Effect of the oxidation in the surface magnetic properties of as-quenched and relaxed Finemet alloy

In this work a study of the variation of the surface magnetic properties with oxidation in the Finemet amorphous alloy in the as-quenched state and after relaxation at 400 °C for 30 min is presented. The surface magnetization was obtained by the transverse magneto-optic Kerr effect. The results show that the Kerr intensity is higher in the relaxed samples than in the as-quenched ones with the same cycles of oxidation. In addition the surface saturation magnetization in the relaxed samples is reached at low applied that in the as-quenched ones. These facts indicate that structural relaxation of amorphous ribbon favors improvement of the oxidation resistance.