Evolution of the spatial heterogeneity of metallic glasses and its correlation with the macroscopic visco-plasticity

Amorphous alloys (also known as metallic glasses) have no long-range order as crystalline counterparts, thus lacking traditional defects such as dislocations and grain boundaries to facilitate plastic deformation and strain hardening mechanisms. Instead, they have intrinsic hierarchical spatial heterogeneity inherited from the material preparation processes. More importantly, this spatial heterogeneity evolves with temperature and stress fields. In this study, we propose a chemo-mechanical constitutive law for metallic glasses that can describe the evolution of their spatial heterogeneity and establish the connection between this evolution with the macroscopic plastic deformation. Furthermore, our constitutive law reveals the underlying micro-mechanisms of metallic glasses under creep, relaxation, and fatigue.