Oxidation behavior of chemically vapor‐deposited SiC in CO─CO2 atmospheres (0.1 MPa) was investigated using a thermogravimetric technique at temperatures from 1823 to 1923 K. Active or passive oxidation was observed depending on temperature and CO2/CO partial pressure ratio (Pco2/Pco). The critical Pco2/Pco value for the transition was 1O2 times as large as a theoretical value calculated from the Wagner model. In the passive oxidation above 1873 K, SiO2 bubbles were grown. The expansion and rupture of bubbles caused cyclic rapid mass gain and mass loss.
|Number of pages||4|
|Journal||Journal of the American Ceramic Society|
|Publication status||Published - 1994 Apr|