SiC/Si - MoSi2/MoSi2 oxidation protective coating for carbon material at 1700 °C

A multi-layer coating SiC/ Si - MoSi2 /MoSi2 with good oxidation resistance has been developed by using the slurry-sintering method on the surface of graphite to improve the oxidation resistance performance at 1700 degrees C for more than 200 h. Microstructure and anti-oxidation property of the as-received coating were investigated. It was found that functionally gradient SiC/ Si - MoSi2 /MoSi2 coating was formed on the surface of the graphite substrate. The coating characterized by excellent thermal shock resistance can effectively protect the graphite from oxidation at 1700 degrees C for 200 h. The mechanism of the oxidation resistance of the coated graphite is also dicussed, and a dense SiO2 layer was formed on the surface of coating at 1700 degrees C during the isotheral oxidation, which can protect graphite from oxidation at longer time.