Abstract:The influence of microstructures on the cyclic oxidation behaviour of Ti-33Al-3Cr-0.5 Mo(%) alloy was investigated. It was clarified that the oxidation behaviour of the alloy with near-gamma, duplex and fully-lamellar microstructure are very similiar in air at 1 173K and their mass gain is much lower than that of the alloy with nearly-lamellar microstructure. The reason for the difference in oxidation behaviours was attributed to the morphologies of Al₂O₃ layer in the oxide scale.

Key words: γ-TiAl oxidation microstructure morphology Al₂O₃ oxide scale