Abstract
Oxidation mechanism of TiB2 particle dispersed SiC (TiB2/SiC) was studied by microstructural analysis and the oxidation protection by using SiC-CVD coating was tested. The microstructural observation and element analysis by transmission electron microscope indicated that Ti existing at the grain boundary between TiB2 particle and SiC particle of TiB2/SiC was oxidized selectively at early oxidation stage. TiB2/SiC was suggested to be oxidized further because the oxidation products providing O2 diffusion path. The oxidation resistance of TiB2/SiC was successfully improved by SiC-CVD coating because the coating on TiB2/SiC was thought to restrain the O2 diffusion by the formation of thin SiO2 layer, the oxidation product of SiC-CVD coating
