Relationships among structure, memory, and flow in sheared disordered materials

TL;DR

This study links microstructural entropy to energy dissipation in sheared disordered materials, providing a model to predict and tailor their rheological behavior based on particle arrangements.

Contribution

It introduces a novel relation between excess entropy and energy dissipation, enabling microstructure-informed rheology modeling for disordered solids.

Findings

Excess entropy correlates with energy dissipation regardless of particle interactions.

A physically-informed model connects microstructure to bulk rheology.

Experimental and simulation data validate the entropy-dissipation relationship.

Abstract

A fundamental challenge for disordered solids is predicting macroscopic yield from the microscopic arrangements of constituent particles. Yield is accompanied by a sudden and large increase in energy dissipation due to the onset of plastic rearrangements. This suggests that one path to understanding bulk rheology is to map particle configurations to their mode of deformation. Here, we perform laboratory experiments and numerical simulations that are designed to do just that: 2D dense colloidal systems are subjected to oscillatory shear, and particle trajectories and bulk rheology are measured. We quantify particle microstructure using excess entropy. Results reveal a direct relation between excess entropy and energy dissipation, that is insensitive to the nature of interactions among particles. We use this relation to build a physically-informed model that connects rheology to microstructure. Our findings suggest a framework for tailoring the rheological response of disordered materials by tuning microstructural properties.