Improvement in oxidation resistance of TiAl alloys by in-situ precipitation of Ti2AlC at the interface of α2 and γ lamellae

Herein, in-situ sintered micro-nano Ti2AlC/TiAl composite with fully lamellar structures were designed by spark plasma sintering to improve the high-temperature oxidation resistance of TiAl alloys. The Ti2AlC/TiAl composite exhibited lower oxidation rate and thinner oxide scale enriched Al2O3 compared to TiAl alloy after 750 ℃ and 850 ℃ oxidation, suggesting that oxidation resistance of the Ti2AlC/TiAl composite was improved. The superior oxidation resistance of the Ti2AlC/TiAl composite was mainly attributed to Ti2AlC particles hindered the diffusion of O atoms and stabilized the Al-rich oxide layer by the formation of more Ti-Al-N layers due to the nitridation susceptibility of Ti2AlC.