Force and stiffness behavior of natural rubber based magnetorheological elastomer bushing

This research introduces a magnetorheological elastomer (MRE) bushing that has the potential to be applied to vibration control for automotive applications. An annular shape of MRE bushing is designed and fabricated by natural rubber (NR) based MRE with homogenous distribution of carbonyl iron particles (CIPs). The component consists of five parts, which are the inner and outer pipes, MRE, coil bobbin that wound by an electromagnetic coil, top and bottom ring plates, and housing. Based on a conceptual design, the electromagnetic circuit is simulated using Finite Element Method Magnetics (FEMM) software for analyzing the distribution of magnetic flux. The fabricated MRE bushing is undergone a compression test and load adhesion test for the performance evaluation. The compression test is conducted by using the Universal Testing Machine (UTM) under various applied currents to obtain the force-displacement and stiffness behavior of the device. This study demonstrated that higher forces and stiffness are achieved compared to other MRE bushings. From here, at 5.5 mm of displacement, the ranges of forces are from 7.1 kN (off-state) to 8.5 kN (on-state at 2.5 A). Furthermore, the stiffness is increased by 19% from off-state to 2.5 A. Overall, the fabricated MRE bushing shows a significant response with the presence of the magnetic field from the simulation studies and experimental results. Thus, it has the potential for vibration control due to the ability to control rigidity.