Nonlinear viscoelasticity and two-step yielding in magnetorheology: A colloidal gel approach to understand the effect of particle concentration

作者：Segovia Gutierrez J P; Berli C L A; de Vicente J^*

来源：Journal of Rheology, 2012, 56(6): 1429-1448.

DOI：10.1122/1.4742186

• magnetic field effects
• magnetorheology
• viscoelasticity
• yield stress

The yielding behavior of conventional magnetorheological (MR) fluids is revisited for a wide range of magnetic fields and particle concentrations under a colloidal gel perspective. A two-step yielding behavior is found at intermediate magnetic fields (similar to 10 kA/m) that can be explained as a transition from a strong-link to a weak-link (or transition) regime upon increasing the particle concentration in the MR fluid. This two-step yielding behavior is reminiscent of the classical concepts of static (frictional) and dynamic (Bingham) yield stress. By relating macroscopic elastic properties to a scaling fractal model, we could identify the prevalent gelation regime in MR fluids.

• 出版日期2012-11