Brake pad sticking is a complex problem and is usually caused by a variety of reasons:
◆ Ⅰ High temperature factor
Prolonged braking: In the case of prolonged or frequent emergency braking of the vehicle, a large amount of frictional heat will be generated between the brake pads and the brake disc (drum). When the temperature is too high, the material on the surface of the brake pads may soften or even melt partially. Once cooled, the softened or melted material may stick the pads to the disc (drum).
Poor Heat Dissipation: The design of the brake system to dissipate heat is also very important in preventing pad sticking. If the heat dissipation channels of the brake pads or discs (drums) are blocked, for example, covered by dust, oil or other foreign materials, the temperature of the brake pads can easily become too high, which in turn increases the risk of sticking.
◆ Ⅱ Material problems
Poor quality brake pads: Some low-quality brake pads may use substandard materials or additives in the manufacturing process. These materials may have abnormal chemical reactions under certain conditions such as high temperature and high humidity, leading to sticking on the surface of the brake pads.
Abnormal surface coating: Some brake pads are specially coated to improve braking performance or prevent corrosion. However, if the coating is not formulated properly or if the coating process is poor, the coating may cause problems during braking. For example, the coating decomposes at high temperatures and produces a sticky substance, which causes the brake pads to stick.
◆ Ⅲ Environmental factors
Wet environment: When the vehicle is in a wet environment, such as driving in rain for a long time or parked in a place with high humidity, the surface of the brake pads and brake discs (drums) are prone to rusting. Rust will increase the friction between the brake pads and the brake disc (drum) to a certain extent, and may cause the brake pads not to be able to return completely after braking, increasing the possibility of sticking.
Corrosive substances pollution: If the brake pads or brake discs (drums) come into contact with corrosive chemicals, such as snowmelt on the road, acidic and alkaline liquids, etc., these substances may corrode the surface of the brake pads and brake discs (drums), destroying their original structure and performance. Some of the compounds produced in the corrosion process may be sticky, which in turn triggers brake pad sticking.
◆ Ⅳ Mechanical failure
Brake Caliper Failure: Brake caliper is the key component to control the contact and separation of brake pads and brake disc (drum). If the piston of the brake caliper is stuck and cannot return to its normal position, the brake pads will remain in contact with the brake disc (drum). In this case, even if the vehicle stops braking, it is easy to cause the brake pads and the disc (drum) to stick together due to the constant pressure between them.
Return spring failure: In some drum brake systems, the return spring plays an important role in returning the brake pads to their initial position at the end of braking. If the return spring deteriorates, breaks or loses its elasticity, the pads will not return to their original position properly, increasing the risk of sticking to the drum.
