摘要
晶界对于金属和合金材料的力学性能至关重要。晶界本身相对于晶内结合性能差,是导致合金延展性低的一个重要原因。因此,有必要改善其晶界结合性能,进而提高材料的延展性。利用物理冶金及合金化方法可以改善有序金属间化合物的延展性和可加工性。添加合金化元素可以有效地控制晶界的结构,达到提高晶界结合性能的目的。利用第一性原理方法在原子尺度上研究了P掺杂在Ni_(3)AlΣ5(210)晶界中的偏聚行为及晶界结合性能的增强机制。计算的偏聚能表明,相对于体位置,P原子倾向于向晶界偏聚,且向纯Ni的晶界孔隙中由8个Ni原子围成的间隙位置偏聚的趋势最大。计算晶界断裂过程中的格里菲斯功显示P的晶界偏聚可以改善晶界的结合性能。
Grain boundaries are vital to the mechanical properties of metals and alloys.The poor binding properties of grain boundaries are responsible for the low ductility of alloys.Therefore,it is necessary to enhance the binding properties of grain boundaries,so as to improve the ductility of materials.The ductility and machinability of ordered intermetallic compounds can be improved by physical metallurgy and alloying.Alloying elements can be effectively used to control the structures and improve the binding properties of grain boundaries.In this work,the first-principles method is used to investigate the segregation behavior and enhancement mechanism of the additive P in the Ni_(3)AlΣ5(210)grain boundary at the atomic scale.The calculated segregation energy shows that the P atoms tend to segregate towards the grain boundary with respect to the bulk position,especially staying at the interstitial sites surrounded by eight Ni atoms in the Ni grain boundary holes.The calculated Griffith work shows that P doping can enhance the binding property of grain boundaries.
作者
黄仁忠
刘雅娟
刘丽丽
高天附
封文江
HUANG Renzhong;LIU Yajuan;LIU Lili;GAO Tianfu;FENG Wenjiang(College of Physical Science and Technology,Shenyang Normal University,Shenyang 110034,China)
出处
《沈阳师范大学学报（自然科学版）》
CAS
2023年第5期396-401,共6页
Journal of Shenyang Normal University:Natural Science Edition
基金
辽宁省教育厅基本科研项目(LJKMZ20221466)。
关键词
金属间化合物
晶界
第一性原理
偏聚能
intermetallic compounds
gain boundary
first-principles
segregation energy
