Strength and fracture behavior of graphene grain boundaries: effects of temperature, inflection, and symmetry from molecular dynamics

Abstract

We present a molecular dynamic simulation on the mechanical strength and fracture behavior of graphene grain boundaries (GBs). The intrinsic strength, critical failure strain, and failure mechanism of graphene GBs mainly rely on the temperature and inflection angle, whereas the Young's modulus does not vary significantly with either temperature or boundary configuration. The overall intrinsic strengths of inflected GBs can be correlated with infection angle by a linear term, which is irrelevant to the system temperature. The initial failure sites of GBs locate either on the boundary line or inside the domain at high temperature.