AVS 64th International Symposium & Exhibition
    2D Materials Focus Topic Monday Sessions
       Session 2D+EM+MI+MN-MoM

Paper 2D+EM+MI+MN-MoM9
Mechanical Properties of Polycrystalline and Defective Graphene

Monday, October 30, 2017, 11:00 am, Room 15

Session: Properties of 2D Materials including Electronic, Magnetic, Mechanical, Optical, and Thermal Properties
Presenter: Joseph Gonzales, University of South Florida
Authors: J.M. Gonzales, University of South Florida
I.I. Oleynik, University of South Florida
J.T. Willman, University of South Florida
R. Perriot, Los Alamos National Laboratory
Correspondent: Click to Email
Experimental investigation of mechanical properties indicates that the polycrystalline graphene grown by chemical vapor deposition is as strong as pristine. Recent experiments involving nanoindentation of graphene have also demonstrated counterintuitive increasing of Young’s modulus with increasing concentrations of point defects. Using accurate description of interatomic interactions provided by novel screened environment-dependent bond order, (SED-REBO) potential, we performed large-scale molecular dynamics investigations of mechanical properties of polycrystalline and defective graphene samples under conditions mimicking nano-indentation AFM experiments. The atomically resolved characterization of the stress and strain distributions under indenter are used to understand fundamental mechanisms of graphene strength and failure. The breaking strength, the crack initiation and propagation are investigated as a function of the grain boundary structure, grain size distribution, concentration of point defects as well as the position of the indenter in respect to these extended and point defects.