THE INFLUENCE OF OXIDATIVE TREATMENT ON THE PERFORMANCE OF CARBON BLOCKS FROM SELF-SINTERING PITCH-BASED MESOCARBON MICROBEADS

High strength isotropic carbon with a density of 1.64?g/cm3 and bend strength of 99.5?MPa was obtained from Mesocarbon Microbeads (MCMB). The process involves oxidation of MCMB at 300?℃ in air for 45?min by hot press molding and carbonization at 1?000?℃ for 1?h. The influences of oxidation temperature and time on the properties of carbonized blocks such as bulk density, volume shrinkage and bend strength were investigated, and the surface morphologies of the blocks were observed using scanning electron microscopy. Elemental analysis and Xray photoelectron spectroscopy measurements indicated that the oxygen content of the MCMB increased with the oxidation time, and was present in the form of hydroxyl, carbonyl and carboxyl groups, which increased the degree of crosslinkage of molecules in the MCMB and thus decreased the fluidity of MCMB during pressing and further heat treatment.