The CoCrFeMnNi high-entropy alloy (HEA) is a potential structural material, whose cyclic plasticity is essential for its safety assessment in service. Here, the effects of twin boundaries (TBs) and temperature on the cyclic plasticity of CoCrFeMnNi HEA were studied by the molecular dynamics (MD) simulation. The simulation results showed that a significant amount of lattice disorders were generated due to the interactions between partial dislocations in CoCrFeMnNi HEA during the cyclic deformation. Lattice disorder impeded the reverse movement of dislocations and then weakened Bauschinger’s effect in the HEA. The cyclic plasticity of CoCrFeMnNi HEA, especially Bauschinger’s effect, depends highly on the temperature and pre-existing TBs. Such dependence lies in the effects of temperature and pre-existing TBs on the extent of lattice disorder. This study helps further understand the cyclic plasticity of CoCrFeMnNi HEA from the atomic scale.

中文翻译：

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CoCrFeMnNi 高熵合金 (HEA) 的循环塑性：分子动力学模拟

CoCrFeMnNi高熵合金（HEA）是一种潜在的结构材料，其循环塑性对其在役安全评估至关重要。在这里，通过分子动力学 (MD) 模拟研究了孪晶界 (TB) 和温度对 CoCrFeMnNi HEA 循环塑性的影响。模拟结果表明，在循环变形过程中，由于CoCrFeMnNi HEA中部分位错之间的相互作用，产生了大量的晶格紊乱。晶格无序阻碍了位错的反向运动，然后削弱了包辛格在 HEA 中的作用。CoCrFeMnNi HEA 的循环塑性，尤其是包辛格效应，很大程度上取决于温度和预先存在的 TB。这种依赖性在于温度和先前存在的 TB 对晶格无序程度的影响。