Alloys of iron and non-magnetic gallium (of the form Fe1-xGax), collectively referred to as Galfenol, have been shown to exhibit magnetostrictions in excess of 300 ppm under quasi-static magnetic fields [1]. However, to harness the full potential of this material as an actuator, characterization of Galfenol's magneto-mechanical properties under dynamic operating conditions is required. Broadband frequency domain results include strain per applied magnetic field transfer functions and complex electrical impedance functions. The properties investigated were linear mechanical rod stiffness, magneto-mechanical coupling coefficient, modulus of elasticity, and system structural damping. The samples tested were single-crystal cylindrical Galfenol rods with an atomic percentage of Gallium varying from 18 to 22.5. Some rods were composed of laminated strips of Galfenol to reduce eddy current effects and increase the efficiency of transduction. It was found that lamination did not significantly degrade the stiffness nor increase the structural damping, but did increase the magneto-mechanical coupling coefficient by ~50% over the solid rod for the conditions studied.
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