Before the 1970s, brake pads contained a large amount of asbestos material, which has the characteristics of high temperature resistance, fire resistance, and strong friction. However, due to the various harms caused by the powder generated during the production and use of asbestos to the human body, it can easily lead to respiratory diseases and even cancer. Therefore, asbestos brake pads have been banned worldwide.

Half metallic brake pads are mainly composed of 30% -65% metallic materials such as copper and iron. The characteristics of this type of brake pad are fast heat dissipation, good high-temperature resistance, and relatively low price. However, due to the presence of metal materials, there is a significant amount of noise generated during braking, and the wear on the brake discs is also significant. In addition, the friction coefficient of these brake pads is generally 0.38, and their service life is relatively short.