含表界面效应的核壳纳米线界面失配位错形核  

Misfit dislocations in an annular strained film grown on core-shell nanowires surface with surface/interface effects

作　　者：章的[1,2] 刘又文[1,2] 赵迎新[1,2] 

机构地区：[1]湖南大学汽车车身先进设计制造国家重点实验室,长沙410082 [2]湖南大学机械与运载工程学院,长沙410082

出　　处：《应用力学学报》2013年第6期859-863,952,共5页Chinese Journal of Applied Mechanics

基　　金：国家自然科学基金(11172094;11172095);重点实验室自主课题项目(51075001)

摘　　要：研究了考虑表面和界面效应的核壳纳米线材料中螺型失配位错形核的临界情况。运用复势方法获得了纳米线和薄膜区域复势函数的解析解。主要讨论了表面和界面效应对核壳纳米线中螺型失配位错形核的影响规律。研究表明:正(负)表面、界面效应会减小(增大)螺型失配位错形核时所需的膜厚度范围和临界剪切模量;当其他参量为某些定值时,无论膜厚度为多大,正表面、界面弹性常数都存在使螺型位错不能形核的可能;正(负)表面、界面残余应力会增大(缩小)螺型失配位错形核时所需的膜厚度范围;正(负)表面、界面效应会增大(减小)螺型失配位错形核时所需的临界膜厚度和失配应变临界值。The critical formation condition of screw misfit dislocation which locates in core-shell nanowires surface with interface stress is investigated. The analytical solutions of complex potential functions in the film and the nanowires are derived by means of the complex variable method. Influence of the surface/interface effects on the formation of misfit dislocation which grows on core-shell nanowires surface is discussed. Results obtained show that positive(negative) surface/interface effects decrease(increase) the critical film thickness and critical shear modulus. When the composite substrate and film of the relative shear modulus exceeds a certain value, screw misfit dislocation can not be formed when considering positive surface/interface effects. The positive(negative) surface/interface residual stress will increase(decrease) the extent of critical film thickness. The positive(negative) surface/interface effects will increase(decrease) the critical film thickness and the critical misfit strain.

关 键 词：螺型失配位错 核壳纳米线 临界膜厚度 表界面效应 

分 类 号：O346[理学—固体力学]