摘要
用基于密度泛函理论的自洽离散变分方法研究了bcc Fe中[100](010)刃型位错扭折处掺S的电子结构,计算了杂质偏聚能、原子间相互作用能、电荷密度及态密度.计算结果表明:S引入体系后,电荷发生了重新分布,S原子得到电子,其周围Fe原子失去电子,且S原子的3p轨道与近邻Fe原子的3d4s4p轨道之间杂化,使得它们之间的成键有较强的方向性,可影响材料的韧性;而近邻Fe原子因失去电子使自身之间相互作用比未掺杂时减弱,有利于扭折的迁移,可能影响材料的强度.
Using the first-principles self-consistent discrete variational method （DVM） based on density functional theory, the effect of impurity S on the electronic structure of the kink on the [100]（010） edge dislocations （ED） in bcc iron was investigated. The segregation energy, interatomic energy, local density of states and charge density were calculated. The results show that S atom obtained electrons from its neighboring Fe atoms when a S atom was introduced into interstitial sites in the kink. It was found that there are a strong hybridization between S-3p with Fe-3d4s4p states, which led to the strong orientation bonding between them and may not benefit to toughness of material. The interactions between the Fe atoms are decreased due to Fe atoms loss electrons, which is beneficial to the migration of kink, and may decrease the strength of material.
出处
《金属学报》
SCIE
EI
CAS
CSCD
北大核心
2007年第10期1015-1019,共5页
Acta Metallurgica Sinica
基金
中南林业科技大学引进高层次人才项目启动基金资助课题06y016
关键词
BCC
FE
电子结构
刃型位错
扭折
S元素
bcc Fe, electronic structure, edge dislocation, kink, S element
