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arXiv · 0707.4014

Reversible plasticity in amorphous materials

M. Lundberg·K. Krishan·N. Xu·C. S. O'Hern·M. Dennin
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Abstract

A fundamental assumption in our understanding of material rheology is that when microscopic deformations are reversible, the material responds elastically to external loads. Plasticity, i.e. dissipative and irreversible macroscopic changes in a material, is assumed to be the consequence of irreversible microscopic events. Here we show direct evidence for reversible plastic events at the microscopic scale in both experiments and simulations of two-dimensional foam. In the simulations, we demonstrate a link between reversible plastic rearrangement events and pathways in the potential energy landscape of the system. These findings represent a fundamental change in our understanding of materials--microscopic reversibility does not necessarily imply elasticity.

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M. Lundberg, K. Krishan, N. Xu, C. S. O'Hern, M. Dennin. 2007-09-13. Reversible plasticity in amorphous materials. https://doi.org/10.1103/physreve.77.041505

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