准脆性材料中椭圆形微裂纹的生长与演化  

The Growth and Evolution of Elliptical Micro-cracks in Quasi-brittle Materials

作　　者：方敏杰[1] 任会兰[1] 宁建国[1] 

机构地区：[1]北京理工大学爆炸科学与技术国家重点实验室,北京100081

出　　处：《材料工程》2013年第2期35-39,共5页Journal of Materials Engineering

基　　金：国家自然科学基金资助项目(11172045)

摘　　要：微裂纹的生长与演化是导致准脆性材料损伤及破坏的本质,本工作对承载过程中准脆性材料内部的椭圆形微裂纹的生长与演化规律进行研究。采用复势函数求解受远场载荷作用下代表性单元中椭圆形微裂纹的变形,讨论了椭圆形微裂纹初始取向的变化对微裂纹尺寸增长的影响,并结合微裂纹扩展准则推导出损伤开始时的临界应力条件。基于翼型裂纹扩展过程的能量守恒关系,建立了损伤阶段的本构关系。Growth and evolution of micro-cracks are the mechanism of damage and failure for quasi- brittle materials. The principle for growth and evolution of micro-cracks in quasic-brittle material sub- jected to loading is studied. The analytical solution is given for the growth of elliptical micro-cracks in elastic deformation stage by the method of complex potential functions. The critical stress condition for the starting damage is derived based on micro-crack growth criterion. The constitutive relation is developed based on the conservation of energy during the wing-crack propagating.

关 键 词：微裂纹 损伤 演化 

分 类 号：O347.1[理学—固体力学]