Dependence of magnetic susceptibility on stress in textured polycrystalline Fe81.6Ga18.4 and Fe79.1Ga20.9 Galfenol alloys

Magnetization and magnetostriction measurements in constant tension and compression as a function of applied magnetic field are reported for ⟨100⟩ oriented, textured polycrystalline Fe81.6Ga18.4 and Fe79.1Ga20.9 Galfenol alloys. The susceptibility change with stress, or sensitivity, is maximum at zero field for both alloys. The greatest sensitivity is observed for the 18.4 at. % Ga alloy between −10 and +20 MPa, where domain wall motion dominates. The sensitivity is greater for the 20.9 at. % Ga alloy than for the 18.4 at. % Ga alloy below −15 MPa (domain rotation region). The difference in behavior is attributed to a difference in the anisotropy coefficient.