Development of TiAl alloys with excellent mechanical properties and oxidation resistance

Mechanical and oxidation properties of newly-developed TiAl alloys were investigated. The TiAl alloys in this study were manufactured by casting and no further heat-treatment was conducted. In this study, Ti–(40–44)Al–(3,6)Nb–(W,Cr)–Si–C alloys were developed and the possibility of using them for turbine wheels in automobile engines was examined in comparison with commercial TiAl alloys. The new alloys developed in this study showed excellent tensile strength at room temperature and high temperature (900 °C) as well as good oxidation resistance at 900 °C compared to the commercial TiAl alloy. Moreover, the new alloys showed much better castability than the commercial TiAl alloy.