Rheological study of magnetic particle suspensions

Viscometry was used to investigate the microstructural properties of various magnetic particle suspensions. Our study was focused primarily on the shape (acicular versus plate-like effects) of magnetic particles, magnetic particle and/or flee concentration, as well as the effects of shear rate. Mean field theory and the Mooney equation were adopted to estimate a maximum packing concentration of magnetic particles (phi(infinity)) as well as the intrinsic viscosity ([eta]). The values of phi(proportional to) and [eta] for different suspensions were used to interpret the microstructure of magnetic particle suspensions. Further, the Casson equation was employed to investigate the dependence of shear rate on the viscosity.