Friction material is a kind of polymer ternary composite material, which is a chemical and physical complex. It is composed of polymer binder (rubber and resin), friction performance regulator, reinforced fiber and other additives. It is a series of products manufactured through a series of production and processing.
Friction materials have good wear resistance and friction coefficient. At the same time, it also has certain mechanical strength and heat resistance, which can meet the performance requirements of vehicle or mechanical braking and transmission. Friction materials are widely used in various kinds of construction machinery and equipment, such as automobiles, trains, airplanes, oil rigs, etc., and are indispensable materials for power transmission or braking deceleration of civil products such as washing machines and bicycles.
Friction materials are used as functional accessories in many sports machinery and equipment to play the role of transmission, braking, deceleration, steering, parking and so on. According to the function and installation position, it is mainly divided into brake lining and clutch plate. In the automotive industry, friction materials are the key safety components. The starting, braking and parking of vehicles are inseparable from friction materials. The quality of friction materials is directly related to the safety of people's life and property, and its function and status are self-evident.
In modern society, the requirement of environmental protection and safety is higher and higher. The developed countries of automobile industry in the world have rapidly launched the research and development of non asbestos friction materials. They have successively launched non asbestos semi-metallic friction materials, sintered metal friction materials, alternative fiber reinforced or polymer bonded friction materials, composite fiber friction materials, ceramic fiber friction materials, etc.
These new friction materials have the following common characteristics:
（1） The composition of metal is added to improve the service humidity and service life of friction materials;
（2） All of them do not contain asbestos, instead, substitute fibers or polymers are used as reinforcement materials;
（3） A variety of additives or fillers are added to reduce braking noise and chatter, and to optimize friction stability and anti adhesion.
High temperature resistance, wear resistance, increase toughness, increase friction coefficient, reduce brake noise, make product performance stable. The requirement of MgO content in clutch plate is high. Both heavy magnesium oxide and light magnesium oxide can be used. The addition amount of heavy magnesium oxide is larger, while that of light magnesium oxide is smaller. The products produced by using light magnesium oxide are more stable, better quality and higher qualified rate.