Shear Vibration Property of Magnetically-Responsive Gels in Magnetically Open Looped System

This paper deals with dynamic shear deformation characteristics of magnetically-responsive (MR) gels under inhomogeneous magnetic fields. Magnetic particles as Fe-Si-Ni type which is generally known as permalloy, were dispersed in silicone gel to prepare the MR composite. An external magnetic field is applied only to one side of the MR gel by using magnetically open-looped circuit, and different excitation frequencies with constant shear strain amplitude is also applied to MR gels with each different thickness. The shear displacement-force relation of MR gel in open-looped circuit were observed, and mechanical properties such as storage and loss moduli were evaluated from experimental data. As a result, it is found that the characteristics change to a large extent depending on the applied magnetic field and the thickness of the MR gel.