以NiTi合金为研究对象,在万能试验机上采用原位拉伸方法研究其马氏体相变的失稳情况。结果表明,NiTi合金马氏体形核时的应力应变曲线具有非线性变化特征。马氏体合并时,相变潜热增加了马氏体的形核功。马氏体分裂时,应力波动值较低。 Taking NiTi alloy as the research object, the instability of martensitic transformation was investigated by in-situ tensile test on a universal testing machine. The results show that the stress-strain curve of NiTi alloy martensitic nuclei has a nonlinear variation. When martensite is combined, the latent heat of phase transformation increases martensite nucleation work. When martensite splits, the value of stress fluctuation is low.