Effect of SiC on the antioxidant properties of Al-containing composites Ti3SiC2/SiC and its oxidation mechanism analysis

Abstract

This study aims at improving the oxidation resistance of ceramics intended for high-temperature applications by examining the quantitative SiC-reinforced aluminum-containing composites Ti₃SiC₂/SiC that were synthesized through a powder metallurgy method. The high-temperature antioxidant properties of these composites were evaluated at temperatures between 900 °C and 1300 °C. The findings reveal that an increase in SiC content elevates the activation energy associated with oxidation, mitigates oxidation behavior, and decreases the weight gain attributable to oxidation of the material. Additionally, the formation of the oxide layer and atomic diffusion were investigated through the analysis of surface micro-morphology and the distribution of the oxide layer at the interface. It was found that the addition of SiC modifies the oxide layer structure of the material, which primarily consists of an outer mixed oxide layer of TiO₂ and Al₂O₃, an intermediate oxide layer of TiO₂ with a small amount of SiO₂, and an inner homogeneous mixed oxide layer of TiO₂ and SiO₂. Finally, the high-temperature oxidation mechanism of Ti₃SiC₂/SiC composites is systematically illustrated through experimental results.