论文标题
将电子结构计算与多组分合金中的通用堆叠故障链接起来
Linking electronic structure calculations to generalized stacking fault energies in multicomponent alloys
论文作者
论文摘要
广义堆叠断层能是中位错模型的关键要素。在这里，我们开发了一种量化广义堆叠断层能对多组分合金化学疾病程度的依赖性的方法。我们介绍了“构型分辨平面断层”（CRPF）能量的概念，并将群集扩展方法从合金理论扩展，以表达CRPF作为围绕故障位点的化学占用变量的函数。我们采用该方法来探索二进制MO-NB合金中不稳定堆叠断层能（USF）的组成和温度依赖性。第一原理计算用于参数化地层能量和CRPF群集扩展。蒙特卡洛模拟表明，USF能量的分布受到化学成分和温度的显着影响。形式主义可以应用于任何多组分合金，并将能够开发严格的模型，以用于高渗透合金中的变形机制。
The generalized stacking fault energy is a key ingredient to mesoscale models of dislocations. Here we develop an approach to quantify the dependence of generalized stacking fault energies on the degree of chemical disorder in multicomponent alloys. We introduce the notion of a "configurationally-resolved planar fault" (CRPF) energy and extend the cluster expansion method from alloy theory to express the CRPF as a function of chemical occupation variables of sites surrounding the fault. We apply the approach to explore the composition and temperature dependence of the unstable stacking fault energy (USF) in binary Mo-Nb alloys. First-principles calculations are used to parameterize a formation energy and CRPF cluster expansion. Monte Carlo simulations show that the distribution of USF energies is significantly affected by chemical composition and temperature. The formalism can be applied to any multicomponent alloy and will enable the development of rigorous models for deformation mechanisms in high-entropy alloys.
