Effects of longitudinal and torsional stress annealing on the magnetic anisotropy in amorphous ribbon materials

The influence of tensile stress annealing on the magnetic properties of amorphous alloys is reported for ribbons belonging to the pseudo ternary system (FeCoNi)75Si15B10. Ribbons of compositions (Co1-xFex)75Si15B10are susceptible to stress annealing in the whole composition range0 ≤ x ≤ 1. A very large easy ribbon axis anisotromy can be produced in the range0.2 ≤ x ≤ 0.7whereas the largest hard ribbon axis anisotropy is producable in the composition range around x=0.15. Ribbons of compositions [CO1-x(Fe0.5Ni0.5)x]75Si15B10are found susceptible to stress annealing only in the range0 ≤ x ≤ 0.7. In all the compositions the induced easy ribbon axis anisotropies are irreversible whereas the hard ribbon axis anisotropies are recoverable with activation energies ≥ 1.55 eV.