Why does the brake pad draw a groove on the plate?

Update:13-12-2018
Summary:

The main body of the brake pad is generally divided int […]

The main body of the brake pad is generally divided into two parts: the friction layer and the steel back. The main difference between the quality of the brake pad is the friction layer, the friction layer is a composite material, and the mixture is composed of organic fiber, inorganic fiber, mineral filler, phenolic resin, etc. The composition is subjected to high temperature and high pressure and hot press forming. Many brake pads now divide the friction layer into two layers, the bottom material and the top layer material. The bottom material is in the middle of the steel back and the top layer. During the use of the brake pad, the surface material is first worn away, and then It will wear to the underlying material and then wear to the steel back. Generally, the brake pads should be replaced before the finish is worn.

The brake pad itself causes the brake disc to be scratched. The brake pad top layer contains mineral fibers. The mineral fibers are melted by various minerals at high temperatures and then spun to form fibers. However, while the fibers are produced during the spinning process, some are not sprayed into fibers, and some form small balls (referred to as "slag balls"). These balls have a much higher hardness than fibrous ores. It can cause problems with the brake disc. After the production of mineral fibers, the content of slag balls will be as high as 40% to 50%, and large brands will be screened. The purity of the mineral fiber will be increased to about 95% to 98.5%. However, it still contains 1.5% to 5% of the slag balls (the current process cannot remove all the slag balls). Mineral fibers used in general lining fabric layers are of this type. Inevitably, it will contain a small amount of slag balls. Damage to the brake disc. If the fabric layer of the brake pad contains too much slag ball, the brake disc will be drawn out of the groove. If the situation is serious, the brake pad and the brake disc need to be replaced together.