采用金相显微镜、X射线衍射(XRD)、透射电镜(TEM)、示差扫描量热分析(DSC)和力学压缩实验系统研究了Ti69Zr30Fe1高温形状记忆合金的微观结构、相变行为和力学性能.结果表明,Ti69Zr30Fe1合金室温下为单一的针状α”马氏体相(正交结构)孪晶.在加热过程中,合金在580℃左右首先析出纳米尺度的ω相,然后在615℃到633℃之间发生从α”马氏体相到β相的逆相变.冷却时在584℃到529℃之间发生马氏体相变.合金室温压缩临界应力为550 MPa,最大形状记忆效应达到2.1%.
The microstructure,phase transformation and shape memory properties of Ti69Zr30Fe1 high-temperature shape memory alloy were investigated by optical microscopy (OM),X-ray diffraction (XRD),transmission electron microscopy (TEM),differential scanning calorimetry (DSC) and compressive tests.The results show that Ti69Zr30Fe1 alloy is composed of single needle-like α" martensite with orthorhombic structure at room temperature.During heating process,nano scale ω phases precipitate within the grains at 584 ℃,and then reverse martensitic transformation from α" phase to β phase occurs at 615~633 ℃.When cooling,martensitic transformation occurs from 584 to 529 ℃.The critical stress of Ti69Zr30Fe1 alloy is about 550 MPa and the maximum shape memory effect (SME) is 2.1%.