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Rate dependent of strength in metallic glasses at different temperatures.

ABSTRACT: The correlation between the strength at the macroscale and the elastic deformation as well as shear cracking behavior at the microscale of bulk metallic glasses (BMGs) is investigated. The temperatures of 298?K and 77?K as well as the strain rate ranging from 10(-6) s(-1) to 10(-2) s(-1) are applied to the BMGs, in which the mechanical responses of the BMGs are profiled through the compression tests. The yield strength is associated with the activation of the elementary deformation unit, which is insensitive to the strain rate. The maximum compressive strength is linked to the crack propagation during shear fracture process, which is influenced by the strain rate. The cryogenic temperature of 77?K significantly improves the yield strength and the maximum compressive strength of the BMGs.

SUBMITTER: Wang YW

PROVIDER: S-EPMC4897709 | biostudies-other | 2016

REPOSITORIES: biostudies-other

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Rate dependent of strength in metallic glasses at different temperatures.

Wang Y W YW Bian X L XL Wu S W SW Hussain I I Jia Y D YD Yi J J Wang G G

Scientific reports 20160608

The correlation between the strength at the macroscale and the elastic deformation as well as shear cracking behavior at the microscale of bulk metallic glasses (BMGs) is investigated. The temperatures of 298 K and 77 K as well as the strain rate ranging from 10(-6) s(-1) to 10(-2) s(-1) are applied to the BMGs, in which the mechanical responses of the BMGs are profiled through the compression tests. The yield strength is associated with the activation of the elementary deformation unit, which i ...[more]

PMID: 27270688

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