Synthesis and magnetorheology of suspensions of submicronsized cobalt particles with tunable particle size

Modesto Lopez-Lopez (1) , Pavel Kuzhir (1) , Alain Meunier (1) , Georges Bossis (1)

1 LPMC - Laboratoire de Physique de la Matière Condensée

Different samples of cobalt powder were synthesized. Particle size and shape were characterized by electron microscopy and light scattering. These measurements showed that the synthesized powders consisted of monodisperse spheres with average diameters ranging between 63 and 760 nm. These powders were used for the preparation of magnetorheological (MR) fluids by dispersing them in silicone oil. The MR properties of these MR fluids were investigated. It was found that particle size did not have much influence on the MR response of MR fluids, for average particle diameters larger than 100 nm. On the other hand, the MR response decreased appreciably when average particle diameter was diminished below 100 nm; a theory based on the change of the aggregates'shape with the size of the particles could explain these observations

Domaines: Mécanique des fluides [physics.class-ph]; Mécanique des fluides [physics.class-ph]

Modesto Lopez-Lopez, Pavel Kuzhir, Alain Meunier, Georges Bossis. Synthesis and magnetorheology of suspensions of submicronsized cobalt particles with tunable particle size. Journal of Physics: Condensed Matter, 2010, 22, pp.324106. ⟨hal-00558932⟩