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Aggregates relaxation in a jamming colloidal suspension after shear cessation

F. Ianni·D. Lasne·R. Sarcia·P. Hebraud
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Abstract

The reversible aggregates formation in a shear thickening, concentrated colloidal suspension is investigated through speckle visibility spectroscopy, a dynamic light scattering technique recently introduced [P.K. Dixon and D.J. Durian, Phys. Rev. Lett. 90, 184302 (2003)]. Formation of particles aggregates is observed in the jamming regime, and their relaxation after shear cessation is monitored as a function of the applied shear stress. The aggregates relaxation time increases when a larger stress is applied. Several phenomena have been proposed to interpret this behavior: an increase of the aggregates size and volume fraction, or a closer packing of the particles in the aggregates.

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F. Ianni, D. Lasne, R. Sarcia, P. Hebraud. 2005-12-13. Aggregates relaxation in a jamming colloidal suspension after shear cessation. https://doi.org/10.1103/physreve.74.011401

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