Strain Heterogeneity in Sheared Colloids Revealed by Neutron Scattering

TL;DR

This study uses small-angle neutron scattering to experimentally reveal how colloidal suspensions under shear exhibit increasing heterogeneity, transitioning from affine deformation at low shear rates to plastic rearrangements at high shear rates.

Contribution

First experimental evidence showing strain heterogeneity in sheared colloids using neutron scattering, bridging a gap in non-equilibrium colloidal structure studies.

Findings

Deformation transitions from affine to plastic with increasing shear rate.

Neutron scattering effectively captures heterogeneity evolution.

Shear-induced heterogeneity impacts macroscopic behavior.

Abstract

Recent computational and theoretical studies have shown that the deformation of colloidal suspensions under a steady shear is highly heterogeneous at the particle level and demonstrate a critical influence on the macroscopic deformation behavior. Despite its relevance to a wide variety of industrial applications of colloidal suspensions, scattering studies focusing on addressing the heterogeneity of the non-equilibrium colloidal structure are scarce thus far. Here, we report the first experimental result using small-angle neutron scattering. From the evolution of strain heterogeneity, we conclude that the shear-induced deformation transforms from nearly affine behavior at low shear rates, to plastic rearrangements when the shear rate is high.