The generalized stacking fault energy (GSFE) is a material property that can provide invaluable insights into describing nanoscale plasticity phenomena in crystalline materials. Lattice strains have been suggested to influence such phenomena. Here, the GSFE curves for sequential faulting pathways in dual phase [face-centered cubic (fcc) and hexagonal close-packed (hcp)] ${\mathrm{Cr}}_{20}{\mathrm{Mn}}_{20}{\mathrm{Fe}}_{20}{\mathrm{Co}}_{20}{\mathrm{Ni}}_{20}, {\mathrm{Cr}}_{25}{\mathrm{Fe}}_{25}{\mathrm{Co}}_{25}{\mathrm{Ni}}_{25}, {\mathrm{Cr}}_{20}{\mathrm{Mn}}_{20}{\mathrm{Fe}}_{34}{\mathrm{Co}}_{20}{\mathrm{Ni}}_6, {\mathrm{Cr}}_{20}{\mathrm{Mn}}_{20}{\mathrm{Fe}}_{30}{\mathrm{Co}}_{20}{\mathrm{Ni}}_{10}$, and ${\mathrm{Cr}}_{10}{\mathrm{Mn}}_{30}{\mathrm{Fe}}_{50}{\mathrm{Co}}_{10}$ high-entropy alloys are investigated on ${\left\{111\right\}}_{\text{fcc}}$ and ${\left(0002\right)}_{\text{hcp}}$ close-packed planes using density-functional calculations. The dependence of GSFEs on imposed volumetric and longitudinal lattice strains is studied in detail for ${\mathrm{Cr}}_{20}{\mathrm{Mn}}_{20}{\mathrm{Fe}}_{20}{\mathrm{Co}}_{20}{\mathrm{Ni}}_{20}$ and ${\mathrm{Cr}}_{10}{\mathrm{Mn}}_{30}{\mathrm{Fe}}_{50}{\mathrm{Co}}_{10}$. The competition between various plastic deformation modes is discussed for both phases based on effective energy barriers determined from the calculated GSFEs and compared with experimentally observed deformation mechanisms. The intrinsic stacking fault energy, unstable stacking fault energy, and unstable twinning fault energy are found to be closely related in how they are affected by applied strain. The ratio of two of these planar fault energies can thus serve as characteristic material property. An inverse relationship between the intrinsic stacking fault energy in the hcp phase and the axial ratio ${(c/a)}_{\text{hcp}}$ is revealed and explained via band theory.

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应变对 fcc-hcp 多晶型高熵合金广义堆垛层错能和塑性变形模式的影响：第一性原理研究

广义堆垛层错能 (GSFE) 是一种材料特性，可以为描述晶体材料中的纳米级塑性现象提供宝贵的见解。已经建议晶格应变影响这种现象。此处，双相 [面心立方 (fcc) 和六方密堆积 (hcp)] 中连续断层路径的 GSFE 曲线${铬}_{20}{锰}_{20}{铁}_{20}{\mathrm{公司}}_{20}{你}_{20}, {铬}_{25}{铁}_{25}{\mathrm{公司}}_{25}{你}_{25}, {铬}_{20}{锰}_{20}{铁}_{34}{\mathrm{公司}}_{20}{你}_6, {铬}_{20}{锰}_{20}{铁}_{30}{\mathrm{公司}}_{20}{你}_{10}$， 和 ${铬}_{10}{锰}_{30}{铁}_{50}{\mathrm{公司}}_{10}$ 高熵合金的研究 ${\left\{111\right\}}_{\text{联邦通信委员会}}$ 和 ${\left(0002\right)}_{\text{医管局}}$使用密度泛函计算的密堆积平面。详细研究了 GSFE 对施加的体积和纵向晶格应变的依赖性${铬}_{20}{锰}_{20}{铁}_{20}{\mathrm{公司}}_{20}{你}_{20}$ 和 ${铬}_{10}{锰}_{30}{铁}_{50}{\mathrm{公司}}_{10}$. 基于从计算的 GSFE 确定的有效能垒并与实验观察到的变形机制进行比较，讨论了两个阶段的各种塑性变形模式之间的竞争。发现固有层错能、不稳定层错能和不稳定孪晶错能与它们如何受外加应变的影响密切相关。因此，这些平面故障能量中的两个的比率可以用作特征材料特性。hcp 相中的固有堆垛层错能与轴比之间的反比关系${(C/\mathrm{一种})}_{\text{医管局}}$ 通过能带理论揭示和解释。