Effect of Vacancy Defects on the Young＇s Modulus and Fracture Strength of Graphene： A Molecular Dynamics Study  

作　　者：朱剑 贺明 邱枫 

机构地区：[1]State Key Laboratory of Molecular Engineering of Polymers,Department of Macromolecular Science,Fudan University,Shanghai 200433,China

出　　处：《Chinese Journal of Chemistry》2012年第7期1399-1404,共6页中国化学（英文版）

摘　　要：The Young＇s modulus of graphene with various rectangular and circular vacancy defects is investigated by molecular dynamics simulation. By comparing with the results calculated from an effective spring model, it is demonstrated that the Young＇s modulus of graphene is largely correlated to the size of vacancy defects perpendicular to the stretching direction. And a linear reduction of Young＇s modulus with the increasing concentration of monoatomic-vacancy defects （Le., the slope of =0.03） is also observed. The fracture behavior of graphene, including the fracture strength, crack initiation and propagation are then studied by the molecular dynamics simulation, the effective spring model, and the quantized fracture mechanics. The blunting effect of vacancy edges is demonstrated, and the characterized crack tip radius of 4.44 A is observed.The Young＇s modulus of graphene with various rectangular and circular vacancy defects is investigated by molecular dynamics simulation. By comparing with the results calculated from an effective spring model, it is demonstrated that the Young＇s modulus of graphene is largely correlated to the size of vacancy defects perpendicular to the stretching direction. And a linear reduction of Young＇s modulus with the increasing concentration of monoatomic-vacancy defects （Le., the slope of =0.03） is also observed. The fracture behavior of graphene, including the fracture strength, crack initiation and propagation are then studied by the molecular dynamics simulation, the effective spring model, and the quantized fracture mechanics. The blunting effect of vacancy edges is demonstrated, and the characterized crack tip radius of 4.44 A is observed.

关 键 词：GRAPHENE mechanical properties molecular dynamics simulation vacancy defect 

分 类 号：TB383[一般工业技术—材料科学与工程] TG111.4[金属学及工艺—物理冶金]