Predicting Atomic Arrangement of Solute Clusters in Dilute Mg Alloys
Predicting Atomic Arrangement of Solute Clusters in Dilute Mg Alloys
复制标题
DOI：
10.1080/21663831.2013.838705
复制
发表时间：
2013-01-01
影响因子：
8.3
通讯作者：
Ogata, Shigenobu
中科院分区：
文献类型：
--
作者：
Kimizuka, Hajime;Ogata, Shigenobu
多元合金非均匀原子结构的理论预测是材料科学中最具挑战性的问题之一。在这里，我们通过构建晶格上有效多体势模型来描述含有Al和Gd替代的堆垛层错（SF）的六方密堆积镁晶体的能量学，从而提出了第一性原理证明。值得注意的是，我们表明，我们的直观模型可以描述溶质原子的SFs的偏析，并再现特征的短程化学顺序在稀Mg-Gd和Mg-Al-Gd系统，包括长周期堆叠有序结构，在最近的扫描透射电子显微镜测量的方式一致。
Theoretical prediction of the heterogeneous atomic structures in multicomponent alloys is one of the most challenging issues in materials science. Here we present a first-principles demonstration of this by constructing an on-lattice effective multibody potential model to describe the energetics of hexagonal close-packed Mg crystals containing stacking faults (SFs) with Al and Gd substitutions. Remarkably, we showed that our intuitive model can describe the segregation of solute atoms to SFs and reproduce the characteristic short-range chemical order in dilute Mg-Gd and Mg-Al-Gd systems, including long-period stacking ordered structures, in a manner consistent with recent scanning transmission electron microscopy measurements.