适合裂尖穿越界面行为分析的断裂模拟方法研究  

On the Fracture Modeling Method for Crack Tips Penetrating Elastic Interfaces

作　　者：陈昌荣[1] 

机构地区：[1]上海工程技术大学飞行学院,上海201620

出　　处：《应用数学和力学》2014年第9期979-985,共7页Applied Mathematics and Mechanics

基　　金：国家自然科学基金(51175321)~~

摘　　要：分析了线弹性断裂力学在模拟裂尖垂直穿越弹性界面行为时存在的理论缺陷;对理想化的层状弹性材料,采用内聚力模型研究了界面前方材料的内聚强度对裂尖穿越界面行为的影响;根据有限元计算结果,讨论了内聚力模型与线弹性断裂力学在模拟裂纹垂直于界面扩展时的差别.计算结果显示,界面前方材料的内聚强度大小对裂尖穿越界面行为有重要影响,是导致内聚力模型与线弹性断裂力学模型计算结果差异的关键因素.计算结果分析表明:研究复杂材料中裂纹扩展行为时,不仅需要一个基于能量的断裂准则,还需要补加一个强度准则,内聚力模型在理论上符合这一要求.The theoretical defects of the linear elastic fracture mechanics in modeling crack tips passing through elastic interfaces were analyzed; for an idealized layered material, the cohesive zone model was applied to study the effects of the material cohesive strength ahead of the interface on the behavior of a crack perpendicularly approaching and penetrating an elastic interface; based on the finite element calculation results, the difference between the cohesive zone model and the linear elastic fracture mechanics in simulating a perpendicular crack near an elastic interface was discussed. The results show that the material cohesive strength ahead of the interface is the key factor causing the simulation difference between the cohesive zone model and the linear elastic fracture mechanics. The study gives the conclusion that, to model the crack growth in complex materials, the strength criterion is needed in addition to the traditional energy-based fracture criterion, and the cohesive zone model theoretically satisfies this requirement.

关 键 词：内聚力模型 断裂过程区 裂纹扩展准则 弹性界面 

分 类 号：O343[理学—固体力学]