显微组织对 Ti_3Al 基金属间化合物拉伸性能的影响

Influence of Microstructure on Tensile Properties of Intermetallic Compound Based Ti 3Al

对三种显微组织Ｔｉ３Ａｌ基金属间化合物在室、高温拉伸试验，用ＳＥＭ和ＴＥＭ观察试样的形变和断裂特征，并用微机处理实验数据，发现：材料的力学性能与断口和位错组态的变化密切相关．随固溶温度提高，强度增加，延性降低；随实验温度升高，强度降低，延性增加．三种组织室温拉伸均为解理断裂，高温呈解理与沿晶混合断裂．

The tensile properties of intermetalli compound based Ti 3Al undergone 3 different regimes of solutioning treatment were examind at room and elevated temperatures. The deformation and fracture of the tyoical speciments were 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 temperatur in the three microstructures and the mixed(cleavage and intergranular)fracture at elevated temperature.