First-principle investigation of bismuth segregation atΣ5 (012) grain-boundaries in nickel

被引：0

作者：

陈律 ^{[1
,2
]}

彭平 ^{[3
]}

庄厚龙 ^{[3
]}

周惦武 ^{[4
]}

机构：

[1] Department of Aeronautical Equip EngineeringChangsha Aeronautical Vocational and Technical College,Changsha ,China

[2] School of Materials Science and Engineering,Hunan University,Changsha ,China

[3] School of Materials Science and EngineeringHunan University,Changsha ,China

[4] School of Materials Science and Engineering Hunan University, Changsha ,China

来源：

Transactions of Nonferrous Metals Society of China | 2006年 / S2期

关键词：

nickel; grain boundary; surface energy; Griffith work; segregation;

D O I：

暂无

中图分类号：

TG111.1 [金属的电子理论];

学科分类号：

0702 ; 070205 ;

摘要：

<正>As an aid in establishing an understanding on the electronic level, the influence of bismuth on the cohesion of nickelΣ5 (012) grain boundary was determined using the plane wave pseudopotential (PWPP) method with the generalized gradient approximation. Based on the Rice-Wang model, the total energy calculations show that Bi behaves as an embrittler of the Ni grain-boundary, which predicts the experimentally known behavior. The total charge density, and difference charge density of the grain boundary also demonstrats that the Bi atom forms weaker bonds with neighboring Ni atoms in the grain boundary region. Total density of states (DOS) show that there exists significant covalent bonding for the grain boundary system with Bi segregated which help to embrittle the grain boundary and the change that Ni local d-DOS is narrowed due to segregation of Bi is also beneficial for the decohesion.

引用

页码：813 / 819

页数：7