Rheological Properties of Bimodal Magnetic Suspensions

Abstract

The rheological behavior of magnetic suspensions can be maximized by using bidisperse particles having different size (i.e. bimodal suspensions). The size ratio is crucial with regard to stability and MR effect. A rich domain of rheological behavior exists for a wide range of particle diameters covering the magnetic single-multidomain transition spanning the gap between ferrofluids and conventional magnetorheological fluids, the particle interaction parameter varying in a very large interval. In the wide size region from several nanometers to a few micrometers, bimodal MR fluids, among them ferrofluid based ones, are analyzed and discussed to explore and demonstrate the feasibility and advantages of suspensions of different sized particles.