Ill attach the document that has the questions - Essay Example

Due to this pressure exerted on the pistons, the pistons in turn exert friction on the brake pads hence producing a clamping force on the rotating disc attached to the wheel disc. This clamping force is what is responsible for stopping the rotation disc hence the wheel. Figure 1 below shows the working principle of a braking system. [3] Figure 1 How do design & operational requirements influence material property requirements for the brake disc? The center of a brake disc contains bearings such that as the vehicle drivers presses the brake pad, the disc is mounted on the axle and is held in to place by the wheel.

When brakes are applied, a lot of heat is generated due to the friction between the braking surfaces. Therefore, materials chosen for the construction of the brake parts should be able to withstand very high temperatures. Also, the brake disc runs at a certain high speed in the process of stopping the motion of a wheel. [1] The most widely used brake disc material was cast iron but it was found to consume a lot of fuel due to its high specific gravity. This has seen exploitation of other lightweight materials to replace cast iron.

The materials for use in designing the brake disc must have a low cost per unit property and also meet the digital logic condition. Therefore, materials used for brake systems must have a stable and reliable frictional and wear properties under varying conditions of load, velocity, temperature and environment, and high durability. [6] Therefore the several factors to be considered when selecting a brake disc material include the ability of the brake disc material to withstand high friction and less abrasive wear and ability to withstand the high temperature evolved due to friction.

Another important factors that are of importance in consideration during the brake disc design is the cost of the whole process and the weight of the materials to be used. [1] Material selection exercise for brake disc One of the most fundamental ability of a material for the manufacture of a brake disc is the material to be able to reduce friction and less wear and tear. It must also be able to properly function even in high temperatures. The brake disc must also have enough thermal storage capacity to prevent distortion or cracking due to thermal stress.

This is not particularly important in a single stop but it is crucial in the case of repeated stops from high speed. Sometimes it may be unimportant to consider the cost of materials to be used if the material is to perform a critical function in space i.e. beryllium for structural components, iridium for radiation screening. Also in case it is to be used in medical procedures i.e. gold tooth fillings and in equipment for highly competitive sports for instance one racing motorcycle had a cylinder-head made of solid silver for its high thermal conductivity.

[12] The model for brake disc In Fig. 1 below, a brake disk can be idealized as two beams having length L, depth b and thickness h, locked together at their ends. Each of the beam is loaded in bending when the brake is applied, and because braking generates heat, it therefore gets hot. The stiffness S of the beam is also critical. If the stiffness is inadequate then the disc will flex, impairing braking efficiency and allowing vibration. Its ability to transmit heat, too, is critical since part of the heat