Overshoots in stress-strain curves: Colloid experiments and schematic mode coupling theory
نویسندگان
چکیده
Synopsis The stress vs strain curves in dense colloidal dispersions under start up shear flow are investigated combining experiments on model core shell microgels, computer simulations of hard disk mixtures, and mode coupling theory. In dense fluid and glassy states, the transient stresses exhibit first a linear increase with the accumulated strain, then a maximum (stress overshoot) for strain values around 5%, before finally approaching the stationary value, which makes up the flow curve. These phenomena arise in well equilibrated systems and for homogeneous flows, indicating that they are generic phenomena of the shear driven transient structural relaxation. Microscopic mode
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