基于随机分布代表性体积的颗粒增强复合材料拉伸断裂破坏模拟  

Simulation of Tensile Fracture Failure of Randomly Distributed Particle Reinforced Composites with Representative Volume Element

作　　者：丁桥华 宁志华 DING Qiaohua;NING Zhihua(MOE Key Laboratory of Disaster Forecast and Control in Engineering,School of Mechanics and Construction Engineering,Jinan University,Guangzhou 510632,China)

机构地区：[1]暨南大学力学与建筑工程学院,重大灾害与控制教育部重点实验室,广东广州510632

出　　处：《材料科学与工程学报》2021年第5期783-790,共8页Journal of Materials Science and Engineering

基　　金：国家自然科学基金资助项目(11302083);广东省自然科学基金资助项目(2018A0303130128)。

摘　　要：为研究组分材料性能对材料断裂破坏行为的影响,基于计算细观力学,建立施加周期性边界条件的代表性体积单元,对随机分布颗粒增强复合材料的拉伸断裂破坏进行数值模拟。为选取更具代表性的体积单元,采用径向分布函数和平均近邻距离变异系数两种统计方法对生成的随机分布细观结构进行评估。并在此基础上,对复合材料的有效弹性常数进行分析,以验证所选代表性体积单元的有效性。利用选定的代表性体积单元,运用扩展有限元方法对Al_(2)O_(3)/TiB_(2)陶瓷复合材料的拉伸断裂破坏进行了数值模拟,重点讨论了颗粒断裂韧性、界面粘结强度对裂纹萌生及扩展的影响。研究结果表明,不同的颗粒断裂韧性下,复合材料的断裂行为基本一致;界面粘结强度对裂纹的萌生及扩展路径影响较为显著,破坏载荷的变化随界面粘结强度的增加分为三个不同阶段。对于Al_(2)O_(3)/TiB_(2)陶瓷复合材料,当界面粘结强度为0.6~60MPa时,可兼顾界面的韧性和复合材料的断裂韧性。To investigate effects of component properties on material failure behavior,numerical analysis of the tensile fracture failure of randomly distributed particle reinforced composites was carried out.The whole process was based on computational micromechanics by using a representative volume element(RVE)with periodic boundary conditions.The generated microstructures with randomly distributed particles were evaluated statistically with the radial distribution function and the coefficient of variation of nearest-neighbor distance to perform a final selection of RVEs.For further validation,the effective elastic properties of the composites were predicted and compared with the results in the literatures.Numerical simulation was conducted on the tensile fracture failure behavior of Al_(2)O_(3)/TiB_(2) ceramic composites by using the extended finite element method.During the simulation,the effects of reinforcement toughness and interfacial bonding strength on the fracture performance of the composites under uniaxial tension were stressed.The results showed that,the failure performances of the composite are similar even for different fracture toughness of the particle phase.However,the interfacial bonding strength levels have significant influence on the crack initiation and propagation path in the composite.The variation of the failure loads with increasing interfacial bonding strength levels can be divided into three phases.For Al_(2)O_(3)/TiB_(2) and its bonding strength ranging from 0.6 to 60 MPa,a proper balance could be maintained between interfacial bonding toughness and the fracture toughness of the whole composite.

关 键 词：颗粒增强 随机分布 代表性体积单元 扩展有限元 界面粘结强度 

分 类 号：TB332[一般工业技术—材料科学与工程]