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Hardening of shear band in metallic glass.

ABSTRACT: Strain hardening, originating from defects such as the dislocation, avails conventional metals of high engineering reliability in applications. However, the hardenability of metallic glass is a long-standing concern due to the lack of similar defects. In this work, we carefully examine the stress-strain relationship in three bulk monolithic metallic glasses. The results show that hardening is surely available in metallic glasses if the effective load-bearing area is considered instantly. The hardening is proposed to result from the remelting and ensuing solidification of the shear-band material under a hydrostatic pressure imposed by the normal stress during the shear banding event. This applied-pressure quenching densifies the metallic glass by discharging the free volume. On the other hand, as validated by molecular dynamics simulations, the pressure promotes the icosahedral short-range order. The densification and icosahedral clusters both contribute to the increase of the shear strength and therefore the hardening in metallic glasses.

SUBMITTER: Wang JG

PROVIDER: S-EPMC5539228 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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Hardening of shear band in metallic glass.

Wang J G JG Hu Y C YC Guan P F PF Song K K KK Wang L L Wang G G Pan Y Y Sarac B B Eckert J J

Scientific reports 20170801 1

Strain hardening, originating from defects such as the dislocation, avails conventional metals of high engineering reliability in applications. However, the hardenability of metallic glass is a long-standing concern due to the lack of similar defects. In this work, we carefully examine the stress-strain relationship in three bulk monolithic metallic glasses. The results show that hardening is surely available in metallic glasses if the effective load-bearing area is considered instantly. The har ...[more]

PMID: 28765652

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