[Chen, Xiaoqun ; He, Yuehui ; Huang, Baiyun ; Qu, Xuanhui ; Lei, Changhui ] Powder Metallurgy Research Institute, Ctrl. South University of Technology, Changsha 410083, China
The microstructure and mechanical properties of a titanium aluminide alloy, Ti-33Al-3Cr-0.5Mo, under a multi-step thermo-mechanical treatment were studied. A sub-duplex microstructure with fine equiaxial γgrains as the major phase and β<sub>2</sub>, α<sub>2</sub> as the minor phases was obtained after final heat treatment at 1250°C, for 4 h + controlled cooling. Tensile elongation for the alloy can reach 5.07% at room temperature. The principal reasons for improving elongation are the refine of grain and improvment of grain boundary structure.