C/C composite material is carbon matrix reinforced by carbon fiber. The whole system is made up of carbon element. So the carbon structure which is formed by carbon element will have a big influence on the mechanical properties, thermal performance, friction and wear properties of the composite material.the degree of graphitization is one of the most important indexes to characterize the carbon carbon composite material.most researches show that the higher degree of graphitization which has a better combination properties to the carbon carbon composite material.
According to the different kinds of raw materials,the carbon fiber can be divided into three kinds: polyacrylonitrile base(PAN) fiber,pitch base fiber and rayon base fiber. Generally speaking,the PAN base fiber is harder to be graphitization than pitch base,the rayon base is easier to be graphitizatioin than ordinary pitch base fiber.the difficult degree of graphitization is affected by the presoma.
The technology of matrix carbon mainly includes pyrolytic carbon,resin carbon,pitch carbon, in general,the pitch carbon is easier to be graphitization,and the resin carbon is hard to be graphitization,the difficult degree of pyrolytic carbon is depanding on the different structure,the rough laminar is easiest to be graphitization,the smooth laminar is harder than the RL,and the isotropic is the most difficult to be graphitization of all.
Under the right temperature (>1600C0),the carbon will transform into the graphite,and the changing process will be finished until the temperature reach 3000C0.
The graphitization processing of carbon carbon composite material takes advantage of heating to activate the amorphous carbon into graphite,so the degree of graphitization is not only depanding on the material structure but the heating temperature,pressure,the time of atomic rearrangement.