WIT Press


On The Mechanism Of Deformation Localization And Homogeneous Flow In Bulk Metallic Glasses

Price

Free (open access)

Paper DOI

10.2495/HPSM160211

Volume

166

Pages

10

Page Range

235 - 244

Published

2017

Size

409 kb

Author(s)

J. C. Li, X. W. Chen, F. L. Huang

Abstract

A modified coupled thermo-mechanical constitutive model for bulk metallic glasses (BMGs) is deduced in the present manuscript. Besides, a failure criterion of critical free volume concentration is introduced. The constitutive model as well as the failure criterion is implemented into the LS-DYNA commercial software through the user material subroutine (UMAT). Finite element method (FEM) simulations for different initial material temperatures and strain rates are conducted, and the evolutions of material parameter as well as the corresponding macroscopic mechanical behavior of material are analyzed. Related analysis shows that at room temperature, the deformation and failure characteristics in the shear band zones of BMGs are significantly different from that in the matrix, and consequently high deformation localization occurs. Comparatively, within the supercooled liquid region, the mechanical behaviors in the shear band zones and that in the matrix are similar to each other, and thus BMGs usually behave as homogeneous flow.

Keywords

bulk metallic glass, deformation, constitutive model, FEM simulation