Abstract This present work simulated the coherent BCC/B2 microstructures existing in body-centered-cubic (BCC)-based Al-Ni-Co-Fe-Cr high entropy alloys (HEAs) in light of the phase-field method. These coherent BCC/B2 microstructures contain spherical or cuboidal nanoprecipitates, or exhibit a weave-like spinodal decomposition in experiments. Based on the Chan-Hilliard equation, a two-dimensional phase field model was established using the COMSOL Multiphysics software to reveal the coherent microstructural evolutions of the present HEAs. It was found that the simulations of spherical/cuboidal nanoprecipitations and weave-like spinodal decomposition are well consistent with the experimental results. Both the lattice misfit and the anisotropy difference of Young's moduli between the precipitated phase and matrix phase affect the precipitate morphology, in which the cuboidal nanoprecipitation is especially susceptible to the modulus anisotropy. The coarsening behavior of precipitates is also discussed with the aid of the simulation results. The phase-field simulation will provide an important technique to predict the microstructural evolution and to assist the composition design of new HEAs.

中文翻译：

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高熵合金相干 BCC/B2 微观结构的相场模拟

摘要 本工作根据相场法模拟了体心立方 (BCC) 基 Al-Ni-Co-Fe-Cr 高熵合金 (HEAs) 中存在的相干 BCC/B2 微观结构。这些连贯的 BCC/B2 微结构包含球形或立方体纳米沉淀物，或在实验中表现出类似编织的旋节线分解。基于 Chan-Hilliard 方程，使用 COMSOL Multiphysics 软件建立了二维相场模型，以揭示当前 HEAs 的相干微观结构演变。发现球形/立方体纳米沉淀和编织状旋节线分解的模拟与实验结果非常一致。Young' 的晶格失配和各向异性差异 沉淀相和基体相之间的 s 模量影响沉淀形态，其中立方纳米沉淀特别容易受到模量各向异性的影响。还借助模拟结果讨论了析出物的粗化行为。相场模拟将提供一种重要的技术来预测微观结构演变并协助新 HEA 的成分设计。