Explanation

The materials made of composition with carbon or graphite fiber as reinforcement and carbon or graphite as matrix is also called carbon fiber reinforced carbon matrix composites. It was developed in 1958 and can be divided into organic polymerization pyrolysis method method and chemical vapor impregnation method according to the manufacturing process. Weave carbon fibers into the required preforms in a unidirectional, bidirectional, or multi-directional manner. The pyrolysis method of organic polymer is to repeatedly soak the fiber preform of organic polymer, such as phenolic resin, pyrolyze it into carbon, and convert matrix carbon into graphite at high temperature. The chemical vapor impregnation method is to infiltrate the vapor phase carbon into the fiber and the molding body to form pyrolytic graphite and obtain composite materials. The manufacturing process is complex, the cycle is long, and the cost is high, but it has good mechanical properties, high strength, good rigidity, low density, wear resistance, and good thermal conductivity. Used in an inert atmosphere, it has good thermal and chemical stability and can be used for over 2000t. The antioxidant performance is poor, and its performance severely decreases at around 600 ° C in an oxidizing atmosphere. When used in oxidizing atmosphere, coating protection shall be adopted, and one or more layers of protective films shall be coated on the surface of composite materials or carbon fiber to improve the high temperature resistance. The protective layer generally adopts refractory compounds, such as carbide, quartze, etc. It is widely used for nose cone caps, surface layers, nozzles, wings, etc. of intercontinental missiles, rockets and space shuttles, brake pads of hypersonic aircraft and racing cars, thermal components of high-temperature engines, biomedical materials, etc.

Classification