Fe-Mn-Si-Ni-Co合金中形变诱发马氏体相变及形状记忆效应

Deformation-Induced Martensitic Transformation and Shape Memory Effect in Fe-Mn-Si-Ni-Co Alloy

通过拉伸试验、金相和透射电子显微分析,研究了Fe-25.6Mn-5.1Si-4.1Ni-1.8Co合金的形变诱发γ→ε马氏体相变与形状记忆效应。结果表明,变形温度从M_d点降至193K时,变形机制由位错滑移逐渐转变为形变诱发γ→ε马氏体相变,合金的形状记忆效应相应地近似呈线性提高。在138～193K之间变形时形状记忆效应保持稳定。文中通过分析形变诱发马氏体相变的应力-应变曲线,讨论了形状记忆效应与屈服应力之间的关系。

The deformation-induced γ→ε martensitic transformation and shape memory effect of Fe-25.6Mn-5.1Si-4.1Ni-1.8Co (wt%)alloy have bsen investigated by tensile test and optical and transmission electron microscopy. It has been found that the recovery ratio of SME decreused with increusing deformation temperature over 193～403K due to the introduction of true plastic deformation in parent phase, while it kept constant at lower temperatures over 138～193K. The correlation between the recovery ratio of SME and the yield stress of deformation-induced martensitic transformation has been discussed upon the stress-strain curves.