This study presents mechanical energy dissipation with a proof-of-concept prototype magnetostrictive (Fe-Ga alloy, galfenol) based shunt circuit using passive electrical components. Magneto strictive material can harvest electricity out of the structural vibrations based on the Villari effect using permanent magnet and pickup coil configuration. The device in this study consists of a polycrystalline galfenol strip bonded to a brass cantilever beam. Two brass pieces, each containing a permanent magnet, are used to mass load at the end of the beam and to provide a magnetic bias field through the galfenol strip. The voltage induced in an induction coil closely wound around the cantilever beam captures the time rate of change of magnetic flux within the galfenol strip as the beam vibrates. To dissipate the electrical voltage output from the pickup coil and/or to change the phase of eddy current from the magnetic flux density fluctuation, a shunt circuit is attached. The effective mechanical impedance for the magnetostrictive shunt circuit is derived in a model. The effectiveness of a series L-R and L-C shunt circuit is demonstrated theoretically and experimentally. The non-linear model parameters, which include the mechanical-magnetic coupling factors, α and αT, and the permeability of galfenol, β, are extracted from experimental measurement. The shunted magnetostrictive damping model of both resistive and capacitance shunt cases compare well with the experimental results.

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