Vibration characteristics of smart sandwich beams embedded with magnetorheological elastomer cores

Magnetorheological Elastomer (MRE) material consisting of a natural or synthetic rubber filled with micron sized iron particles is a smart material whose properties can be controlled by external excitation. Due to rubber-like properties, MRE maybe appropriate to apply as a core material in sandwich structures. In this paper, the dynamic characteristics of an MRE core embedded smart sandwich beam are investigated. An analytical model based on Frostig’s high order beam theory is enhanced to include viscoelastic material properties and their frequency dependence. In numerical simulations, sandwich beam-like structures with varying portions of MRE core and different boundary conditions are considered. Based on numerical study, mode shapes are changed at some particular frequencies depending on the strength of magnetic field. The maximum change of the resonant frequency is up to 12% and the first resonant peak decreases by about 8dB due to increased damping in MRE when magnetic field applied. MRE core embedded sandwich beam are shown as being able to achieve adjustable stiffness and damping to design tuneable vibration absorber for applications in ship structures.