Aging in a Colloidal Glass in Creep Flow: Time-Stress Superposition

TL;DR

This paper investigates the aging behavior of a colloidal glass in creep flow, demonstrating a universal time-stress superposition principle that could apply broadly to soft glassy materials.

Contribution

It introduces the concept of time-stress superposition in aging soft glasses, revealing a universal behavior independent of deformation strength and age.

Findings

Viscoelastic behavior is time-dependent and influenced by deformation.

Universal aging behavior emerges when normalized by the relaxation mode.

Time-stress superposition may be a general phenomenon in soft materials.

Abstract

In this work, we study ageing behavior of aqueous laponite suspension, a model soft glassy material, in creep. We observe that viscoelastic behavior is time dependent and is strongly influenced by the deformation field; the effect is known to arise due to ageing and rejuvenation. We show that irrespective of strength of deformation field (shear stress) and age, when imposed time-scale is normalized with dominating relaxation mode of the system, universal ageing behavior is obtained demonstrating time-stress superposition; the phenomena that may be generic in variety of soft materials.