It is shown that in alloys with thermoelastic martensitic transformations, shape memory and superelasticity effects, the real yield stress (τ_0.3) can be determined only by a joint analysis of “stress-total strain” and “plastic deformation-total strain” dependences. We suggest to determine of the dependence of the “plastic deformation – total deformation” from isothermal cycles of “loading at successively increasing values of the applied external stress – unloading” and the subsequent heating of unloaded specimens up to finish of the return of inelastic martensitic deformation. The residual deformation equals to the plastic deformation in this case. Using Ti_49.2Ni_50.8 (at%) binary alloy specimens whose structure was changed from coarse-grained to micro- and submicrocrystalline by means of warm rolling, the yield point τ_0.3 in torsion of specimens was demonstrated to be localized on “τ-γ” dependence at the end of pseudo- yield plateau or at the beginning of the subsequent linear section of deformation development under loading. The development of plastic deformation at τ > τ_0.3 was also studied.

结果表明，在与热弹性马氏体相变，形状记忆和超弹性效应，真正的屈服应力（τ合金_0.3）可以通过“应力-总应变”和“塑性变形-总应变”依赖性的联合分析来确定。我们建议确定等温循环的“塑性变形-总变形”的相关性，即“在施加的外应力不断增加的值下加载-卸载”以及随后对未加载试样进行加热直至非弹性马氏体返回完成的等温循环。形变。在这种情况下，残余变形等于塑性变形。使用Ti _49.2 Ni _50.8（原子％）的二元合金试样，其结构从粗粒通过温轧的方式微米和submicrocrystalline，屈服点τ变为_0.3在标本扭转证实在末端上“τ-γ”依赖性进行本地化假屈服高原或在载荷作用下变形发展的后续线性部分开始时的位移。塑性变形在τ>τ发展_0.3进行了研究。