Performance of a vibration damper using a new compressible magnetorheological fluid with microspheres

Abstract A novel magnetorheological (MR) fluid was synthesised by incorporating compressible, nonmagnetic polyurethane microspheres and ferromagnetic iron particles into polyalphaolefin oil. This innovative composition reduces sedimentation, enhances compressibility beyond that of conventional MR fluids, and achieves comparable yield stress with a lower concentration of iron particles. The new MR fluid was evaluated in a prototype translational vibration damper under dynamic conditions across a range of excitation frequencies. The damper’s response with the compressible fluid differed significantly from that observed with non-compressible fluids. Upon activation, the MR fluid increased flow resistance and enhanced the damper’s elastic response, posing unique challenges for further optimisation. Experimental results demonstrate the potential of employing such compressible MR fluids in applications requiring controlled material characteristics.