Generally divided into binder, fiber, friction modifier, filler four major parts:Binder is one of the most important components in the friction material, it can affect the material thermal decay performance, recovery performance, wear performance and mechanical properties. Generally thermosetting, thermoplastic, rubber, composite type of several types of automotive friction materials are generally used in the thermal curing adhesive, the specific application of phenolic resin, melamine resin, epoxy resin, silicone resin, polyamide resin Wait. The most widely used are phenolic resin and its modified resin. The purpose of modification is to improve the high temperature properties of the resin. In order to greatly improve the high-temperature performance of the adhesive, advanced automobile friction materials have been used in some polyimide resins, but at present the cost of such resins is too high and the popularity is not easy.
Reinforcing fiber is a friction material and the main friction component plays a role as a reinforcing base. As traditional materials, asbestos and other mineral fibers are used. Semi-metallic automotive friction materials are made of steel fibers, while a small amount of copper fibers and a few mineral fibers are added. In recent years, there are more and more types of reinforcing fibers, of which Kevlar is the most attractive. The addition of organic fibers can reduce the density of the material and reduce its wear, but also reduce the friction coefficient of the material. In order to improve the stability of the friction material at various temperatures and the affinity of the fibers and binders, a variety of fibers are often used in practical applications.
Frictional performance regulators can be divided into two categories: (1) Anti-friction material: Mohs hardness is generally less than 2, its addition can improve the material's abrasion resistance, reduce noise and reduce the friction coefficient. Such materials are: graphite, molybdenum disulfide, lead, copper and so on. (2) friction material: Mohs hardness is generally greater than 4, it can increase the friction coefficient of the material. Most inorganic fillers and some metals and their oxides belong to this category. Frictional performance modifier is added mainly to adjust the thermal stability of materials and their work stability. The filler is added mainly in the form of a powder. The role of a lot of filler, for example, by adding copper powder, its role is to form a transfer film between the friction material and dual, both to improve the friction torque and stable friction coefficient, can reduce the damage to the counterparts, improve the friction pair The resistance to friction. By adding barium sulfate, can increase the density of the material.