Substantially enhanced plasticity of bulk metallic glasses by densifying local atomic packing.

ABSTRACT: Introducing regions of looser atomic packing in bulk metallic glasses (BMGs) was reported to facilitate plastic deformation, rendering BMGs more ductile at room temperature. Here, we present a different alloy design approach, namely, doping the nonmetallic elements to form densely packed motifs. The enhanced structural fluctuations in Ti-, Zr- and Cu-based BMG systems leads to improved strength and renders these solutes' atomic neighborhoods more prone to plastic deformation at an increased critical stress. As a result, we simultaneously increased the compressive plasticity (from ∼8% to unfractured), strength (from ∼1725 to 1925 MPa) and toughness (from 87 ± 10 to 165 ± 15 MPa√m), as exemplarily demonstrated for the Zr₂₀Cu₂₀Hf₂₀Ti₂₀Ni₂₀ BMG. Our study advances the understanding of the atomic-scale origin of structure-property relationships in amorphous solids and provides a new strategy for ductilizing BMG without sacrificing strength.

SUBMITTER: Wu Y 

PROVIDER: S-EPMC8590062 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature