Detailed interpretation of brake friction materials (2)
NAO (Asbestos-Free Organic Material)
Materials used
Asbestos-free organic brake materials mainly use glass fiber, aromatic polycool fiber or other fibers (carbon, ceramics, etc.) as reinforcement materials, and their performance mainly depends on the type of fiber and other additives.
The main advantage
In the case of ensuring a reasonable brake size matching, the wear of the NAO friction plate itself and the wear of the brake disc are relatively low. Of course, the problem of brake dust will also be greatly reduced. The friction coefficient of NAO is relatively low in most cases. , so the chance of brake noise is also greatly reduced.
Low metal friction material
Materials used
Low-metal friction material is an improved friction material aimed at the problems of "semi-metal" mixture friction material.
The main advantage
Low-metal friction materials are generally higher than NAO in terms of friction performance output; in terms of thermal stability, it mainly refers to the problem of brake vibration caused by thermal recession and continuous braking, because low-metal friction plates contain more iron components, iron resistance The thermal temperature is higher, and the thermal conductivity is better, so the low metal friction plate has more advantages in thermal recession resistance.
main disadvantage
Low-metal materials generally have a relatively large friction coefficient. When the friction coefficient is greater than 0.36, the probability of brake noise will also increase greatly. Such friction materials are usually based on specific noise frequencies in solving the problem of brake noise, and the sound-absorbing plates are selected to eliminate noise in a more targeted manner.
There is no best formula, only suitable or not, no one friction material formula is suitable for all models. There is also no friction material formula that can achieve the ultimate in various data. It will only make choices based on the weight of the vehicle, engine displacement, maximum speed, brake disc material, driving conditions, and economic applicability. Therefore, the brake friction materials selected by each model and even the car series are different.
