Nonaffine Strains Control Ductility of Metallic Glasses

Hui Wang, Wojciech Dmowski, Yang Tong, Zengquan Wang, Yoshihiko Yokoyama, Jittisa Ketkaew, Jan Schroers, and Takeshi Egami

Phys. Rev. Lett. 128, 155501 – Published 15 April 2022

Abstract

The origin of limited plasticity in metallic glasses is elusive, with no apparent link to their atomic structure. We propose that the response of the glassy structure to applied stress, not the original structure itself, provides a gauge to predict the degree of plasticity. We carried out high-energy x-ray diffraction on various bulk metallic glasses (BMGs) under uniaxial compression within the elastic limit and evaluated the anisotropic pair distribution function. We show that the extent of local deviation from the affine (uniform) deformation in the elastic regime is strongly correlated with the plastic behavior of BMGs beyond yield, across chemical compositions and sample history. The results suggest that the propensity for collective local atomic rearrangements under stress promotes plasticity.

Received 21 June 2021
Revised 8 February 2022
Accepted 20 March 2022

DOI:https://doi.org/10.1103/PhysRevLett.128.155501

Physics Subject Headings (PhySH)

Ductility Plasticity Structural properties

Metallic glasses

Condensed Matter, Materials & Applied Physics

Authors & Affiliations

Hui Wang¹, Wojciech Dmowski¹, Yang Tong¹, Zengquan Wang¹, Yoshihiko Yokoyama³, Jittisa Ketkaew⁴, Jan Schroers⁴, and Takeshi Egami ^1,2,5,*

¹Department of Materials Science and Engineering, University of Tennessee, Knoxville, Tennessee 37996, USA
²Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
³Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
⁴Department of Mechanical Engineering and Materials Science, Yale University, New Haven, Connecticut 06511, USA
⁵Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA