Function: The brake disc acts as a braking surface, creating friction with four brake pads when you step on the brake pedal. Friction between the brake disc and brake brick creates resistance, slowing or stopping the vehicle.Materials: Brake discs are typically made from cast iron or carbon steel, with carbon steel being the most common choice. Premium brake discs can be made from steel alloys or carbon ceramic, for improved performance and durability.Structure: Brake discs usually have one or two screws or ventilation ports in the center, which help cool and remove heat from the braking process. It may have grooves or vents to enhance heat dissipation and remove dust and grease from the braking surface.Maintenance and repair: Brake discs need to be periodically maintained and regularly inspected to ensure the safety and performance of the braking system. When the brake disc is worn or deformed due to high temperature, it should be replaced immediately to avoid causing problems when braking.