Al2O3 reinforced MoAlB ceramic with improved oxidation resistance

Abstract

Oxidation behaviors of Al₂O₃ reinforced MoAlB ceramics prepared by spark plasma sintering were investigated at 800–1200 °C. The results revealed that appropriate addition of Al₂O₃ facilitated the improvement of oxidation resistance and mechanical properties of MoAlB ceramics. Among them, the composite ceramics with 5 vol% Al₂O₃ addition possessed reinforced antioxidant properties with the oxide layer thickness being only 1.81 µm for 800 °C and 2.08 µm for 1000 °C after oxidation for 64 h, respectively. MoAlB ceramics added with 10 vol% Al₂O₃ demonstrated the optimal mechanical properties. However, excessive addition of Al₂O₃ adversely affected both the antioxidant and mechanical properties.