抄録
Magnetorheological fluid is known as one of functional fluids, whose rheological properties can be controlled by the applied magnetic field strength. By using this property, brakes, clutches, dampers and various engineering applications have been studied. However, sedimentation of the magnetic particles of MR fluid will result in unsteady dynamic behaviors of the MR devices. In order to overcome this problem, we propose a new magnetoresponsive material named as the MR compound. The basic properties of MR compound have not been elucidated, which is thought to intermediate between liquid and solid. The purpose of this study is to characterize the magnetic field response properties of the MR compounds and to evaluate the transmissibility characteristics of the vibration isolator incorporating the compound. The effects of the magnetic field strength and the shear rate on the resultant viscosity change of the MR compound were investigated experimentally. Also, magnetic particle sedimentation behaviors in both MR compound and MR fluid were compared by the long-term observation. Additionally, the vibration transmission characteristics of a variable viscous vibration isolator incorporating the MR compound was evaluated. Experimental investigations showed that the proposed vibration isolator is able to suppress the vibration in a wide range of frequency band in comparison to the conventional passive isolators.
