Measurement of high magnetomechanical coupling factors by resonance techniques

Abstract

Accurate calculations of the very high magnetomechanical couplings of amorphous magnetic ribbons, as measured by resonance techniques, rest precariously on assumptions of the magnetic boundary conditions in the sample. The limiting cases of uniform magnetic field and uniform induction give very different results when the magnetoelastic coupling factor approaches unity. A data analysis scheme presented here allows interpolation between these two extremes by examination of the location of the first resonance harmonic. Data from 4-in. samples of Metglasa 2605SC, annealed in a transverse field, show very clear harmonic resonances allowing a more precise determination of the coupling constant in these materials than reported previously.