Brake pads are car brake linings, which are friction materials fixed on the brake drum or brake disc that rotates with the wheels. The friction linings and friction pads are subjected to external pressure to produce friction effects to achieve vehicle deceleration or stop. Therefore, the brake pads are a vital part of the car and are related to personal safety. So what are the brake pads made of?
* Steel back
* Bonding layer
* Bottom cushion material
* Friction material
* Shim
* Spray paint coating
* Slotting
* Chamfering
* Spray coding
* Other attachments
The Main Performance of Brake Pads
The performance of the same brake pad under different temperatures, different vehicle speeds, and different braking pressures is very different.
1. Braking performance: refers to the braking ability (friction coefficient) of the brake pads under the normal braking state (the braking temperature is relatively low).
2. Decay performance: In the road conditions such as downhill mountain roads, the brakes brake continuously and the temperature rises rapidly, and the brake disc may reach a temperature of 4, 500 or even 700 degrees Celsius. The braking capacity of the brake pads will become worse and the braking distance will increase. This phenomenon is called "recession", and we certainly hope that the smaller the recession rate, the better. The decline rate of high-quality brake pads is very small, and some even do not decline, while some fake and inferior products decline very seriously, and almost lose their braking ability at high temperatures.
3. Recovery performance: After the high temperature decayed brake pads, when the temperature drops, can the original braking performance be restored as soon as possible? This is also the importance of measuring the quality of brake pads
4. Brake pad wear: It is the wear of the brake pads when they are used. The braking effect depends on the formula and process of the friction material. For example, carbon fiber brake pads can be used for hundreds of thousands of kilometers without replacement. In addition to the wear of the brake itself, the wear of the brake pads should also be considered. During the braking process, the high-quality brake pads will form a protective film on the friction surface of the brake disc to reduce the wear of the brake disc, while the inferior brake pads contain a lot of hard points and impurities, which will pull out many grooves on the surface of the brake disc. , accelerate the wear of brake pads and brake discs.
5. Noise is also a very important indicator in today's advocating environmental protection. In fact, there are many factors that cause braking noise, and brake pads are only one of them. It is generally believed that if the hardness of the brake pads is too high, it is easy to generate noise.
6. Other performance indicators such as shear strength, hardness, compressibility, thermal expansion, water absorption, adhesion, etc.
About Service Life of Brake Pads
There is no definite statement, different cars, different car habits and road conditions have different wear on the brake pads.
Generally, the frequency of replacing the brake pads of a car is about 30,000 kilometers. If the brakes are not too hard, the brake pads can run for an additional 10,000 kilometers. Basically, they need to be checked at 30,000 kilometers.
If there are no brake pads, it is very dangerous. Now most cars basically have brake pad warning lights. If the brake pads are worn out, the instrument light will give an alarm. If there is no warning light for low-end models, the brake pads can be in the gap of the wheel hub. See how thick the friction is.
If the car has not worn out after 70,000-80,000 kilometers, the brake pads are too hard, which is not good for the brake disc. It is recommended to replace the brake pads.
