Evaluation of the Stress-Strain of Single-Layer Graphene Sheet Including a Crack

Abstract

Graphene is extremely thin, which exhibits extraordinary mechanical, physical and electrical properties, such that there are applications for this material in batteries and flexible displays. However, during the fabrication of commercial graphene devices, defects such as impurities and vacancies inevitably occur and the resulting cracks or notches can deteriorate the performance of graphene-based structures. Thus, it is necessary to understand the mechanical properties of graphene sheets including cracks so as to design healthy graphene-based structures. The present study investigated the effects of cracks (at various positions, distances and angles) on the strength of graphene. Four initial positions were considered in conjunction with uniaxial tensile loading, along with nine different distances and three initial angles. It was found that a crack located at the top center of the sheet represents the most vulnerable stress point, while a crack located further than one quarter of the sheet from the loading point had the greatest effect on the stress. In addition, the maximum stress was obtained in conjunction with a crack inclined at 45° relative to the loading direction. These results are expected to assist in the future evaluation for the safety usage of graphene sheets.