Ferrous medium-entropy alloys (FeMEAs), leveraging deformation-induced martensitic transformation (DIMT), demonstrate excellent strain-hardening ability attributed to the transformation-induced plasticity (TRIP) effect. To improve the low yield strength of FeMEAs, the initial microstructure was controlled by utilizing partial recrystallization. The intricate initial microstructure, a blend of recrystallized (ReX) and non-recrystallized (non-ReX) regions, results in complex deformation behavior where DIMT in both the ReX and non-ReX regions are simultaneously activated, posing significant analytical challenges. In this paper, we perform in-situ synchrotron X-ray diffraction during the tensile loading on a partially recrystallized metastable Fe57.5Co18Cr13Ni7.5Mo3C1 (at%) FeMEA to quantitatively analyze each deformation mechanism. The innovative idea of peak deconvolution enables separate tracing of the deformation behavior of the ReX and non-ReX FCC domains, revealing the stress partitioning between them. DIMT kinetics in each domain are investigated by the evolution of domain fractions, and we provide a detailed discussion on how both of them exhibit rapid DIMT kinetics. Furthermore, we measure the contributions of DIMT occurring in each domain on the global strain-hardening rate. The results suggest that the predominant contribution shifts from DIMT in the ReX domain to DIMT in the non-ReX domain as deformation progresses, highlighting the distinctive strain-hardening mechanisms between the ReX and non-ReX domains. This work demonstrates how a partially recrystallized metastable FeMEA exhibits superior mechanical properties and provides insights into analyzing the complex deformation behavior.

中文翻译：

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部分再结晶的亚稳态中等熵合金的复杂变形行为：原位同步辐射 X 射线衍射研究


铁介质熵合金 （FeMEA） 利用变形诱导马氏体转变 （DIMT），由于转变诱导塑性 （TRIP） 效应而表现出优异的应变硬化能力。为了提高 FeMEAs 的低屈服强度，通过利用部分再结晶来控制初始微观结构。错综复杂的初始微观结构，即再结晶 （ReX） 和非再结晶 （non-ReX） 区域的混合物，导致复杂的变形行为，其中 ReX 和非 ReX 区域的 DIMT 同时被激活，带来了重大的分析挑战。在本文中，我们在部分再结晶的亚稳态 Fe57.5Co18Cr13Ni7.5Mo3C1 （at%） FeMEA 上进行原位同步加速器 X 射线衍射，以定量分析每种变形机制。峰值反卷积的创新理念能够单独追踪 ReX 和非 ReX FCC 域的变形行为，从而揭示它们之间的应力分配。通过结构域分数的演变来研究每个结构域中的 DIMT 动力学，我们详细讨论了它们如何表现出快速的 DIMT 动力学。此外，我们测量了每个域中发生的 DIMT 对整体应变硬化率的贡献。结果表明，随着变形的进行，主要贡献从 ReX 域中的 DIMT 转移到非 ReX 域中的 DIMT，突出了 ReX 和非 ReX 域之间独特的应变硬化机制。这项工作展示了部分重结晶的亚稳态 FeMEA 如何表现出卓越的机械性能，并为分析复杂的变形行为提供了见解。