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采用金相显微镜、扫描电镜和透射电镜，对超塑性拉伸变形后的Ti－33Al－3Cr－0．5Mo（质量分数）合金的显微组织进行了观察和分析。研究发现，TiAl基合金在超塑性变形过程中发生了动态再结晶现象，动态再结晶使晶粒显著细化。透射电镜观察结果表明，γ晶粒内有位错运动．位错运动导致γ晶粒内形成位错墙、位错网。这些显微组织特征与TiAl基合金的超塑性变形机理有着密切的关系。
The microstructure of Ti-33Al-3Cr-0.5Mo (mass fraction) alloy after superplastic tensile deformation was observed and analyzed by optical microscope, scanning electron microscope and transmission electron microscope. The results show that dynamic recrystallization occurs during the superplastic deformation of TiAl-based alloy, and the dynamic recrystallization makes the grain refinement remarkably. Transmission electron microscopy showed that there was dislocation motion in γ grains. Dislocation motion results in the formation of dislocation walls and dislocation networks within the gamma grains. These microstructures are closely related to the superplastic deformation mechanism of TiAl-based alloys.