Ｓ本文研究了层片状双相ＴｉＡｌ合金的室温拉伸压缩变形行为与断裂行为，发现在拉压变形条件下，其室温塑性有显著差异．并且这种差异与裂纹扩展路径有关．在室温拉伸与压缩变形时，该合金的拉压屈服应力随外载与层片界面间的夹角ψ的变化趋势一致，而拉压断裂应变εｆ随夹角ψ的变化趋势正好相反．外载与层片界面垂直时（ψ＝９０°），拉伸断裂应变最小（εｆ≈０）；压缩断裂应变最大（εｆ≈３８％）．夹角ψ减小时，拉伸断裂应变增加，压缩断裂应变减小在拉、压变形时裂纹的扩展路径不同。 S In this paper, tensile and compressive deformation behavior and fracture behavior of lamellar double-phase TiAl alloy at room temperature were studied. It was found that under tensile and compressive deformation conditions, the plasticity at room temperature was significantly different. And this difference is related to the crack propagation path. At room temperature tensile and compressive deformation, the tension-compression yield stress of the alloy is consistent with the change of the included angle ψ between the external load and the interface of the ply, while the tensile strain εf changes with the angle ψ. When the external load is perpendicular to the ply interface (ψ = 90 °), the tensile strain at break is the smallest (εf ≈ 0) and the compressive strain at fracture is the highest (εf ≈ 38%). When the included angle ψ decreases, the strain at tensile fracture increases and the strain at compression fracture decreases. The propagation path of the crack at the time of tension and compression deformation is different.