We studied the development and element partitioning for σ-phase precipitation during hot compression of the CoCrFeMnNi HEA. The σ-phase mainly observed in the necklaced area (NA), where dynamic recrystallization (DRX) occurred but did not occur in the deformed area (DA). The σ-phase increases the hardness and elastic modulus measured by nanoindentation in NA, compared to that of DA. Several defects are transferred by the interface reaction of the crystal grains accompanied by the partitioning of the Cr and Ni elements. This results in the accelerated dynamic precipitation of the Cr-rich σ-phase.

中文翻译：

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等原子CoCrFeMnNi高熵合金中σ相的动态析出和元素分配

我们研究了CoCrFeMnNi HEA热压缩过程中σ相沉淀的发展和元素分配。σ相主要在颈缩区域（NA）处观察到，该区域发生了动态重结晶（DRX），而在变形区域（DA）中没有发生。与DA相比，σ相增加了NA中通过纳米压痕测得的硬度和弹性模量。晶粒的界面反应伴随着Cr和Ni元素的分配转移了一些缺陷。这导致富铬σ相的动态沉淀加速。