Magnetoviscous Effect of Hematite Colloid

Abstract

The effect of magnetic field on the viscosity of hematite colloid was investigated. Our experimental results and theoretical considerations revealed that although the hematite parti cles have strong magnetic moments enough to orient along the external magnetic field, the moments are not large enough to cause aggregation in dilute electrolyte aqueous solution. Namely, the magnetoviscous effect of hematite colloid was not caused by the aggregation due to the magnetic interaction. The effect could be accounted for by the hindrance to paricle rotation caused by the magnetic torque.