| AVS 58th Annual International Symposium and Exhibition | |
| Graphene and Related Materials Focus Topic | Wednesday Sessions |
| Session GR+MN-WeM |
| Session: | Graphene: Mechanical and Thermal Properties, Graphene MEMS and NEMS |
| Presenter: | Romain Perriot, University of South Florida |
| Authors: | R. Perriot, University of South Florida Y. Lin, University of South Florida X. Gu, Aalto University School of Science and Technology, Finland V.V. Zhakhovsky, University of South Florida I.I. Oleynik, University of South Florida |
| Correspondent: | Click to Email |
Recent nanoindentation experiments on graphene have revealed its exceptional strength, making it an excellent candidate for the design of nano devices such as MEMS and pressure sensors. Therefore, it is critical to understand the mechanical properties of graphene, and its response to a wide range of loading pressures beyond the elastic regime. In this work we performed molecular dynamics (MD) simulations of the nanoindentation of graphene membranes by a spherical indenter. The indentation curves (load vs. indentation depth) obtained from simulations revealed two regimes of response: linear for smaller, and non-linear for larger indentation depths respectively. The MD results are in good agreement with the theory of elastic plates and recent experiments. Using the kinetic theory of fracture, we were able to determine the breaking strength of graphene and its dependence on the indenter radius. MD simulations also provided an atomic-scale description of the breaking process, which occurs through crack formation and propagation in graphene.