Oxidation behavior characteristics of an aluminized Ni-based single crystal superalloy CM186LC between 900 °C and 1100 °C in air

摘要

Oxidation behavior of an aluminized Ni-based single crystal superalloy CM186LC was performed between 900 °C and 1100 °C in air. The oxidation kinetics approximately followed a parabolic oxidation law at 900 °C and 1100 °C. The mass gains were significantly increased owing to the formation of θ-Al2O3 during initial oxidation stage. After 100 h oxidation, the mass gain rates were then decreased due to the transformation from 6-Al2O3 to α-Al2O3. The microstructures after 500 h oxidation at all temperatures generally consisted of scale, coating layer, interdiffusion zone (IDZ), substrate diffusion zone (SDZ) accompanied with the topologically close-packed (TCP) and substrate.