Multi-scale modeling of shear banding in iron-based metallic glasses

Abstract

Multi-scale modeling approaches are developed to investigate the deformation mechanisms in iron-based metallic glasses. The shear band formation and crack propagation in the iron-based metallic glasses are investigated using a phase-field phenomenological model. The parameters which are necessary to the formulism of mesoscopic phase-field modeling, e.g., the surface energy, activation energy and elastic constants related to the formation of free-volume defects, are obtained by ab initio molecular dynamics simulations on an amorphous Fe 80Si 10B 10 model system. The important features of shear banding such as shear band width and crack propagation velocity obtained from the multi-scale modeling are consistent with those of experiments. These results demonstrate that the mechanical behaviors of bulk metallic glasses can be understood by the multi-scale modeling developed in this study.