摘要
利用复变函数方法研究了刃型位错在含界面效应纳米尺寸夹杂中的稳定性问题。求解了作用在位错上的像力的精确表达式,给出了位错在纳米夹杂中稳定存在的夹杂临界半径条件。并且讨论了夹杂尺寸和界面效应等因素对夹杂临界半径的影响。研究表明:如果夹杂的半径保持不变,存在一个临界相对剪切模量或临界基体材料泊松比改变位错在夹杂中的稳定性。同时,临界夹杂半径随着基体材料的软化而增加。另外,界面应力不仅能改变位错在纳米夹杂中的稳定特性,而且能改变夹杂临界半径的大小。
The stability of edge dislocations in a nanoscale cylindrical inhomogeneity with interface stresses is investigated by means of a complex variable method.The explicit expression for the image force acting on the edge dislocation is obtained.The critical radius of the inhomogeneity of the dislocation stability in the nanoscale inhomogeneity is derived.The influence of the interface stresses on the critical radius of the inhomogeneity is evaluated.If the material constants and the radius of the inhomogeneity are fixed,a critical value of the shear modulus or the Poisson＇s ratio of the matrix may exist,which can change the edge dislocation stability in the inhomogeneity.The critical radius of the inclusion increases with the decrease of the shear modulus or the Poisson＇s ratio of the matrix.In addition,the interface stresses can not only change the property of the edge dislocation stability in the nanoscale inhomogeneity,but also change the value of the critical radius of the inhomogeneity under certain conditions.
出处
《工程力学》
EI
CSCD
北大核心
2011年第1期31-36,共6页
Engineering Mechanics
基金
国家自然科学基金项目(50801025
10872065
10902034)
关键词
刃型位错
夹杂
界面应力
像力
稳定性
edge dislocation
inhomogeneity
interface stress
image force
stability
