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

• Preparation of Ti 3 SiC 2 /SiC composites with different contents of SiC. • SiC reduces oxidation weight gain and increases oxidation activation energy. • SiC improves the structure of the oxide layer and increases oxidation resistance. • Atomic migration is an important factor in the formation of oxidized delamination. This study aims at improving the oxidation resistance of ceramics intended for high-temperature applications by examining the quantitative SiC-reinforced aluminum-containing composites Ti 3 SiC 2 /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 TiO 2 and Al 2 O 3 , an intermediate oxide layer of TiO 2 with a small amount of SiO 2 , and an inner homogeneous mixed oxide layer of TiO 2 and SiO 2 . Finally, the high-temperature oxidation mechanism of Ti 3 SiC 2 /SiC composites is systematically illustrated through experimental results.