纳米孔洞对Ni/Ni_(3)Al纳米线形变行为影响的原子模拟  

Effect of Nanovoid on Deformation Behavior of Ni/Ni_(3)Al Nanowires:Atomisitic Simulation

作　　者：阳喜元 YANG Xiyuan(School of Physical Science and Technology,Lingnan Normal University,Zhanjiang,Guangdong 524048,China)

机构地区：[1]岭南师范学院物理科学与技术学院

出　　处：《计算物理》2022年第6期727-732,共6页Chinese Journal of Computational Physics

基　　金：广东省自然科学科学基金(2017A030307015);岭南师范学院科研项目(YB2116)资助

摘　　要：结合改进型嵌入原子势函数,利用分子动力学模拟Ni/Ni_(3)Al纳米线在单轴拉伸应变条件下的形变过程,研究其内在机制。结果表明:Ni/Ni_(3)Al纳米线的形变过程分为弹性、塑性形变两个阶段。在弹性形变阶段,其应力随着形变量变化呈线性关系,通过拟合发现其弹性模量约等于120 GPa,明显低于相应的块体材料结果。在此基础上,重点分析纳米孔洞对Ni/Ni_(3)Al纳米线形变行为的影响,发现纳米孔洞的存在有效地破坏合金材料内部的微观结构,使得晶格位错交割无法形成,导致晶格滑移比较容易产生,从而降低合金纳米线的弹性模量等。Deformation process of Ni/Ni_(3)Al nanowires under uniaxial tension was studied with molecular dynamics simulation.It showed that the deformation behavior of Ni/Ni_(3)Al nanowire is composed of elastic deformation and plastic deformation.The stress increased linearly with incremental strain in elastic deformation.The elastic modulus fitted from stress⁃strain relation is about 120 GPa,which os lower than those of bulk materials.It indicated that nanovoid has great impact on mechanical properties of Ni/Ni_(3)Al nanowires.It restrains effectively the crystalline glide.

关 键 词：形变行为 纳米孔洞 Ni/Ni_(3)Al纳米线 原子模拟 

分 类 号：O483[理学—固体物理] TB31[理学—物理]