Oxidation behavior of γ-TiAl based alloy with Al2O3–Y2O3 composite coatings prepared by electrophoretic deposition

Electrophoretic deposition (EPD), a versatile and cost-effective process, was employed to prepare Al2O3–Y2O3 composite coatings on a γ-TiAl based alloy. SEM observations showed that the composite coatings were compact and consisted of uniform nano-particles. Cyclic oxidation at 1000 °C indicated that the γ-TiAl alloy exhibited a cyclic spallation–oxidation behavior under cyclic oxidation while the Al2O3–Y2O3 composite coatings improved the oxidation and scale spallation resistance of γ-TiAl alloy significantly due to the suppression of outward diffusion of Ti in the γ-TiAl substrate and the promotion of selective oxidation of Al in the γ-TiAl alloy induced by the composite coating.