Experiments were conducted to examine the effects of prior cold rolling and subsequent heat treatment on the microstructure, phase evolution and mechanical properties of an Fe–10Ni–7Mn martensitic steel. The results show that 70% cold rolling leads to deformation-induced austenite formation in the microstructure and reduces the size of the martensite blocks. Prior cold rolling increases the reversed austenite volume fraction under post-deformation intercritical annealing (PDIA) at 600 °C compared with the solution annealed condition. Electron back scattering diffraction and dilatometric studies showed that under PDIA there is a reverse transformation of martensite to austenite through a sequential combination of martensitic and diffusional mechanisms. There is also a precipitation of θ-NiMn particles in the PDIA specimen after subsequent ageing leading to an increase in the ultimate tensile strength in tensile testing. Cyclic tensile testing revealed pseudoelastic behavior in the cold-rolled specimen but this disappeared after PDIA and appeared again after subsequent ageing.

进行实验以检验先前的冷轧和后续的热处理对Fe-10Ni-7Mn马氏体钢的组织，相演变和力学性能的影响。结果表明，70％的冷轧导致组织中形变引起的奥氏体形成，并减小了马氏体块的尺寸。与固溶退火条件相比，在600°C的变形后临界退火（PDIA）下，先前的冷轧会增加反向奥氏体的体积分数。电子背散射衍射和膨胀学研究表明，在PDIA下，通过马氏体和扩散机制的顺序结合，马氏体向奥氏体反向转变。在随后的时效处理后，PDIA样品中还会析出θ-NiMn颗粒，从而导致抗拉试验的极限抗拉强度增加。循环拉伸试验显示了冷轧试样的伪弹性行为，但在PDIA后消失，在随后的时效后再次出现。