Investigation on Magnetoviscous Effects of Water-Based Magnetic Fluid

Abstract

Magnetic fluid or called ferro-fluid is such kind of magnetic nanomaterials, which is stable of solid-liquid two phase colloidal solution composited by magnetic nanoparticles coated by surfactant and highly disperse in a carrier liquid. The basis of magnetic fluid widely applied mainly is due to their unique magnetic properties and rheological properties, which enable its action as intelligent control materials in the magnetic field so as to achieve the goal of magnetic liquid dynamic seal, magnetic damping vibration and so on. In our recent research, the water-based magnetic fluid was synthesized using a co-precipitation method and its magnetorheological properties were studied. During the process, the magnetorheological properties of stable water-based magnetic fluids were determined by magnetic rheometer. The results show that the shear-thinning behavior of magnetic fluids was observed both in the absence and presence of magnetic field. However, there was a remarkable magnetoviscous effect with magnetic field function and the unexpected variation of shear stress was related to the chain aggregation. Furthermore, the constitutive equation of water-based magnetic fluid at a low magnetic field was discussed.