Friction - significant role in brake pads
Brake pads convert the kinetic energy of the car to thermal energy by friction.
Two brake pads are contained in the caliper with their friction surfaces facing the disc.
- When the brakes are hydraulically applied, the caliper clamps or squeezes the two pads together into the spinning rotor to slow or stop the vehicle.
- When a brake pad is heated by contact with a disc, it transfers small amounts of friction material to the disc. The brake pad and disc (both now with friction material), then "stick" to each other, providing the friction that stops the vehicle.
Did you know ? When a car brakes, the most important safety element in a braking system is smaller than the surface of a hand:
- - On this surface, the kinetic energy is transformed into heat and slows down and stops the vehicle.
- - On this surface, all physical features have to be mastered to ensure the vehicle handling
- - On this surface, all the vibrations have to be absorbed to avoid noise.
The friction level and its stability are of course key features to an efficient and safe system, the generated noises are as well crucial.