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arXiv · 1909.00481

Effect of aging on the non-linear elasticity and memory formation in materials

Daniel Hexner·Nidhi Pashine·Andrea J. Liu·Sidney R. Nagel
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Abstract

Disordered solids often change their elastic response as they slowly age. Using experiments and simulations, we study how aging disordered planar networks under an applied stress affects their nonlinear elastic response. We are able to modify dramatically the elastic properties of our systems in the non-linear regime. Using simulations, we study two models for the microscopic evolution of properties of such a material; the first considers changes in the material strength while the second considers distortions in the microscopic geometry. Both models capture different aspects of the experiments including the encoding of memories of the aging history of the system and the dramatic effects on the material's nonlinear elastic properties. Our results demonstrate how aging can be used to create complex elastic behavior in the nonlinear regime.

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Daniel Hexner, Nidhi Pashine, Andrea J. Liu, Sidney R. Nagel. 2019-09-01. Effect of aging on the non-linear elasticity and memory formation in materials. https://doi.org/10.1103/physrevresearch.2.043231

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