What are the common problems of brake pads?
How does the coefficient of friction affect braking?
Brake pads with such a low or high coefficient of friction will impact the car's braking performance. Especially when the car needs emergency braking while driving on the expressway, the friction coefficient is so high that the brakes will not be sharp, and the friction coefficient is so low that the tires will lock up, which will cause the vehicle to flick and blow out. Driving safety constitutes a serious threat. According to the national standard, the suitable working temperature of friction plate is 100～350℃. However, when the temperature of many low-quality friction plates reaches 250°C, the friction coefficient will drop sharply, so the brakes will completely fail at this time. Generally speaking, according to the SAE standard, the friction plate manufacturers will use the FF rating coefficient, that is, the friction rating coefficient is 0.35~0.45.
What is the relationship between the life of the friction plate and the hardness?
The life of the friction plate has no certain relationship with the surface hardness. However, if the surface hardness is high, the actual contact area between the friction plate and the brake disc is large, which often affects the service life. Therefore, the main factors affecting the life of the friction plate include hardness, strength, and abrasiveness of the friction material. Under normal circumstances, the service life of the front friction plate is 30,000 km, and the service life of the rear friction plate is 120,000 km.
Why does the vibration occur when braking?
It is often caused by the deformation of the friction lining or the brake disc, which is related to the material, processing accuracy and heating deformation of the friction lining and the brake disc. The main reasons are that the thickness of the brake disc is not uniform, the brake drum Less roundness, non-uniform damage of the friction plate, thermal deformation and hot spots, etc. In addition, the deformation or improper installation of the brake calipers, and the uneven friction coefficient of the friction plate will also cause vibration during braking. In addition, if the vibration frequency caused by the friction plate during braking and the suspension system resonate, it will also cause jitter.
