Al,Cr共偏析α-Fe晶界对其结合强度影响的第一性原理研究  

First-principles study on the effects of co-segregation of Al,Cr on the cohesion of the α-Fe grain boundary

作　　者：李春霞[1,2] 党随虎[1,2] 韩培德[1] 

机构地区：[1]太原理工大学材料科学与工程学院,太原030024 [2]长江师范学院物理与电子工程学院,重庆408003

出　　处：《原子与分子物理学报》2014年第3期470-474,共5页Journal of Atomic and Molecular Physics

基　　金：重庆市科委科学技术研究项目(2012jjA90017;KJ131315;KJ131308);长江师范学院校级研究项目(2012XJYB062)

摘　　要：在密度泛函理论的框架下,采用广义梯度近似(GGA)研究了合金化元素Al,Cr在α-Fe+(210)晶界共偏析的作用.结果表明Cr提高了Fe晶界结合,为韧性杂质;而Al减弱了晶界的结合,是脆性杂质.Cr不能够彻底地消除Al的脆化作用,反而使其脆性增强.基于偏聚能分析表明Cr能有效地抑制Al偏析到晶界,提高α-Fe的力学性能.The effects of Al, Cr co-segregating on the α-Fe ∑（210） grain boundary are studied by a first- principles method, CASTEP. We found that Cr acts as an enhancer, while for Al element, its segregation increases the grain boundary embrittlement. Cr can not completely eliminate the embrittlement for Al element, oppositely making its brittleness increased. Based on the segregation energy analysis, it is also found that Cr can effectively prohibit Al from segregating to the grain boundary and therefore change the mechanical properties in α-Fe.

关 键 词：α-Fe晶界 合金化元素 偏析 第一性原理研究 

分 类 号：O561[理学—原子与分子物理]