Athermal mechanical analysis of Stone-Wales defects in two-dimensional silica

摘要

In this paper, we investigate the influence of Stone-Wales defects on the mechanical behavior of two-dimensional silica in the absence of thermal effects. The application of the athermal quasistatic deformation method allows us to study deformation-induced non-affine rearrangements in the material, a strategy that has not yet been applied to this type of material. Applying bond switch moves to the hexagonal two-dimensional silica samples followed by energy minimization and volumetric relaxation, various athermal tensile simulations are performed in armchair and zigzag directions, which induce fracture mode I. The samples with SW defects clearly show stationary states during the fracture process. Thus, we prove a brittle-to-ductile transition, induced by the SW defect. The mechanical understanding of the influence of these local defects on the fracture behavior of two-dimensional silica contributes to explaining the yield and fracture behavior of network glasses.