Effect of grain boundary and defect on mechanical properties of bicrystalline graphene

The effects of grain boundary (GB) and defect on the deformation behaviors of graphene under tension or compression in directions perpendicular (x-axis) or parallel (y-axis) to GB are investigated by molecular dynamics (MD) simulation. The results show that the bicrystalline graphene can sustain more load under tension along y-axis than along x-axis, and that regardless of tensile directions, the yield strength of bicrystalline graphene with high misorientation angle is higher than that with low angle. Furthermore, we found that the effect of GB on the deformation behavior of graphene under compression strain along x-axis is more obvious than that along y-axis.