In this paper, a new constitutive model for plastic behavior of the metastable austenitic stainless steels at cryogenic temperatures is presented. The constitutive model is a phenomenological hyperelastic-based large deformation model developed in the framework of continuum damage mechanics considering the dissipative phenomena of strain-induced phase transformation and damage growth during plastic deformation. To solve the coupled nonlinear set of equations, incremental equations and the related implicit integration method have been developed. Numerical analysis is performed by implementing the constitutive model in a UMAT subroutine in ABAQUS/STANDARD. In addition, experiments have been conducted to identify the material model parameters for AISI304 steel at the 77K temperature. In addition to calibration, the constitutive model was validated via a tensile test of a notched sample. Also, the model has been compared with the experimental data at 4.2 K available in the literature. The results show that the model is well able to predict the hardening behavior, martensite evolution, and damage growth during the plastic deformation until the fracture with acceptable accuracy.

在本文中，提出了一种新的亚稳态奥氏体不锈钢在低温下塑性行为的本构模型。本构模型是考虑塑性变形过程中应变诱导相变和损伤增长的耗散现象，在连续损伤力学框架下开发的基于唯象超弹性的大变形模型。为了求解耦合的非线性方程组，已经开发了增量方程和相关的隐式积分方法。通过在 ABAQUS/STANDARD 的 UMAT 子程序中实现本构模型来进行数值分析。此外，还进行了实验以确定 AISI304 钢在 77K 温度下的材料模型参数。除了校准，通过缺口样品的拉伸试验验证了本构模型。此外，该模型已与文献中可用的 4.2 K 实验数据进行了比较。结果表明，该模型能够很好地预测塑性变形过程中的硬化行为、马氏体演化和损伤扩展，直至断裂，并具有可接受的精度。