Kovacs-like memory effect in strain stiffening collagen networks
Abstract
Materials driven far from equilibrium can encode memories of past deformations through long-lived structural reorganisations. Such memory effects-reflecting parameters such as deformation direction, magnitude, and duration have been widely explored in soft amorphous solids. Here, we report a Kovacs-like memory effect manifested as a non-monotonic stress relaxation in vitro biopolymer networks formed by collagen, an essential component of the mammalian extracellular matrix. Using shear rheology combined with in-situ optical imaging, we find that this memory effect emerges exclusively in the nonlinear strain-stiffening regime, and persists over a much broader range of strain amplitudes than previously reported for other viscoelastic amorphous materials. Furthermore, we uncover a strong correlation between the memory response and the development of negative normal stresses and associated strain fields, highlighting the unique nonequilibrium mechanics underlying memory formation in biopolymer networks.
Keywords
Cite
@article{arxiv.2512.13520,
title = {Kovacs-like memory effect in strain stiffening collagen networks},
author = {Abhishek Ghadai and Sayantan Majumdar},
journal= {arXiv preprint arXiv:2512.13520},
year = {2025}
}