Structural Aspects of Deformation Defects in Bulk Metallic Glasses

TL;DR

This paper introduces a novel anisotropic pair distribution function method to directly observe and characterize deformation defects in bulk metallic glasses, linking microscopic structural features to macroscopic mechanical behavior.

Contribution

It develops a new experimental approach to directly analyze the structural features of shear transformation zones in BMGs, overcoming limitations of previous fitting methods.

Findings

Direct observation of deformation defects in BMGs

Link between mechanical response and defect properties

Enhanced understanding of deformation mechanisms

Abstract

Mechanical behaviors of bulk metallic glasses (BMGs) including heterogeneous and homogeneous deformation are interpreted by phenomenological shear transformation zones (STZs) model. Currently, information about STZs, i.e. size and density, is only extracted by fitting model equation to the data obtained from macroscopic mechanical tests. This is inadequate since structural features of STZs theory cannot be assessed. Here, we develop anisotropic pair distribution function (PDF) method for directly characterizing mechanical response of deformation defects. Our results reveal the physical picture of deformation defects in BMGs and also provide direct experimental observation of a link between mechanical deformation and intrinsic properties of deformation defects in BMGs.