▎ 摘　　要

The mechanical response of graphene nano-ribbon under tensile loading has been investigated in this paper. Lattice symmetry dependence of the elastic response is found through molecular dynamics simulation, which fits prediction from Cauchy-Born rule very well. Concurrent brittle and ductile behaviors are observed during the failure process at elastic limit, which dominate the low and high temperature behavior respectively. The free edges in finite width ribbon help to activate bond-flip events and initialize ductile behavior, which can be explained by formation energy analysis for the Stone-Wales rotations.