Simultaneous enhancement of strength and ductility in high Nb-TiAl by Si alloying

1.Introduction TiAl alloys are lightweight and high-temperature-resistant structural materials having applicability in automotive and aerospace applications owing to their low density and excellent high-temperature properties[1-3].High-Nb-containing TiAl(High Nb-TiAl)alloys are considered as a new generation of TiAl alloys for applications at higher service temperatures[4-6].Components of TiAl alloys that have achieved long-term stability in the industry are mainly manufactured by casting,which is the most economical method[7-9].However,the mechanical properties of these com-ponents are limited at room temperature(RT),significantly hinder-ing their broad applications[7,10-12].