Oxidation behavior of Al2O3 added reaction-sintered SiC ceramics in wet oxygen environment at 1300°C

Abstract

The oxidation behavior of reaction-bonded SiC ceramics with Al2O3 was investigated at 1300°C for exposure duration up to 100 h under water vapor environment. Results show that Al2O3 is enriched on the oxidation surface, reducing the volatilization of the oxide layer and preventing the reduction of macroscopic size. Raman spectra results further testified that Al2O3 obviously improves the stability of glass structure and reduces the generation of non-bridged oxygen atoms (Si–O–H), which results in a lower reaction activity with steam of the aluminosilicate melt, therefore, significantly improving the oxidation resistance of SiC in O2/H2O atmosphere.

Keywords

• SiC ceramics
• water vapor
• aluminosilicates