Magnetic effects in particle adhesion. Part III. Magnetite particles on steel and glass

The adhesion phenomena of uniform spherical magnetite particles in an aqueous environment, on steel and glass beads of the same charge sign, have been investigated as a function of the imposed magnetic field. The latter causes a substantial increase in the rate of particle uptake by steel. On glass, the initial deposition rate is low, but it is enhanced once the first layer of magnetite is formed on the beads. With increasing strength of the magnetic field, the repulsion barrier gradually diminishes, allowing particles to be attached directly to the surface. The particles thus deposited are not easily released once the field is eliminated. The energy well is sufficiently broad to permit multilayer formation of adhered particles.