Screening of generalized stacking fault energies, surface energies and intrinsic ductile potency of refractory multicomponent alloys
Screening of generalized stacking fault energies, surface energies and intrinsic ductile potency of refractory multicomponent alloys
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DOI：
10.1016/j.actamat.2021.116800
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发表时间：
2020-08
期刊：
影响因子：
9.4
通讯作者：
Yong-Jie Hu;A. Sundar;S. Ogata;L. Qi
中科院分区：
文献类型：
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作者：
Yong-Jie Hu;A. Sundar;S. Ogata;L. Qi
体心立方（bcc）难熔多元合金由于其优异的高温强度而引起人们极大的兴趣。优化这些合金的化学成分以实现高强度和室温延展性的组合仍然具有挑战性。在广阔的成分空间中对这些相关性质进行系统预测将加快合金发现过程。本文采用准随机结构（SQS）方法，对106种二元、三元和四元体心立方固溶体合金的（1 1 <$0）[111]滑移系的不稳定层错能（γ usf）和（1 1 <$0）面表面能（γ surf）进行了第一性原理计算，合金的组成元素为Ti，Zr，Hf，V，Nb，Ta、Mo、W、Re和Ru。此外，利用第一性原理数据和一组物理信息描述符，我们开发了基于统计回归的替代模型，以准确有效地预测10元素组成空间中耐火多组分合金的γ usf和γ surf。建立在二元和三元数据上的替代模型在高阶多组分体系中表现出突出的预测能力。γ surf和γ usf之间的比率可以用于填充基于裂纹尖端变形的Rice模型的固有延性模型。因此，使用替代模型，我们对112，378种合金成分的γ usf、γ surf及其比值进行了系统筛选，以寻找可能具有增强的强度-延展性协同作用的候选合金。搜索结果也验证了额外的第一性原理计算。
Body-centered cubic (bcc) refractory multicomponent alloys are of great interest due to their remarkable strength at high temperatures. Optimizing the chemical compositions of these alloys to achieve a combination of high strength and room-temperature ductility remains challenging. Systematic predictions of these correlated properties across a vast compositional space would speed the alloy discover process. In the present work, we performed first-principles calculations with the special quasi-random structure (SQS) method to predict the unstable stacking fault energy (γ usf) of the (1 1¯ 0)[111] slip system and the (1 1¯ 0)-plane surface energy (γ surf) for 106 individual binary, ternary and quaternary bcc solid-solution alloys with constituent elements among Ti, Zr, Hf, V, Nb, Ta, Mo, W, Re and Ru. Moreover, with the first-principles data and a set of physics-informed descriptors, we developed surrogate models based on statistical regression to accurately and efficiently predict γ usf and γ surf for refractory multicomponent alloys in the 10-element compositional space. Building upon binary and ternary data, the surrogate models show outstanding predictive capability in the high-order multicomponent systems. The ratio between γ surf and γ usf can be used to populate a model of intrinsic ductility based on the Rice model of crack-tip deformation. Therefore, using the surrogate models, we performed a systematic screening of γ usf, γ surf and their ratio over 112,378 alloy compositions to search for alloy candidates that may have enhanced strength-ductility synergies. Search results were also validated by additional first-principles calculations.