| Graphene is an one-atom-thick planar sheet of covalently bonded carbon atomswhich are tightly packed in a honeycomb crystal lattice. Due to its superiormechanical, electrical, thermal and optical properties, graphene has very broadapplication prospects. The study of its performance, such as mechanics, is a researchhot spot at home and abroad. Graphene is a kind of typical two-dimensionalnanostructures, under the effect of surface tension or other external load, graphenesheets are easy to occur buckling and wrinkling, thus the properties of graphene arechanged. For this reason, much attention was focused on the stability of the graphene.We are direct towards the elastic buckling of the perfect and defected graphene sheetsbased on molecular structural mechanics approach as well as the classical plate theory.Elastic buckling behavior of single-layered and double-layered perfect graphenesheets was studied. Elastic buckling of single-layer graphene sheets with twodifferent boundary conditions(two sides was constrained and other sides kept free,four edges simply supported) was studied respectively used finite element methodbased on molecular structural mechanics. The size effect of elastic buckling stress ofsingle-layered graphene sheets was studied. Further, the effects of chiral as well asboundary conditions were investigated. Compaired to the classical buckling theoryof plate, fitting buckling stress formulas of graphene with two different boundaryconditions are obtained respectively and have a good consistency of the resultsobtained by molecular structural mechanics simulation. Elastic buckling behavior ofdouble-layered graphene was studied based on Lennard-Jones potential. Elasticbuckling of graphene under cantilever and simply supported conditions, size andchirality was investigated, and compared with the results of single-layered graphene,the results showed that Van der Waals force has a very important influence onbuckling stress. Our results were compared with the results used other methods and found they are consistent.Elastic buckling of defected graphene sheets was studied. The influence of atomvacancy defect and two different types of Stone-Wales defects on buckling behaviorof graphene was researched. Further, the influence of location and density of defectson buckling stress of graphene was investigated. The results showed that atomvacancy defect always decreases the buckling stresses of both zigzag and armchairgraphene sheets. However, the influence of Stone-Wales defects on the buckling ofgraphene associated with the chiral of graphene. |
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