Ti3Al基合金的拉伸形变和断裂

测试了三种显微组织Ｔｉ３Ａｌ基合金的室、高温拉伸性能；并用ＳＥＭ和ＴＥＭ详细观察样品的形变和断裂特征，结果发现，材料的力学性能与断口和位错组态的变化密切相关，随实验温度升高，强度降低，延性增加；随固溶温度提高，强度增加，延性降低，三种组织室温拉伸均为解理断裂，温度呈现解理与沿晶混合断裂。

TENSILE DEFORMATION AND FRACTURE OF Ti_3Al BASED ALLOY

The tensile properties of Ti3Al based alloy undergone 3 different regimes of solutioning treatment have been examined at room and elevated temperatures. The deformation and fractrure feature of the typical specimens have been observed under SEM and TEM. It is found that the mechanical properties correlated closely with the changes of fracture surface and dislocation configuration. With increasing testing temperature the strength decreased and the ductility increased. but with increasing solution temperature the strength increased and the ductility decreased. The cleavage fracture is revealed at room temperature in the three microstructures and the mixed (cleavage and intergranular) fractrue at elevated temperature.