Magnetic Susceptibility and Saturation Magnetization of some Carbonyl Iron Powders used in Magnetorheological Fluids

Abstract

Some commercial carbonyl iron powders, from BASF AG, were characterized through their magnetic susceptibility and saturation magnetization. The saturation magnetization increases in the order: HQ < OX < CS < CC < CL SM. Although all the powders have 96% minimum of iron content, this result suggests that an investigation at higher magnetic fields, under simultaneous shear is very important. The reversibility and the reproducibility of the MR effect were satisfactory, confirming that carbonyl iron powders are good ferromagnetic materials to prepare magnetorheological fluids.