Cr、Mo对DO_3-Fe_3Al力学性能和电子结构影响的第一性原理计算  

Theoretical Research on Effect of Cr,Mo on Mechanical Properties and Electronic Structure of DO_3-Fe_3Al

作　　者：陈煜[1,2] 姚正军[2] 张平则[2] 罗西希[2] 韩培德[3] 

机构地区：[1]南京工业职业技术学院,江苏南京210046 [2]南京航空航天大学,江苏南京211100 [3]太原理工大学,山西太原030024

出　　处：《稀有金属材料与工程》2017年第10期2863-2869,共7页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(51371097);江苏省"六大人才高峰"第十二批高层次人才项目(YPC16005-PT);江苏省"青蓝工程"项目;江苏省"高级访问工程师"项目

摘　　要：采用基于密度泛函理论的第一性原理方法,研究了Cr、Mo在DO_3-Fe_3Al金属间化合物中的占位以及对Fe_3Al力学性能和电子结构的影响。研究显示:Cr、Mo在Fe_3Al中优先替代Al原子;Cr、Mo的添加均提升了Fe_3Al的体模量、剪切模量、弹性模量以及塑性,其中Mo对Fe_3Al的模量以及塑性的提升效果更明显;Cr和Mo同时添加提高了Fe_3Al的体模量、剪切模量、弹性模量,然而略微降低了其塑性。电子结构和电荷密度分析表明:Cr、Mo对Fe_3Al力学性能提高的主要原因是Cr、Mo的s,p和d轨道电子参与了Fe_3Al的电子杂化,Cr、Mo增加了Fe_3Al的成键峰数量,且增加了Fe_3Al中原子间的重叠电子数。此外,Cr、Mo减弱了Fe_3Al中Fe-Fe间电子云的方向性。The preferred site of Cr or Mo alloying element in the DO_3-Fe_3 Al intermetallic compounds, and the effect of Cr or Mo on the mechanical properties and electronic structure of Fe_3 Al were investigated by first-principle based on density functional theory. The research demonstrates that Cr or Mo substitutes the Al atom preferably in Fe_3 Al, and Cr or Mo increases the bulk moduli, rigidity moduli and Young＇s modulus of Fe_3 Al and improves the ductility of Fe_3 Al, and Cr and Mo together improves the bulk moduli, rigidity moduli and Young＇s modulus of Fe_3 Al, but decreases slightly the ductility of Fe_3 Al. According to the analysis of the electronic structure and the electronic density, the improvement of the mechanical properties of Fe_3 Al can be mainly attributed to that the s, p, d-state orbital electron of the element Cr or Mo is involved in hybridization of Fe_3 Al, Cr or Mo increases the number of the bonding peaks of Fe_3 Al and overlapping electron number among atoms of Fe_3 Al. In addition, Cr or Mo decreases the directionality of electron atmosphere between Fe-Fe of Fe_3 Al.

关 键 词：DO3-Fe3Al金属间化合物 合金化效应 第一性原理 力学性能 电子结构 

分 类 号：O469[理学—凝聚态物理]