The carbon carbon composite materials as excellent thermal structure, functional integration of Engineering materials, since its birth in 1958, it has been greatly developed in the military , the most important use is for the manufacture of missile warhead components. Due to its high temperature resistance, good wear. It has been widely used in solid rocket motor, aerospace structural parts of aircraft, aircraft and racing brake device, the heating element and mechanical fasteners, heat exchanger, aviation engine hot end components.
The properties of carbon carbon composites:
(1) The physical properties: the C / C composites after heat treatment in the chemical composition and elemental carbon higher than 99%, low density, has a strong affinity, due to the high melting point of elemental carbon, it has high temperature resistance, good corrosion resistance and thermal shock resistance, acid, alkali, salt.
(2) The mechanical properties: The strength, modulus of elasticity and friction and wear resistance performances are the mechanical properties of C/C composites.
(3)The high temperature stability: the room temperature strength of C/C composite can be maintained to 2500 C, the thermal stress of C/C composites is not sensitive, it has good resistance to erosion.
(4) The comprehensive performance evaluation: the strength and elastic modulus of C/C composite at room temperature is good, the production of C/C composite material is less, it can save material and manufacturing cost, it has high safety and reliability.
The research results show that the major factors which influences the thermal conductivity of carbon / carbon composites is the the microstructure of CVD pyrolytic carbon , in different CVD pyrolytic carbon , the CVD pyrolytic carbon which the main structure is the RL structure has the highest thermal conductivity; whether heat treatment of carbon / carbon composites thermal conductivity rate has considerable influence, but the heat treatment temperature increasing of carbon / carbon composite thermal conductivity is limited to improve.
The properties of carbon carbon composite not only has high specific strength, high specific modulus and other prominent structural material characteristics, but also has excellent friction and wear and thermal physical properties, it can well meet the high-speed jet aircraft brake materials. The carbon / carbon composite materials has become a new generation of prospects for the development of aeronautical materials. The air brake carbon / carbon composites on the microstructure is a heterogeneous mixture