Extraordinary Magnetostrictive Anisotropy in FeGa-based Ribbons

(Fe,Ga)-based alloys exhibit the largest magnetostriction among rare-earth-free alloys, a property of interest for a wide range of sensor, sonar, and actuator applications. Recent reports have shown that magnetostriction can be enhanced in (Fe,Ga)-based alloys by microalloying with rare earths. In this study, samples of (Fe,Ga)-based alloys were prepared with and without glass formers to produce microcrystalline and nanocrystalline alloys. All samples were prepared by melt spinning of arc melted ingots. Subsequent annealing was conducted to either produce a nanocrystalline microstructure or promote homogeneity (microcrystalline alloys). Magnetostriction measurements in the in-plane and out-of-plane orientations of the ribbon samples varied from 10s of ppm to more than 500 ppm, respectively. This extraordinary magnetostrictive anisotropy and the structure and magnetic properties of these alloys will be presented. (Previously supported by LLNL under Contract DE-AC52-07NA2 and currently supported by NSF under award 2326528)