Quantifying the microstructural inhomogeneity of Zr₄₆Cu₄₆Al₈metallic glasses based on change ratio of polyhedral volume

The microstructural inhomogeneity of Zr46Cu46Al8metallic glasses is investigated quantitatively by molecular dynamics simulation. A parameter, the change ratio of polyhedral volume, is used to characterize the microstructural inhomogeneity in metallic glasses. Based on identifying the polyhedral volume expansion and contraction around each atom, the microstructural heterogeneity of metallic glasses can be revealed and quantified. The relation between the redistribution of the free volume and production or annihilation of defects has been established. By molecular dynamics simulations of dynamic mechanical tests, the distribution of the change ratio of polyhedral volume is correlated to dynamic heterogeneities in metallic glasses at the atomic level. Our work opens a new technologically avenue towards the characterization of microstructural inhomogeneity that affects the thermodynamics, dynamics and deformation in metallic glasses.