单晶硅力学性能及尺寸效应的离散元模拟  

Study on Mechanics Properties and Size Effect of Monocrystalle Silicon Using Discrete Element Method

作　　者：姜胜强[1] 谭援强[1] 李才[1] 杨冬民[1] 

机构地区：[1]湘潭大学,湘潭411105

出　　处：《中国机械工程》2010年第5期589-594,共6页China Mechanical Engineering

基　　金：国家自然科学基金资助项目(50875224);教育部新世纪优秀人才支持计划资助项目(NCET06-0708)

摘　　要：通过建立紧密连接且随机分布在指定区域内的圆盘形颗粒离散单元的力学模型来研究单晶硅的力学性能,并采用不同尺寸的离散元模型研究力学性能尺寸效应。结果表明:泊松比、单轴抗压强度、弹性模量以及断裂韧性的尺寸效应不明显,弯曲强度则随着模型尺寸的增大而减小。建立了连续体经典断裂力学有限宽板条单边直裂纹的离散元力学模型,改变初始裂纹长度进行模拟得到的结果与单边切口梁模拟结果及文献报道的试验值一致。The mechanics models formed by packed circular discrete elements and randomly distributed in a specified region were used to investigate the mechanics properties of monocrystalle-silicon,and some different sizes of discrete element model were carried out to study the size effect of mechanics properties.The simulation results suggest that there is no obvious size effect for Poisson＇s ratio,compressive strength and Young＇s modulus and fracture toughness.However,the value of flexural strength decreases with the increasing of the model size.The discrete element model of classical continuum fracture mechanics was used to simulate the fracture process of single edge vertical crack plate with finite-width under tensile stress in infinite distance.The simulation results which obtained by changing the initiate crack length of model are just the same with the simulation results of single edge notched bending（SENB） and the experimental values reported in other literatures.

关 键 词：单晶硅 力学特性 模拟 离散元法 

分 类 号：TG58[金属学及工艺—金属切削加工及机床]