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研究发现低层错能的亚稳材料低温拉伸存在一种新型的应力应变曲线．曲线表现为弹塑性失稳εｐｈ 、应力平台εＬ 及硬化指数ｎ 为不恒值的３ 个特点．试验结果表明：εｐｈ 、εＬ 随应变率增加而增大，硬化率ｄσ／ｄε与硬化指数ｎ 随应变量的增加呈抛物线型．弹塑性失稳及应力平台本质上不同于稳定态材料的上、下屈服及屈服平台，而是由相变引起的新的屈服机制，即弹塑性失稳是应变诱发马氏体转变的起始状态，应力平台是相变软件与硬化动态平衡的结果
It is found that there is a new type of stress-strain curve in low-temperature drawing of metastable materials with lower fault energy. The curves show three characteristics of elastic-plastic instability εph, stress platform εL and hardening index n as non-constant values. The experimental results show that εph and εL increase with the increase of strain rate, and the hardening rate dσ / dε and hardening exponent n become parabolic with the increase of strain. Elasto-plastic instability and stress platforms are fundamentally different from the upper and lower yielding and yielding platforms of the steady-state materials, but rather a new yield mechanism due to phase transitions, ie elastoplastic instability is the beginning of strain-induced martensitic transformation State, stress platform is the result of phase change software and hardening dynamic balance