Heterogeneities in amorphous systems under shear

TL;DR

This paper reviews the development of theories and numerical studies on deformation mechanisms in amorphous materials under shear, highlighting the role of structural heterogeneities and open questions in the field.

Contribution

It provides a comprehensive review of physical theories and recent numerical findings on shear-induced heterogeneities in amorphous systems, emphasizing unresolved issues.

Findings

Identification of shear-transformations as key deformation mechanisms

Insights into the role of structural disorder and elastic interactions

Highlighting the focus on athermal systems in numerical studies

Abstract

The last decade has seen major progresses in studies of elementary mechanisms of deformation in amorphous materials. Here, we start with a review of physically-based theories of plasticity, going back to the identification of "shear-transformations" as early as the 70's. We show how constructive criticism of the theoretical models permits to formulate questions concerning the role of structural disorder, mechanical noise, and long-ranged elastic interactions. These questions provide the necessary context to understand what has motivated recent numerical studies. We then summarize their results, show why they had to focus on athermal systems, and point out the outstanding questions.