Rheological properties vs Local Dynamics in model disordered materials at Low Temperature

C. Fusco; T. Albaret; A. Tanguy

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arXiv · 1403.7950

Rheological properties vs Local Dynamics in model disordered materials at Low Temperature

C. Fusco·T. Albaret·A. Tanguy

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Abstract

We study the rheological response at low temperature of a sheared model disordered material as a function of the bond rigidity. We find that the flow curves follow a Herschel-Bulkley law, whatever is the bond rigidity, with an exponent close to 0.5. Interestingly, the apparent viscosity can be related to a single relevant time scale $t_{rel}$, suggesting a strong connection between the local dynamics and the global mechanical behaviour. We propose a model based on the competition between the nucleation and the avalanche-like propagation of spatial strain heterogeneities. This model can explain the Herschel-Bulkley exponent on the basis of the size dependence of the heterogeneities on the shear rate.

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C. Fusco, T. Albaret, A. Tanguy. 2014-03-31. Rheological properties vs Local Dynamics in model disordered materials at Low Temperature. https://arxiv.org/abs/1403.7950

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