压电螺型位错和含界面裂纹圆形夹杂的电弹干涉效应  

Electroelastic Interaction Between a Piezoelectric Screw Dislocation and a Circular Inhomogeneity With Interfacial Cracks

作　　者：刘又文[1] 方棋洪[1] 

机构地区：[1]湖南大学工程力学系,长沙410082

出　　处：《应用数学和力学》2004年第12期1305-1312,共8页Applied Mathematics and Mechanics

基　　金：国家自然科学基金资助项目(10272009);湖南省自然科学基金资助项目(02JJY2014)

摘　　要：　研究了在无穷远反平面剪切和面内电场共同作用下压电材料基体中一个压电螺型位错与含界面裂纹圆形弹性夹杂的电弹耦合干涉作用·　运用复变函数方法,获得了该问题的一般解答·　作为典型算例,求出了界面含一条裂纹时,基体和夹杂区域复势函数的封闭形式解以及裂纹尖端应力和电位移场强度因子·　应用扰动技术和广义Peach＿Koehler公式,导出了位错力的解析表达式·　数值结果表明,界面裂纹对压电螺型位错与夹杂的干涉具有强烈扰动效应,当裂纹长度达到临界值时,可以改变其干涉机理·　同时。A piezoelectric screw dislocation in the matrix interacting with a circular inhomogeneity with interfacial cracks under antiplane shear and in_plane electric loading at infinity was dealt with. Using complex variable method, a general solution to the problem was presented. For a typical case, the closed form expressions of complex potentials in the inhomogeneity and the matrix regions and the electroelastic field intensity factors were derived explicitly when the interface contains single crack. The image force acting on the piezoelectric screw dislocation was calculated by using the perturbation technique and the generalized Peach_Koehler formula. As a result, numerical analysis and discussion show that the perturbation influence of the interfacial crack on the interaction effects of the dislocation and the inhomogeneity is significant which indicates the presence of the interfacial crack will change the interaction mechanism when the length of the crack goes up to a critical value. It is also shown that soft inhomogeneity can repel the dislocation due to their intrinsic electromechanical coupling behavior.

关 键 词：压电材料 位错力 界面裂纹 螺型位错 

分 类 号：O343.7[理学—固体力学]