Computer simulation of the strong surface effects on deformation behaviors of metallic glass nanowires

Size effects on deformation behaviors of metallic glass (MG) nanowires are found to be associated with their surface imperfections from phase-field modeling. Necking instead of shear banding is the dominant deformation mode in MG nanowire with diameter d < 100 nm, suggesting that nucleation and growth of the flow defects at the nanowire surface could be the deformation mechanism. The surface effect manifests itself by the finite-size scaling for the fracture strength and the critical intrinsic surface defect density.