INFLUENCE OF OXIDATION TREATMENT ON THE PERFORMANCE OF C/C COMPOSITES USING MESOCARBON MICROBEADS AS MATRIX

C/C composites using mesocarbon microbeads (MCMB) as matrix and pitch based carbon fibers (CF) as reinforcement were prepared through simple oxidation treatment,mechanical blend,hot press molding and carbonization. The influences of oxidation treatments of MCMB and carbon fiber on the properties of C/C composites such as bulk density,volume shrinkage and bending strength were investigated in detail. It was found that the bulk density and volume shrinkage of C/C composites declined after adding CF, while the bending strength increased when CF was oxidized under appropriate conditions. High strength C/C composite with a density of 1.64 g/cm³ and bending strength of 72.0 MPa was obtained by hot press molding and carbonization at 1000℃ for 1h from MCMB oxidized at 250℃ in air for 60min and CF treated in nitric acid for 10h. This novel and simple approach constituted a more practical method to prepare high performance C/C composites than the present ones.