Steam oxidation of silicon carbide at temperatures above 1600C

Pham, V. H.   ; Nagae, Yuji ; Kurata, Masaki 

High temperature interaction of chemical vapor deposition SiC with steam was investigated at 1700-1800C for 0.1-3 h in a mixture of steam and argon gas containing 98% of steam at 1 atm. At the investigated conditions, although a dense oxide layer was observed on sample surface, significant mass loss of SiC occurred. Below 1700C, the oxidation kinetics seems to follow the para-linear laws. The apparent activation calculated based on the data of this study is to be 370 kJ/mol. Rapid degradation and bubbling of SiC at 1800C were observed after 1 h oxidation. This suggested that chemical interaction behaviours above 1700C might be changed due to the liquefaction of silica.