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arXiv · 1103.1865

Shear-driven solidification of dilute colloidal suspensions

Alessio Zaccone·Daniele Gentili·Hua Wu·Massimo Morbidelli·Emanuela Del Gado
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Abstract

We show that the shear-induced solidification of dilute charge-stabilized (DLVO) colloids is due to the interplay between the shear-induced formation and breakage of large non-Brownian clusters. While their size is limited by breakage, their number density increases with the shearing-time. Upon flow cessation, the dense packing of clusters interconnects into a rigid state by means of grainy bonds, each involving a large number of primary colloidal bonds. The emerging picture of shear-driven solidification in dilute colloidal suspensions combines the gelation of Brownian systems with the jamming of athermal systems.

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Alessio Zaccone, Daniele Gentili, Hua Wu, Massimo Morbidelli, Emanuela Del Gado. 2011-03-09. Shear-driven solidification of dilute colloidal suspensions. https://doi.org/10.1103/physrevlett.106.138301

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