采用非自耗真空电弧熔炼Ti-45Al-5Nb-xMo-0.3Y(x=0.6,0.8,1.0,1.2)合金试样,研究Mo含量变化对含β相TiAl合金显微组织和力学性能的影响规律。研究表明,Mo元素的偏聚使β相呈不连续网状分布于γ/α_2片层团边界。当Mo含量超过0.8%时,β相在枝晶间微偏析区易形成γ相。在T_α转变温度以上进行均匀化热处理可使β和γ相得到有效消除。对初始铸态和均匀化热处理态TiAl合金的组织性能进行对比分析发现,添加过量的Mo元素容易引起微偏聚,从而降低材料的强度和显微硬度,而均匀化热处理可使得其力学性能得到明显改善。 Ti-45Al-5Nb-xMo-0.3Y (x = 0.6,0.8,1.0,1.2) alloy samples were fabricated by non-consumable vacuum arc melting to study the effect of Mo content on the microstructure and mechanical properties of Ti-containing TiAl alloys law. The results show that the segregation of Mo element makes the β phase discontinuous reticulate distribution at the γ / α 2 lamellar boundary. When the Mo content exceeds 0.8%, the β phase forms a γ phase easily in the interdendritic micro-segregation zone. The homogenization heat treatment above the T_α transformation temperature can effectively eliminate the β and γ phases. Comparative analysis of microstructures and properties of the as-cast and homogenized TiAl alloy shows that addition of excessive Mo can easily lead to micro-segregation, which can reduce the strength and microhardness of the material. The homogenization heat treatment can make the mechanical properties Significant improvement.