Effect of pinning on the yielding transition of amorphous solids

TL;DR

This study uses simulations to explore how pinning particles in amorphous solids affects their yielding behavior, revealing increased localization and a transition from avalanche-like to homogeneous yielding as pinning concentration rises.

Contribution

It provides new insights into the impact of particle pinning on the spatial characteristics and nature of yielding in amorphous materials.

Findings

Higher pinning concentration leads to more localized plastic activity.

Stress drops decrease with increased pinning.

Yielding shifts from avalanche-like to homogeneous with more pinning.

Abstract

Using numerical simulations, we have studied the yielding response, in the athermal quasi static limit, of a model amorphous material having inclusions in the form of randomly pinned particles. We show that, with increasing pinning concentration, the plastic activity becomes more spatially localized, resulting in smaller stress drops, and corresponding increase in the magnitude of strain where yielding occurs. We demonstrate that, unlike the spatially heterogeneous and avalanche led yielding in the case of the unpinned glass, for the case of large pinning concentration, yielding takes place via a spatially homogeneous proliferation of localized events.