Carbonyl iron suspension with halloysite additive and its magnetorheology

The magnetorheological (MR) characteristics of a micron-sized soft magnetic carbonyl iron-based MR fluid were examined using halloysite nanoclay mineral, as an additive. The flow curves measured from a rotational rheometer revealed non-Newtonian Bingham fluid behavior under an applied magnetic field. The sedimentation of the MR fluid with and without the halloysite additive was also measured using a Turbiscan. It was found that the added rod-like hollow nanotubular-structured halloysite improved the sedimentation problem despite the decrease in MR behavior, as determined from the significant decrease in sedimentation rate.