The brake disc is a very important engineering feature in the braking system. A brake disc can come in many sizes but is invariably round–which is why it’s called a disc. Though some break discs are solid throughout, a brake-disc can be made to have a systematic hole sequence throughout its body, which gives good cooling attributes. The cooling maximises braking performance and minimises brake fading. Brake fading can occur when the brakedisc heats up and becomes very, very hot. When it is too hot, the brake disc surface offers less friction when braking pressure is applied to it by the driver via the car’s braking system. What the driver will notice is that the car will not pull up as quickly and as sharply, and stopping distances are compromised.

The brake disc spins with the wheel, and the speed of the turning wheel can be slowed down by the driver’s decision to apply force to the brake pedal, which will transfer pressure via the braking system to two or more stationary pads situated in very close proximity to the rotating brake disc. The pressure applied via hydraulics will force the brake pads to clamp onto the rotating brake disc, creating an immense frictional force to be applied upon the brake disc. This will, in turn, slow down the speed of the vehicle’s wheel and thus its overall velocity. Obviously, the braking performance of a car can be greatly enhanced by fitting bigger brake discs than what may be fitted as standard. Needless to say, bigger faster cars need to have bigger and stronger brake discs to cope with the added engine power and overall speed that more powerful cars obtain.
We hope that helps answer the question ‘What is What is a Brake Disc?’!

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