Enhancing the mechanical properties of high Nb-TiAl composites by addition of nano-Y2O3 via induction hot-pressing sintering

Induction sintering as a rapid sintering method has been seldom investigated and reported in the TiAl alloys. In this paper, the induction hot-pressing sintering was used to synthesize Ti-47.7Al-7.1Nb-(V, Cr)+ xY2O3 (x = 0.05, 0.1, and 0.2 at%) composites and the influence of Y2O3 content and sintering parameters on phases composition, microstructure evolution, and mechanical properties were systematically investigated. The results showed that the lamellar colonies were significantly refined with the 0.05 at% nano-Y2O3 addition (decreasing from 280 +/- 145 mu m to 50 +/- 25 mu m), and the Y2O3 particles displayed in the TiAl matrix were mainly nanometer-sized. The room-temperature and high-temperature mechanical properties were both improved due to the refinement of the lamellar colonies and the second particle acting as an obstacle to dislocation motion.