Atomic-scale heterogeneity in large-plasticity Cu-doped metallic glasses

By using nanoindentation techniques combined with transmission electron microscope, wide-/small-angle X-ray scattering, and three-dimensional atom probe tomography, the sub-nanometer- to nanometer-length-scale structural heterogeneity due to the precipitation of Co(Fe)-rich clusters was observed in [(Co0.7Fe0.3)(0.68)B0.219Si0.051Nb0.05](100-x)Cu-x (x = 0.5) metallic glasses. Such short-range ordered structure promotes energy dissipation during deformation via regulating intrinsic elastic constants and hardness at the mesoscale, which contributes to the improved compressive plasticity of Cu-doped (Fe, Co)-based metallic glasses. Our work provides new evidence on atomic-scale heterogeneity in Cu-doped metallic glasses from the aspects of topological orders and microscopic mechanical responses. (C) 2019 Elsevier B.V. All rights reserved.