Yielding in multi-component metallic glasses: Universal signatures of elastic modulus heterogeneities

TL;DR

This study reveals universal patterns in elastic heterogeneity and percolation behavior during yielding in Ni-based multi-component metallic glasses, highlighting scale-free characteristics and critical scaling across different compositions.

Contribution

It demonstrates that elastic modulus heterogeneities and their percolation signatures are universal features in multi-component metallic glasses during yielding, regardless of composition.

Findings

Elastic heterogeneity grows via percolation of soft clusters

Universal scale-free percolation signatures are observed

Correlation length and cluster size diverge prior to yielding

Abstract

Sheared multi-component bulk metallic glasses are characterized by both chemical and structural disorder that define their properties. We investigate the behavior of the local, microstructural elastic modulus across the plastic yielding transition in six Ni-based multi-component glasses, that are characterized by compositional features commonly associated with solid solution formability. We find that elastic modulus fluctuations display consistent percolation characteristics pointing towards universal behavior across chemical compositions and overall yielding sharpness characteristics. Elastic heterogeneity grows upon shearing via the percolation of elastically soft clusters within an otherwise rigid amorphous matrix, confirming prior investigations in granular media and colloidal glasses. We find clear signatures of percolation transition with spanning clusters that are universally characterized by scale-free characteristics and critical scaling exponents. The spatial correlation length and mean cluster size tend to diverge prior to yielding, with associated critical exponents that exhibit fairly weak dependence on compositional variations as well as macroscopic stress-strain curve details.