Silica-coated carbonyl iron microsphere based magnetorheological fluid and its damping force characteristics

Silica-coated soft magnetic carbonyl iron (CI) particles with a reduced density and enhanced anti-corrosion properties compared to pristine CI were synthesized and applied as magneto-responsive particles in a magnetorheological (MR) fluid in this study. The MR fluids containing both pristine CI and silica-coated CI particles were injected into a custom-designed MR damper, and their damping characteristics, such as damping force as a function of time, displacement and velocity, were investigated, since vibration attenuation using mechanical damper systems is one of the main applications of MR fluids. Under the same magnetic field strength applied, the damping characteristics of the two MR fluids were observed to be directly related to their yield stresses. (paper)