Carbon carbon composite material has a series of advantages under the high thermal condition,and it’s widely used in the aerospace field,however,the material will be oxidized rapidly in the aerobic conditions when the tempterature above 400 centigrade,and it will limit the using as the structure parts,protection material etc. And the coating technology is the good method to solve this problem.
SiC,ZrC material,as they have high melting point and good stable property under high tempterature, so they become the ideal material of protecting coating of carbon carbon composite material.
It can use the low pressure chemical vapor deposition(LPCVD) method to make the SiC coating and ZrC coating on the surface of carbon fiber and the inside C/C composite material. The different methods of this two material can be devide into SiC/ZrC mixed coating and SiC/ZrC/SiC multilayer coating, and it can improve the ablation property of the coating.
The mixed SiC/ZrC coating and the SiC/ZrC/SiC multilayer can improve thermal expansion mismatch between the ZrC layer and the carbon carbon composite material matrix,increase the ablation property of the carbon carbon composite material coating.
Missile, manned spaceship, space shuttle etc,most aerocrafts velocity is faster than the light speed,the tempterature around the aerocrafts will increase rapidly, and the tempterature on the surface of nozzle , aerofoil will above 2000 centigrade,except for these effects,there is the high speed particle flow on the surface, the normal material is hardly to bear all this bad environment. So the lighter weight material,high strength material and high thermal resistance material is needed.
Carbon carbon composite material is reinforced by the carbon fiber, and it’s made of the single element(carbon),low density,high strength,high modulus and good ablation property etc.meanwhile,the C/C material can bear the high tempterature, under the high tempterature,the material can still maintain the good properties.