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Composition effect on intrinsic plasticity or brittleness in metallic glasses.

ABSTRACT: The high plasticity of metallic glasses is highly desirable for a wide range of novel engineering applications. However, the physical origin of the ductile/brittle behaviour of metallic glasses with various compositions and thermal histories has not been fully clarified. Here we have found that metallic glasses with compositions at or near intermetallic compounds, in contrast to the ones at or near eutectics, are extremely ductile and also insensitive to annealing-induced embrittlement. We have also proposed a close correlation between the element distribution features and the plasticity of metallic glasses by tracing the evolutions of the element distribution rearrangement and the corresponding potential energy change within the sliding shear band. These novel results provide useful and universal guidelines to search for new ductile metallic glasses at or near the intermetallic compound compositions in a number of glass-forming alloy systems.

SUBMITTER: Zhao YY

PROVIDER: S-EPMC4104394 | biostudies-literature | 2014 Jul

REPOSITORIES: biostudies-literature

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Composition effect on intrinsic plasticity or brittleness in metallic glasses.

Zhao Yuan-Yun YY Inoue Akihisa A Chang Chuntao C Liu Jian J Shen Baolong B Wang Xinmin X Li Run-Wei RW

Scientific reports 20140721

The high plasticity of metallic glasses is highly desirable for a wide range of novel engineering applications. However, the physical origin of the ductile/brittle behaviour of metallic glasses with various compositions and thermal histories has not been fully clarified. Here we have found that metallic glasses with compositions at or near intermetallic compounds, in contrast to the ones at or near eutectics, are extremely ductile and also insensitive to annealing-induced embrittlement. We have ...[more]

PMID: 25043428

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