Synthesis of AN Ionic Liquid-Based Magnetorheological Fluid Dispersing Fe84Nb3V4B9 Nanocrystalline Powders

A new magnetorheological (MR) fluid was synthesized by dispersing Fe₈₄Nb₃V₄B₉ nanocrystalline powders in a nonvolatile ionic liquid (N,N-diethyl-N-methyl-N-(2-methoxyethyl) ammonium tetrafluoroborate), which is stable from 282K to 573K. The structure, morphology, and magnetization of Fe₈₄Nb₃V₄B₉ nanocrystalline powders prepared by mechanical alloying were analyzed by using an X-ray diffractometer (XRD), a vibrating sample magnetometer (VSM), and a scanning electron microscopy (SEM), respectively. The magnetic clusters of the synthesized MR fluid were observed by using a digital microscope, and its MR properties were measured by using a cone-plate type viscometer. The experimental results showed that Fe₈₄Nb₃V₄B₉ nanocrystalline powders with an average grain size of 10-20 nm can be prepared by mechanical alloying. The MR fluid is magnetic-field-responsive, behaves like non-Newtonian fluids, and its magnetorheological properties are influenced by the applied magnetic flux density and the width of magnetic clusters.