Fe-X (X = Si, Cr, Mn, Ni)二元合金结构和弹性性质的第一性原理计算

First-Principles Study on Structure and Elastic Properties of Fe-X (X = Si, Cr, Mn, Ni) Binary Alloy

摘要: 采用基于密度泛函理论的第一性原理计算方法，系统研究了Si, Cr, Mn, Ni等合金元素对面心立方结构Fe的晶体结构和弹性性质的影响规律。结果表明，不同合金化元素(Si, Cr, Mn, Ni)的加入都使面心立方Fe晶胞的晶格常数增大，晶胞体积增加。加入合金元素后，二元合金体系都满足力学稳定性条件；弹性常数C₁₁, C₁₂和C₄₄几乎都增加，弹性模量都出现增大，泊松比整体变化不大。

Abstract: The effects of alloying element such as Si, Cr, Mn and Ni on the structure and elastic properties of face centered cubic Fe were investigated by the method of the first-principles based on density functional theory. The results showed that the alloying elements (Si, Cr, Mn, Ni) were all increased the lattice constant of face centered cubic Fe, and thus increased the cell volume. After adding the alloying elements, the all binary alloy systems meet the mechanical stability conditions. The elastic constants of C₁₁, C₁₂, and C₄₄ were increased almost all, the elastic moduli were increased also and the Poisson’s ratio was changed little as a whole.