Magnetostriction of Rapidly Quenched Fe-X (X $=$ Al, Ga) Ribbons as Function of the Quenching Rate

In order to investigate the effect of the quenching rate on the magnetostriction of Fe_82.5Ga_17.5 alloy, a set of ribbons was prepared by varying the wheel velocities from 7.5 up to 25 m/s. Additionally Fe₈₅Al₁₅, Fe₈₁Al₁₉ and Fe₇₅Al₂₅ ribbons were prepared under similar conditions. The microstructure shows generally columnar particles and (100) texture perpendicular to the surface of the ribbons. For Fe-Al ribbons, the lattice constant and magnetostriction (which shows volume magnetostriction effect for the higher Al concentrations) increase and saturation magnetization decreases with Al content. However, the average grains size and the lattice constants of Fe_82.5Ga_17.5 and Fe-Al alloys, show large fluctuations with the wheel velocity. For Fe_82.5Ga_17.5, ribbons the magnetostriction values and its character with applied field depend strongly on the quenching rate. The dependence of the longitudinal magnetostriction with wheel speed exhibits a maximum of about 116 ppm at 15 m/s, which is related to the higher degree of (100) texture.