Enhancing rejuvenation of metallic glass via vibration-superimposed elastic loads

Abstract

Structural rejuvenation significantly improves the plasticity of metallic glasses, though understanding its atomic mechanisms and identifying effective processing methods remain challenging. In this study, we investigate the effects of vibration-superimposed elastic loading on the structure and properties of metallic glasses through combined experiments and molecular dynamics simulations. The results demonstrate that superimposing vibration during elastic loading enhances structural rejuvenation and plasticity beyond what is achieved by elastic loading alone. Molecular dynamics simulations reveal that superimposed vibration increases atomic mobility and promotes local structural excitations (LSEs), which drive micro-plastic deformation entirely within the elastic regime. These LSEs facilitate the transformation of densely packed icosahedral (ICO)-like Voronoi polyhedron (VP) into mixed and crystal-like VPs, accompanied by an increase in excess free volume and structural disorder. Additionally, the redistribution of shear stress between ICO-like and non-ICO regions under superimposed vibration further promotes localized stress relaxation and plastic rearrangement. Overall, our findings demonstrate that vibration-superimposed elastic loading effectively induces atomic-level structural rejuvenation and enhances the plasticity of metallic glasses at room temperature, providing a promising strategy for improving their mechanical performance.