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研究了拉伸过程中，ＮｉＴｉ形状记忆合金丝的应变与电阻的关系．结果表明，对于初始组织为马氏体的ＮｉＴｉ丝，在拉伸过程中，电阻与应变之间成线性关系．对于初始组织为奥氏体或奥氏马氏体两者混合的ＮｉＴｉ丝，当发生应力诱发马氏体相变后，曲线的斜率降低，相变前后电阻－应变保持线性关系．对于初始组织含有Ｒ相组织的ＮｉＴｉ丝，在拉伸过程中，电阻的变化规律较为复杂，取决于初始组织中各相的比例和温度．在卸载阶段，当没有相变过程发生时，电阻－应变之间呈线性关系；当有相变过程发生时，电阻－应变曲线的斜率会发生改变．
The relationship between strain and resistance of NiTi shape memory alloy wire during drawing process was studied. The results show that for the NiTi wire with martensite initial structure, there is a linear relationship between resistance and strain during the drawing process. For the NiTi wire with initial microstructure mixed with austenite or austenitic martensite, the slope of the curve decreases after stress-induced martensitic transformation, and the resistance-strain maintains a linear relationship before and after phase transformation. For the NiTi wire with R phase structure in the initial structure, the variation of the resistance during the drawing process is more complicated, which depends on the proportion and temperature of each phase in the initial structure. During the unloading phase, there is a linear relationship between resistance and strain when no phase change occurs, and the slope of the resistance-strain curve changes when a phase change occurs.