Carbon fiber brake pad principles and performance characteristics
Carbon fiber brake pads are friction products made by turning carbon fiber into a new material containing resin through high temperature and high pressure. It makes full use of the excellent physical properties of carbon fiber. Especially for carbon fiber composite friction materials, the coefficient of dynamic friction is greater than the coefficient of static friction. Carbon fiber brake pads have the following characteristics:
(1) The density is small. The density of carbon fiber brake pads is about 1.8g/cm3, which is only 1/3 to 1/4 of that of metal matrix composites. Brake pads made from carbon fiber mean they are lighter. For high-end cars and trains, this can not only increase the payload of the car, but also reduce weight and save fuel. Therefore, its cost-saving effect is very significant.
(2) Good braking performance. Brake pads made of carbon fiber have a smooth braking curve and can also withstand more thermal shock from braking friction.
(3) Low wear rate. The results show that under dry grinding conditions, if the relative wear of steel/carbon fiber composites is 1, the wear of carbon fiber composites/steel is 10, while the wear of steel/steel composites is 5000. Therefore, the wear resistance of carbon fiber brake pads and the wear of friction couple materials are lower than that of steel fiber brake pads, which not only extends the life of the brake pads, but also reduces the number of repairs of the brake pad components.
(4) Low braking noise. The current brake pads produce a harsh noise when braking, especially when braking at high speeds. The loss factor of the sound wave vibration attenuation of carbon fiber is 0.024±0.008, which is in the buffer state during the braking process without any noise.
Outstanding environmental resistance. No matter in a humid or acidic environment, carbon fiber brake pads are not prone to corrosion and rust problems, and their mechanical properties will not decay. Therefore, the corrosion resistance of carbon fiber brake pads is better than that of semi-metallic materials.
