# Rejuvenation and Shear-Banding in model amorphous solids

## TL;DR

This study investigates local yield stress and shear banding in amorphous solids, revealing how plastic events influence local softness and relate to the material's transition from brittle to ductile behavior.

## Contribution

It introduces a detailed measurement of local yield stress in amorphous solids and links plastic events to the emergence of shear bands and material ductility.

## Key findings

- Plastic events erase initial structural memory.
- Shear bands are softer in early stages.
- Yield stress relates to supercooled liquid states.

## Abstract

We measure the local yield stress, at the scale of small atomic regions, in a deeply quenched two-dimensional glass model undergoing shear banding in response to athermal quasistatic (AQS) deformation. We find that the occurrence of essentially a single plastic event suffices to bring the local yield stress distribution to a well-defined value for all strain orientations, thus essentially erasing the memory of the initial structure. It follows that in a well-relaxed sample, plastic events cause the abrupt (nucleation-like) emergence of a local softness contrast and thus precipitate the formation of a band, which, in its early stages, is measurably softer than the steady-state flow. Moreover, this postevent yield stress ensemble presents a mean value comparable to that of the inherent states of a supercooled liquid around the mode-coupling temperature $T_{\rm MCT}$. This, we argue, explains that the transition between brittle and ductile yielding in amorphous materials occurs around a comparable parent temperature. Our data also permit to capture quantitatively the contributions of pressure and density changes and demonstrate unambiguously that they are negligible compared with the changes of softness caused by structural rejuvenation.