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arXiv · 1705.06912

Mean-field scenario for the athermal creep dynamics of yield-stress fluids

Chen Liu·Kirsten Martens·Jean-Louis Barrat
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Abstract

We develop an elasto-plastic description for the transient dynamics prior to steady flow of athermally yielding materials. Our mean-field model not only reproduces the experimentally observed non-linear time dependence of the shear-rate response to an external shear-stress, but also allows for the determination of the different physical processes involved in the onset of the re-acceleration phase after the initial critical slowing down and a distinct well defined fluidization phase. The evidenced power-law dependence of the fluidization time on the distance of the applied to an age dependent static yield stress is not universal but strongly dependent on initial conditions.

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Chen Liu, Kirsten Martens, Jean-Louis Barrat. 2018-02-04. Mean-field scenario for the athermal creep dynamics of yield-stress fluids. https://doi.org/10.1103/physrevlett.120.028004

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