TY - JOUR

T1 - Hardening of shear band in metallic glass

AU - Wang, J. G.

AU - Hu, Y. C.

AU - Guan, P. F.

AU - Song, K. K.

AU - Wang, L.

AU - Wang, G.

AU - Pan, Y.

AU - Sarac, Baran

AU - Eckert, Jürgen

PY - 2017/8/1

Y1 - 2017/8/1

N2 - 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.

AB - 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.

U2 - 10.1038/s41598-017-07669-9

DO - 10.1038/s41598-017-07669-9

M3 - Article

VL - 2017

JO - Scientific reports (London : Nature Publishing Group)

JF - Scientific reports (London : Nature Publishing Group)

SN - 2045-2322

IS - 7

M1 - 7076

ER -