Microstructures and Mechanical Properties of Dense Particle Gels: Microstructural Characterization

TL;DR

This study investigates how microstructural heterogeneity in dense particle gels influences their mechanical properties, revealing that heterogeneous microstructures with longer straight paths exhibit significantly higher elastic and yield strengths.

Contribution

It introduces the application of the straight path method to colloidal gels, linking microstructural heterogeneity to enhanced mechanical properties.

Findings

Heterogeneous microstructures have up to ten times higher elastic properties.

Longer straight paths correlate with increased strength.

Heterogeneity enhances load-bearing capacity in gels.

Abstract

The macroscopic mechanical properties of densely packed coagulated colloidal particle gels strongly depend on the local arrangement of the powder particles on length scales of a few particle diameters. Heterogeneous microstructures exhibit up to one order of magnitude higher elastic properties and yield strengths than their homogeneous counterparts. The microstructures of these gels are analyzed by the straight path method quantifying quasi-linear particle arrangements of particles. They show similar characteristics than force chains bearing the mechanical load in granular material. Applying this concept to gels revealed that heterogeneous colloidal microstructures show a significantly higher straight paths density and exhibit longer straight paths than their homogeneous counterparts.