This paper advances crystallographically-based Olson-Cohen (direct γ → α’) and deformation mechanism (indirect γ→ε→α’) phase transformation models for predicting strain-induced austenite to martensite transformation. The advanced transformation models enable predictions of not only strain-path sensitive, but also of strain-rate and temperature sensitive deformation of polycrystalline stainless steels (SSs). The deformation of constituent grains in SSs is modeled as a combination of anisotropic elasticity, crystallographic slip, and phase transformation, while the hardening is based on the evolution of dislocation density and explicit shifts in phase fractions. Such grain-scale deformation is implemented within the meso‑scale elasto-plastic self-consistent (EPSC) homogenization model, which is coupled with the implicit finite element (FE) method to provide a constitutive response at each FE integration point for solving boundary value problems at the macro-scale. Parameters pertaining to the hardening and transformation models within FE-EPSC are calibrated and validated on a suite of data including flow curves and phase fractions for monotonic compression, tension, and torsion as a function of strain-rate and temperature for wrought and additively manufactured (AM) SS304L. To illustrate the potential and accuracy of the integrated multi-level FE-EPSC simulation framework, geometry, mechanical response, phase fractions, and texture evolution are simulated during gas-gun impact deformation of a cylinder and quasi-static tension of a notched specimen made of AM SS304L. Details of the simulation framework, comparison between experimental and simulation results, and insights from the results are presented and discussed.

本文提出了基于晶体学的 Olson-Cohen（直接γ → α'）和变形机制（间接γ→ε→α') 相变模型，用于预测应变诱发的奥氏体到马氏体的转变。先进的转变模型不仅可以预测应变路径敏感，还可以预测多晶不锈钢 (SS) 的应变速率和温度敏感变形。SSs 中组成晶粒的变形被建模为各向异性弹性、晶体滑移和相变的组合，而硬化是基于位错密度的演变和相分数的显式变化。这种晶粒尺度变形是在中尺度弹塑性自洽 (EPSC) 均匀化模型中实现的，该模型与隐式有限元 (FE) 方法相结合，在每个 FE 积分点提供本构响应以求解边界值宏观层面的问题。与 FE-EPSC 中的硬化和转变模型相关的参数在一系列数据上进行校准和验证，包括单调压缩、拉伸和扭转的流动曲线和相分数，作为锻造和增材制造的应变率和温度的函数。上午）SS304L。为了说明集成的多级 FE-EPSC 模拟框架的潜力和准确性，在气缸的气枪冲击变形和制成的缺口试样的准静态张力期间模拟几何、机械响应、相分数和纹理演变AM SS304L。介绍和讨论了模拟框架的细节、实验和模拟结果之间的比较以及结果的见解。