Powder Technology, Vol.338, 190-196, 2018
Application of Ni-Zn ferrite powders with polydisperse spherical particles in magnetorheological fluids
We report the steady-state shear response of polydisperse Ni-Zn ferrite-submicrospheres-based magnetorheological fluids (MRFs). The Ni-Zn ferrite spherical particles were prepared by solvothermal method. MRFs of three different concentrations (10, 20 and 40 wt%) were prepared by dispersing Ni-Zn ferrite submicrospheres in silicone oil. These MRFs were subjected to steady-state shear conditions, at different applied magnetic fields. Dynamic yield strength values corresponding to different applied field strengths showed increase in value with increase in magnetic field strength. Furthermore, the dynamic yield strength scaled up with the concentration of Ni-Zn ferrite spherical particles in the carrier fluid. Comparison of the dynamic yield strengths for the MRFs showed that the values depend strongly on the physical properties of the particles such as the particle size, size-distribution (polydispersity) and the saturation magnetization. (C) 2018 Elsevier B.V. All rights reserved.
Keywords:Ni-Zn ferrite submicrospheres;Size-dispersity;Magnetorheological fluid;Dynamic yield stress;Magnetostatic interaction energy