First-principles study of ternary bcc alloys using special quasi-random structures
First-principles study of ternary bcc alloys using special quasi-random structures
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DOI：
10.1016/j.actamat.2009.06.026
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发表时间：
2009-09-01
期刊：
影响因子：
9.4
通讯作者：
Jiang, Chao
中科院分区：
文献类型：
--
作者：
Jiang, Chao
本文采用穷举法和MonteCarlo模拟退火相结合的方法，对三元体心立方（bcc）合金A（1）B（1）C（1），A（2）B（1）C（1），A（6）B（1）C（1）和A（2）B（3）C（3）的准随机结构进行了研究。该结构具有本地对和多位相关功能，密切模仿那些随机体心立方合金。我们用SQS方法预测了bcc结构Mo-Nb-Ta和Mo-Nb-V固溶体的混合谱、最近邻键长分布和电子态密度。我们的收敛性测试表明，即使是小规模的SQS可以给出可靠的结果。基于SQS能量学，评估了现有经验三元外推模型的预测能力。研究结果表明，为了准确描述三元合金的热力学行为，考虑三元相互作用参数是非常重要的。所提出的SQS具有较好的通用性，可应用于其它三元体心立方合金。(C)2009 Acta Materialia Inc.由爱思唯尔有限公司出版。保留所有权利。
Using a combination of exhaustive enumeration and Monte Carlo simulated annealing, we have developed special quasi-random structures (SQSs) for ternary body-centered cubic (bcc) alloys with compositions of A(1)B(1)C(1), A(2)B(1)C(1), A(6)B(1)C(1) and A(2)B(3)C(3), respectively. The structures possess local pair and multisite correlation functions that closely mimic those of the random bcc alloy. We employed the SQSs to predict the mixing enthalpies, nearest neighbor bond length distributions and electronic density of states of bcc Mo-Nb-Ta and Mo-Nb-V solid solutions. Our convergence tests indicate that even small-sized SQSs can give reliable results. Based on the SQS energetics, the predicting powers of the existing empirical ternary extrapolation models were assessed. The present results suggest that it is important to take into account the ternary interaction parameter in order to accurately describe the thermodynamic behaviors of ternary alloys. The proposed SQSs are quite general and can be applied to other ternary bcc alloys. (C) 2009 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.