Influence of Crystalline Nanoprecipitates on Shear-Band Propagation in Cu-Zr Based Metallic Glasses

TL;DR

This study explores how crystalline nanoprecipitates influence shear-band behavior in Cu-Zr metallic glasses, revealing mechanisms like dissolution, wrapping, blocking, and slip transfer, depending on precipitate properties.

Contribution

It provides a combined experimental and computational analysis of nanoprecipitate interactions with shear bands, introducing a qualitative mechanism map based on precipitate size, density, and critical stress.

Findings

Shear bands can dissolve, wrap around, or be blocked by precipitates.

Slip transfer occurs if the crystalline phase has low yield strength.

A qualitative mechanism map categorizes interaction processes.

Abstract

The interaction of shear bands with crystalline nanoprecipitates in Cu-Zr-based metallic glasses is investigated by a combination of high-resolution TEM imaging and molecular-dynamics computer simulations. Our results reveal different interaction mechanisms: Shear bands can dissolve precipitates, can wrap around crystalline obstacles, or can be blocked depending on size and density of the precipitates. If the crystalline phase has a low yield strength, we also observe slip transfer through the precipitate. Based on the computational results and experimental findings, a qualitative mechanism map is proposed that categorizes the various processes as a function of the critical stress for dislocation nucleation, precipitate size, and distance.