Rheometer for investigating the magnetoviscous effect of magnetic fluids.

G. Spur - E. Uhlmann - R. Patzwald

Technical University Berlin, Institute for machine tools and factory management, Pascalstraße 8-9, 10587 Berlin }

Abstract
The rheological behaviour of magnetic fluids changes under the influence of a magnetic field. A modified commercial rheometer is introduced, which is suitable for investigating the magnetoviscous effect of magnetic fluids. The change of viscosity and flow properties depends on the relation between viscous and magnetic stress the fluids are exposed. If the magnetoviscous effect depends not on the temperature the magnetic fluids viscostiy can be calculated in a simple way. For this case some results are shown where the viscosity is calculated by an equation, which decribes the thermal and magnetoviscous behaviour of a magnetic fluid. Figs 10, Refs 8.