▎ 摘　　要

The chirality-dependent mixed-mode I-II fracture toughness and crack growth angles of single-layer graphene sheets are determined using molecular dynamics (MD) simulations and the finite element (FE) method based on the boundary layer model, respectively. The carbon-carbon bond in the FE method is equivalent to a nonlinear Timoshenko beam based on the Tersoff-Brenner potential. All the results of the present FE method agree well with those of our MD simulations performed using the REBO potential. The chiral crack angles of alpha = 0 degrees (zigzag), 15 degrees, 30 degrees (or 90 degrees, armchair), and 45 degrees at different loading angles from 0 degrees ]