Introduction to the application of friction materials
At present, asbestos materials are widely used as automotive brake pads. Although its carrying capacity is not as good as powder metallurgy materials, the friction coefficient is higher, and the dynamic and static friction coefficients are close, which can make the braking smooth, the noise is small, and the price is low.
Powder metallurgy friction materials are used in almost all fields except automotive. It can work normally under high load and high temperature, especially known for stable friction coefficient and good wear resistance, so it is used as brake pads for aircraft landing, large-load ball screw friction pads and electric mechanism clutch pads.
In cars, ships, trains and other transportation machinery, in bulldozers, mine lifts, excavators and tractors and other large and medium-sized construction machinery and agricultural machinery, light industrial machinery, various specifications, types of powder metallurgy friction pads, brake pads in addition to excellent clutch, braking role, but also reduce energy consumption, improve transmission accuracy. With the development of modern science and technology, the demand for high-performance friction materials is more urgent.
The carbon-carbon composite material that appeared in the late 1970s is a very promising friction material, which has stable high-temperature friction performance, long life and light weight, and has been successfully used in the braking device of Concorde and Boeing aircraft, but the price is expensive, affecting the universality of application. Graphite based friction materials with good performance under moderate load, low temperature and wet friction conditions are also a promising new material. It has almost all the advantages of current asbestos and powder metallurgy materials, and the price is cheap, is an ideal friction material.
