static Analysis.In addition, rotation of the rotor along the z-direction was set free for MES Type.

11. Linear Static Analysis – The surface of the brake pad, which faces the rotor, was simulated so

that it moves a certain distance by providing the option of prescribed displacement.

This was done by Selecting the surface Right click, select sub entities and then the vertices were chosen.

Then one of the nodes was right clicked and prescribed nodal displacements were selected.

The translational motion magnitude was given as 10.666 mm in negative z - direction and then the load curve was selected for an addition of the return cycle.

On the same surface, by following the steps mentioned above, nodal forces were applied for 1000 N along the same direction as that of the prescribed displacement.

The simulation was then made to run.12. Non – Linear Static Analysis – The same procedures were followed as that

of the Linear Static Analysis. In addition, Surface-to-Surface contact was defined between the meeting faces of the brake pad and the rotor. Although, the outcomes were observed to be different.

13. Mechanical Event Simulation type – The same procedures were followed as that of the Non – Linear Analysis. In addition, two more steps were added i.e.

Nodal Prescribed Displacement on the rotor - the inner hollow surfaces of the rotor was selected by drawing a circle over it. In the option mesh, the joint option was selected to create a joint.

For making the rotation possible, the rotor’s element definition was changed from truss to beam, which has rotational degree of freedom.

The selection type was changed to rectangle and dragged over the created joint. The nodes been selected was then right clicked to choose nodal prescribed displacements and the value of rotation in terms of number of revolutions was provided.


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Capture rate – It analyzes the component in several steps and increments. More is the value of the capture rate, better is the simulation result.

Under the parameters section, the capture rate was selected and defined as 5 for 1-second forward cycle.

So, for a total of 2 seconds, the total time of 10 seconds was made as a capture rate.

Selection of Materials

• The brake disc or rotor is usually made up of cast iron, but in some cases it is made up of composites such as reinforced carbon–carbon or ceramic matrix composites.

• We have used two different sets of material type. They are: -a. Caliper: Aluminum 6061 - O Brake Pad: ASTM Steel A36 Rotor: Cast Iron ASTM A48 Grade 50b. Caliper: Aluminum 6061 - O Brake Pad: Steel AISI 4130 Rotor: Titanium Carbide (TiC)

Mechanical Properties

Aluminum 6061 – O [Caliper Material]

Metric English

Hardness, Brinell 30 30

Ultimate Tensile Strength 124 MPa 18000 psi

Tensile Yield Strength 55.2 MPa 8000 psi

Elongation at Break 25 % 25 %


Modulus of Elasticity 68.9 GPa 10000 ksi

Ultimate Bearing Strength 228 MPa 33100 psi

Bearing Yield Strength 103 MPa 14900 psi


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Poisson's Ratio 0.33 0.33

Fatigue Strength 62.1 MPa 9000 psi

Machinability 30 % 30 %

Shear Modulus 26 GPa 3770 ksi

Shear Strength 82.7 MPa 12000 psi

ASTM A36 Steel [Brake Pad Set - 1]

Tensile Strength, Ultimate 400 - 550 MPa 58000 - 79800 psi

Tensile Strength, Yield 250 MPa 36300 psi


Modulus of Elasticity 200 GPa 29000 ksi

Bulk Modulus 160 GPa 23200 ksi

Poisson’s Ratio 0.26 0.26

Shear Modulus 79.3 GPa 11500 ksi

AISI 4130 Steel, normalized at 1600°F [Brake Pad - Set 2]

Hardness, Brinell 197 197

Hardness, Knoop 219 219

Hardness, Rockwell B 92 92

Hardness, Rockwell C 13 13

Hardness, Vickers 207 207

Tensile Strength, Ultimate 670 MPa 97200 psi

Tensile Strength, Yield 435 MPa 63100 psi


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Elongation at Break 25.5 % 25.5 %

Reduction of Area 60 % 60 %

Modulus of Elasticity 205 GPa 29700 ksi

Bulk Modulus 140 GPa 20300 ksi

Poisson's Ratio 0.29 0.29

Izod Impact 87 J 64.2 ft-lb

Machinability 70 % 70 %

Shear Modulus 80 GPa 11600 ksi

Gray Cast Iron Grade 50 [Rotor Set - 1]

Compressive (Crushing) Strength 1130 MPa (164 x 103 psi)

Density 7.2 g/cm3 (450 lb./ft3)

Elastic (Young's, Tensile) Modulus 130 to 160 GPa (19 to 23 x 106 psi)

Elongation at Break 1 %

Fatigue Strength (Endurance Limit) 148 MPa (21 x 103 psi)

Fracture Toughness 650 MPa-m1/2

Melting Onset (Solidus) 1090 °C (1990 °F)

Shear Strength 503 MPa (73 x 103 psi)

Specific Heat Capacity 450 J/kg-K

Strength to Weight Ratio 48 to 57 kN-m/kg

Tensile Strength: Ultimate (UTS) 345 to 410 MPa (50 to 59 x 103 psi)

Tensile Strength: Yield (Proof) 228 MPa (33 x 103 psi)

Thermal Conductivity 46 W/m-K

Thermal Diffusivity 14


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Thermal Expansion 10.5 µm/m-K

Titanium Carbide [Rotor Set - 2]Knoop Micro hardness 2400 2000 – 2400

Hardness, Rockwell A 93 93

Vickers Micro hardness 3200 3200

Tensile Strength, Ultimate 258 MPa 37400 psi

Modulus of Elasticity 448 - 451 GPa 65000 - 65400 ksi

Poisson’s Ratio 0.18 - 0.19 0.18 - 0.19

Shear Modulus 110 - 193 GPa 16000 - 28000 ksi

Shear Strength 89.0MPa@Temperature 1925 °C

12900psi@Temperature 3497 °F

The assembly (Figure 6) looked like the following upon meshing–

Figure 6Outcomes


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1. Analysis Type 1 – Mechanical Event SimulationMaterial A - Caliper: Aluminum 6061 - O Brake Pad: ASTM Steel A36 Rotor: Cast Iron ASTM A48 Grade 50Prescribed Displacement – 10.666 mm in the negative z-directionForce – 1000 N in the negative z-directionLoad Curve - GradualSurface-to-Surface Contact – Rotor’s outer surface & brake pad’s inner surfaceCapture Rate – 10 seconds

The assembly (Figure 1.1) looked like the following before the analysis was done-

Figure 1.1

Maximum Displacement – 10.67 mm


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Figure 1.2

Maximum Stress – 3207.31 N/mm2

Figure 1.3

Maximum Strain – 0.0298476 mm/mm


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Figure 1.4

Graph (Figure 1.5) shows maximum stress that the disc brake can handle under the applied load and the given material conditions -

Figure 1.5Factor of Safety – 0.1142


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Figure 1.6

The pictures listed above reveal that when the disc brake assembly is at the 5 th

step, the stress induced by the brake pad is more than the disc brake assembly at 10 th step i.e. rotor at 5th step has maximum stress of 3207 N/mm2 than at 10th step. This is because when the rotor undergoes maximum deflection due to the force applied by the brake pad (5th step) while being fixed at one end, it bends to the extent, which induces more stress in it. Thus, at the maximum limit (5th step) stress concentration is higher than when it reaches the 10th step. This disturbs the original configuration of the rotor and it can never return back to its initial position after continuous and/or repeated use.

The picture (Figure 1.7) to show that the load curve is gradual loading –


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Figure 1.7

Table 1.1

The brake pad’s material is ASTM A36 Steel, which is a ductile material and the rotor’s material is Cast Iron ASTM A48 Grade 50, which is also a ductile material.

As it is clearly seen from the safety factor plot that the Factor of Safety (FOS) is 0.1142 < 1.0. This shows that the disc brake fails and cannot bear the stress. Also, it can be seen from the above table (Table 1.1) that the minimum factor of safety for ductile material under static load condition is 2.0. So, any value below 2.0 shows that, the disc brake is not in par with the industrial standards. The failure is unavoidable hence; it is not safe and unacceptable.

The analysis was also done by providing the load curve as repeated and impact loading. However, this did not affect the outcome of the analysis and the results were the same as that of the gradual loading. The factor of safety requirements for ductile material is more for repeated and impact loading i.e. 8 and 12 respectively.

Load Curve – Repeated Loading


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(Figure 1.8)

Load Curve – Impact Loading

(Figure 1.9)

2. Analysis Type 1 – Mechanical Event Simulation


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Material B - Caliper: Aluminum 6061 - O Brake Pad: Steel AISI 4130 Rotor: Titanium Carbide (TiC)Prescribed Displacement – 10.666 mm in the negative z-directionForce – 1000 N in the negative z-directionLoad Curve - GradualSurface-to-Surface Contact – Rotor’s outer surface & brake pad’s inner surfaceCapture Rate – 10 seconds

The assembly (Figure 7) looked like the following before the analysis was done –

(Figure 7)



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Figure 2.1


Figure 2.2



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Figure 2.3

Graph (Figure 2.4) shows maximum stress that the disc brake can handle under the applied load and the given material conditions -

Figure 2.4

Factor of safety – 0.245508


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Figure 2.5


step, the stress induced by the brake pad is more than the disc brake assembly at 10 th step i.e. rotor at 5th step has maximum stress of 4832.57 N/mm2 than at 10th step. This is because when the rotor undergoes maximum deflection due to the force applied by the brake pad (5th step) while being fixed at one end, it bends to the extent, which induces more stress in it. Thus, at the maximum limit (5 th step) stress concentration is higher than when it reaches the 10th step. This disturbs the original configuration of the rotor and it can never return back to its initial position after continuous and/or repeated use.



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Figure 2.6

Table 2.1

The brake pad’s material is Steel AISI 4130, which is a ductile material and the rotor’s material is Titanium Carbide (TiC), which is also a ductile material.

As it is clearly seen from the safety factor plot that the Factor of Safety (FOS) is 0.245508 < 1.0. This shows that the disc brake fails and cannot bear the stress. Also, it can be seen from the above table (Table 2.1) that the minimum factor of safety for ductile material under static load condition is 2.0. So, any value below 2.0 shows that, the disc brake is not in par with the industrial standards. The failure is unavoidable hence; it is not safe and unacceptable.


3. Analysis Type 2 – Non-Linear Static Stress SimulationMaterial A - Caliper: Aluminum 6061 - O


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Brake Pad: ASTM Steel A36 Rotor: Cast Iron ASTM A48 Grade 50Force – 1000 N in the negative z-directionLoad Curve – Gradual


Figure 8


Figure 3.1



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Figure 3.2


Figure 3.3


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Graph (Figure 3.4) shows maximum stress that the disc brake can handle under the applied load and the given material conditions –

Figure 3.4

Factor of Safety – 14.7624

Figure 3.5


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step, the stress induced by the brake pad is more than the disc brake assembly at 10 th step i.e. rotor at 5th step has maximum stress of 21.7096 N/mm2 than at 10th step. This is because when the rotor undergoes maximum deflection due to the force applied by the brake pad (5th step) while being fixed at one end, it bends to the extent, which induces more stress in it. Thus, at the maximum limit (5 th step) stress concentration is higher than when it reaches the 10th step. This disturbs the original configuration of the rotor and it can never return back to its initial position after continuous and/or repeated use.


Figure 3.6

Table 3.1

The brake pad’s material is ASTM A36 Steel, which is a ductile material and the rotor’s material is Cast Iron ASTM A48 Grade 50, which is also a ductile material.

As it is clearly seen from the safety factor plot that, the Factor of Safety (FOS) is 14.7624 > 1.0. This shows that the disc brake do not fail and can bear the stress. Also, it


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can be seen from the above table (Table 3.1) that the minimum factor of safety for ductile material under static load condition is 2.0. So, any value above 2.0 shows that, the disc brake is in par with the industrial standards. The failure is avoidable hence; it is safe and acceptable.


4. Analysis Type 2 – Non-Linear Static Stress SimulationMaterial B - Caliper: Aluminum 6061 - O Brake Pad: Steel AISI 4130 Rotor: Titanium Carbide (TiC)Force – 1000 N in the negative z-directionLoad Curve – Gradual


Figure 9


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Figure 4.1


Figure 4.2


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Figure 4.3

Graph (Figure 4.4) shows maximum stress that the disc brake can handle under the applied load and the given material conditions –

Figure 4.4


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Factor of Safety – 47.5378

Figure 4.5


step, the stress induced by the brake pad is more than the disc brake assembly at 10 th step i.e. rotor at 5th step has maximum stress of 23.7365 N/mm2 than at 10th step. This is because when the rotor undergoes maximum deflection due to the force applied by the brake pad (5th step) while being fixed at one end, it bends to the extent, which induces more stress in it. Thus, at the maximum limit (5 th step) stress concentration is higher than when it reaches the 10th step. This disturbs the original configuration of the rotor and it can never return back to its initial position after continuous and/or use.


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Figure 4.6

Table 4.1

The brake pad’s material is Steel AISI 4130, which is a ductile material and the rotor’s material is Titanium Carbide (TiC), which is also a ductile material.

As it is clearly seen from the safety factor plot that the Factor of Safety (FOS) is 47.5378 > 1.0. This shows that the disc brake do not fail and can bear the stress. Also, it can be seen from the above table (Table 4.1) that the minimum factor of safety for ductile material under static load condition is 2.0. So, any value above 2.0 shows that, the disc brake is in par with the industrial standards. The failure is avoidable hence; it is safe and acceptable.



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Challenges Faced

In order to reduce the simulation’s complexity, most of the parts, which play no and/or less role, were removed from the actual assembly (Figure 10).

Figure 10 - Actual Assembly To avoid simulating symmetrical parts and reduce simulation time, the assembly

is further divided into half in two different planes (Figure 11). This helped in bringing down the size of the actual assembly.

Figure 11 - Assembly after removing the parts In spite of providing all the necessary requirements for the simulation, the rotor

was unable to rotate in the desired way. Certain analyses under particular conditions were not functioning properly

(Figure 7).


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Figure 12

Applying different commands and options like remote force, remote loads and constraints, which we haven’t been acquainted before was one of the major issues.

Formulae

Stress = Force/Area = F/A

Strain = Change in length/original length = dl/l

Young’s Modulus, E = Stress/Strain

Poisson’s Ratio = Lateral Stain /Longitudinal Strain

Factor of Safety = Ultimate Tensile Strength/ Maximum Stress

Computational Problem

Standard Brake DesignRotor disc dimension = 240 mm (240×10-3 m)Rotor disc material = Carbon Ceramic MatrixPad brake area = 2000 sq.mm (2000E-6 m)Pad brake material = AsbestosCoefficient of friction (Wet Condition) = Ranges between 0.07-0.13Coefficient of friction (Dry Condition) = Ranges between 0.3-0.5


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Maximum temperature subjected to = 350°CMaximum pressure subjected to = 1MPa (E6 Pa)

Forces Acting On Rotor Due To Contact with Brake Pads

Tangential force between pad and rotor (Inner face) FTRI = µ1.FRIWhere, FTRI = Normal force between pad brake and Rotor (Inner) µ1 = Coefficient of friction = 0.5 FRI = Pmax / 2 × A pad brake areaSo, FTRI = µ1.FRI FTRI = (0.5)(0.5)(E6 N/sq.m) (2000E6 sq.m) FTRI = 500 N

Tangential force between pad and rotor (outer face), FTRO.In this FTRO equal FTRI because same normal force and same material

Brake Torque (TB): With the assumption of equal coefficients of friction and normal forces FR on the inner and outer faces: TB = FT.RWhere TB = Brake torque µ = Coefficient of friction FT = Total normal forces on disc brake, [FTRI + FTRO] FT = 1000 N R = Radius of rotor discSo, TB = (1000) (120E-3) TB = 120 N.m

Brake Distance (x) – We know that tangential braking force acting at the point of contact of the brake, andWork done = FT. x (Equation A)Where FT = FTRI + FTRO X = Distance travelled (in meter) by the vehicle before it come to rest.We know kinetic energy of the vehicle.Kinetic energy = (m.v^2) / 2 (Equation B)Where m = Mass of vehicle v = Velocity of vehicleIn order to bring the vehicle to rest, the work done against friction must be equal to kinetic energy of the vehicle.


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Therefore equating (Equation A) and (Equation B) FT. x = (m.v^2) / 2Assumption v = 100 km/hr = 27.77 m/s M = 132 kg. (Dry weight of Vehicle)So we get x = (m.v^2) / 2 FT x = (132×27.772) / (2×1000) m. x = 50.89 m Heat Generated (Q) = M.Cр.ΔT J/s Flux (q) = Q/A W/m² Thermal Gradient (K) = q / k K/m

Carbon Ceramic Matrix –Heat generated Q= m*cp*∆TMass of disc = 0.5 kgSpecific Heat Capacity = 800 J/kg°CTime taken Stopping the Vehicle = 5 secDeveloped Temperature difference = 15°CQ = 0.5 * 800 * 15= 6000 JArea of Disc = Π * (R^2 – r^2) = Π * (0.120^2 – 0.055^2) = 0.03573 sq.mHeat Flux = Heat Generated /Second /area = 6000 / 5 / 0.0357 = 33.585 kw/sq.mThermal Gradient = Heat Flux / Thermal Conductivity = 33.582E3/40 = 839.63 K/m

Design for Manufacturing of Disc Brakes


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Figure 13

Conclusion


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From the results of the simulation and the shown computations, it was found that the braking force and the number of times the brake has been applied, has a direct relationship on the life and efficiency of the disc brake assembly.

More is the load applied on the brake pad; more is the force transmitted onto the rotor and enables it to quickly come to rest. The area where the brake pad rubs the rotor generates more stress and displacement. As the brake pad is comparatively smaller than the rotor, it has less factor of safety while being simulated. As the braking force is not directly applied to the rotor, and passed on through the brake pad in between, it is essential to know about the amount of force applied on the brake pad rather than knowing about the rotor’s factor of safety.

Non-Linear Static Stress analysis is preferred over Linear Static Stress analysis because it is a complex approach, which analyses the stress and strain more quickly and effectively. It is more accurate than the linear analysis because in linear analysis the basic assumptions are taken into consideration while the same assumptions are being violated in the non-linear analysis.

The conditions, which are being taken into account when non-linear analysis is considered, are dynamic loading or time dependent loading and large deformations of the component, which give the engineers an efficient way to analyze the part or component more properly and appropriately than the linear analysis.


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References

Abhang, Swapnil R., & Bhaskar, D.P. (2014, February). Design and Analysis of Disc Brake, International Journal of Engineering Trends and Technology (IJETT), Volume 8 Number 4 (ISSN: 2231-5381).

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Aluminum 6061 – O (n.d.). In ASM Aerospace Specification Metals Inc. online.Retrieved fromhttp://asm.matweb.com/search/SpecificMaterial.asp?bassnum=MA6061O

ASTM Grade 50 (ISO Grade 350, EN-JL 1060) Grey Cast Iron (n.d.). In Makeitfrom.com online.

Retrieved fromhttp://www.makeitfrom.com/material-properties/ASTM-Grade-50-ISO-Grade-350-EN-JL-1060-Grey-Cast-Iron/

Bobo (2013, January 15). Hydraulic Disc Brake. GrabCAD.Retrieved fromhttps://grabcad.com/library/hydraulic-disc-brake

Strength of Materials Basics and Equations | Mechanics of Materials Equations (n.d.). In Engineers Edge online.

Retrieved fromhttp://www.engineersedge.com/strength_of_materials.htm

Titanium Carbide (TiC) (n.d.). In MATWEB Material Property Data online.Retrieved fromhttp://www.matweb.com/search/datasheet.aspx?matguid=058d1b70edbd4b2293f298c52bbf9818&ckck=1


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http://www.matweb.com/search/datasheet.aspx?matguid=058d1b70edbd4b2293f298c52bbf9818&ckck=1

http://www.matweb.com/search/datasheet.aspx?matguid=058d1b70edbd4b2293f298c52bbf9818&ckck=1

http://www.engineersedge.com/strength_of_materials.htm

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http://www.makeitfrom.com/material-properties/ASTM-Grade-50-ISO-Grade-350-EN-JL-1060-Grey-Cast-Iron/

http://www.makeitfrom.com/material-properties/ASTM-Grade-50-ISO-Grade-350-EN-JL-1060-Grey-Cast-Iron/

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