双悬臂梁试件裂纹动态扩展的准静态数值分析  

A quasi-static numerical analysis of crack dynamic propagation in double cantilever beam specimens

作　　者：吴庆欣 肖毅[1] 薛元德[1] WU Qingxin;XIAO Yi;XUE Yuande(School of Aerospace Engineering and Applied Mechanics, Tongji University, Shanghai 200092, China)

机构地区：[1]同济大学航空航天与力学学院,上海200092

出　　处：《复合材料学报》2019年第5期1179-1188,共10页Acta Materiae Compositae Sinica

基　　金：国家自然科学基金(11832014)

摘　　要：本文采用双悬臂梁(DCB)试件研究了复合材料层合板层间插入韧性胶膜(Interleaf)层的Ⅰ型断裂行为。试验结果表明,含和不含Interleaf层试件分别呈现脆性非稳态和脆性稳态分层扩展特性。针对非稳定裂纹扩展问题,依据动态断裂力学中应变能释放率与动能变化率的关系,提出了以断裂韧性值G_(IC)变化来抵消动能变化对裂纹扩展过程影响的准静态分析方法,根据试验中裂纹扩展的韧性变化,推导出适用于准静态裂纹扩展模拟的等效韧性G_(IC)~*,利用ABAQUS平台和虚裂纹闭合技术(VCCT)建立了三维有限元计算模型;实现了从起裂到止裂的整个裂纹动态扩展过程的数值模拟,揭示了非稳定裂纹扩展过程中一些复杂的力学现象。The mode I interlaminar fracture toughness of composite laminates with epoxy interleaf was studied in the double cantilever beam(DCB)tests.Brittle unstable and stable delaminations were observed in the specimens with and without interleaf respectively.For the unstable crack growth,based on dynamic fracture mechanics,the relation between strain energy release rate and the change of kinetic energy was analyzed.A static simulation method for dynamic crack growth was proposed,which transformed the change of kinetic energy into the change of input fracture toughness(GIC*).GIC*was calculated according to the evolution of fracture resistance in the tests and input into ABAQUS for the simulation of crack growth using virtual crack closure technique(VCCT).A three-dimensional finite element model was constructed to simulate the dynamic delamination growth from crack onset to arrest,and the complex mechanical behavior in the unstable crack growth was studied.

关 键 词：断裂动力学 有限元分析 应变能释放率 非稳定裂纹扩展 虚拟裂纹闭合技术 

分 类 号：TB332[一般工业技术—材料科学与工程]