Short range order of FeCo and FeNi amorphous alloys from stress and/or field induced magnetic anisotropy

Abstract

Stress and/or field induced magnetic anisotropies by current annealing of (Fe 1− x Co x ) 75Si 15B 10 (Fe-rich, x ⩽ 0.5) amorphous alloy ribbons have been studied. The results of magnetic anisotropy induced by magnetic field and tensile stress applied simultaneously to amorphous ribbons show that this anisotropy becomes reinforced and depends on both composition and annealing parameters. This enhancement makes the anisotropy induced by stress + field to be different from the addition to the anisotropies separately induced by either stress or field under the same annealing conditions. Moreover this enhancement seems to be much lower than that obtained in (Fe 1− x Ni x ) 80B 20 (Fe-rich). The compositional dependence of index n between the induced magnetic anisotropic K ind( T ann) and the saturation magnetization M s( T ann) has been also performed. The experimental values obtained of this index n differ from that predicted by the theory of directional ordering or atomic pairs of the magnetic anisotropy. This difference may be attributed to the contribution of the FeNi or FeCo tetrahedral holes of Bernal.