Multi-principal-element alloys (MPEAs) based on -transition metals show remarkable mechanical properties. The stacking fault energy (SFE) in face-centered cubic (fcc) alloys is a critical property that controls underlying deformation mechanisms and mechanical response. Here, we present an exhaustive density-functional theory study on refractory- and copper-reinforced Cantor-based systems to ascertain the effects of refractory metal chemistry on SFE. We find that even a small percent change in refractory metal composition significantly changes SFEs, which correlates favorably with features like electronegativity variance, size effect, and heat of fusion. For fcc MPEAs, we also detail the changes in mechanical properties, such as bulk, Young's, and shear moduli, as well as yield strength. A Labusch-type solute-solution-strengthening model was used to evaluate the temperature-dependent yield strength, which, combined with SFE, provides a design guide for high-performance alloys. We also analyzed the electronic structures of two down-selected alloys to reveal the underlying origin of optimal SFE and strength range in refractory-reinforced fcc MPEAs. These new insights on tuning SFEs and modifying composition-structure-property correlation in refractory- and copper-reinforced MPEAs by chemical disorder, provide a chemical route to tune twinning- and transformation-induced plasticity behavior.

中文翻译：

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了解难熔金属化学对康托基多主元合金堆垛层错能和力学性能的影响


基于过渡金属的多主元素合金（MPEA）表现出卓越的机械性能。面心立方 (fcc) 合金中的堆垛层错能 (SFE) 是控制潜在变形机制和机械响应的关键属性。在这里，我们对基于难熔和铜增强的康托系统进行了详尽的密度泛函理论研究，以确定难熔金属化学对 SFE 的影响。我们发现，即使难熔金属成分发生很小的百分比变化，SFE 也会发生显着变化，这与电负性方差、尺寸效应和熔化热等特征密切相关。对于面心立方 MPEA，我们还详细介绍了机械性能的变化，例如体积模量、杨氏模量和剪切模量以及屈服强度。 Labusch型溶质-溶液强化模型用于评估温度相关的屈服强度，该模型与SFE相结合，为高性能合金提供了设计指南。我们还分析了两种向下选择的合金的电子结构，以揭示耐火增强面心立方 MPEA 中最佳 SFE 和强度范围的根本原因。这些关于通过化学无序调节 SFE 和修改耐火增强和铜增强 MPEA 中的成分-结构-性能相关性的新见解，为调节孪晶和相变诱导的塑性行为提供了一条化学途径。