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Soft spots and their structural signature in a metallic glass.

ABSTRACT: In a 3D model mimicking realistic Cu64Zr36 metallic glass, we uncovered a direct link between the quasi-localized low-frequency vibrational modes and the local atomic packing structure. We also demonstrate that quasi-localized soft modes correlate strongly with fertile sites for shear transformations: geometrically unfavored motifs constitute the most flexible local environments that encourage soft modes and high propensity for shear transformations, whereas local configurations preferred in this alloy, i.e., the full icosahedra (around Cu) and Z16 Kasper polyhedra (around Zr), contribute the least.

SUBMITTER: Ding J

PROVIDER: S-EPMC4191783 | biostudies-other | 2014 Sep

REPOSITORIES: biostudies-other

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Soft spots and their structural signature in a metallic glass.

Ding Jun J Patinet Sylvain S Falk Michael L ML Cheng Yongqiang Y Ma Evan E

Proceedings of the National Academy of Sciences of the United States of America 20140916 39

In a 3D model mimicking realistic Cu64Zr36 metallic glass, we uncovered a direct link between the quasi-localized low-frequency vibrational modes and the local atomic packing structure. We also demonstrate that quasi-localized soft modes correlate strongly with fertile sites for shear transformations: geometrically unfavored motifs constitute the most flexible local environments that encourage soft modes and high propensity for shear transformations, whereas local configurations preferred in thi ...[more]

PMID: 25228762

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