Stress induced magnetic anisotropy and giant magnetoimpedance in Fe-rich glass-coated magnetic microwires

The effect of conventional (CA) and stress annealing (SA) on magnetic properties of ${\mathrm{Fe}}_{74}{\mathrm{B}}_{13}{\mathrm{Si}}_{11}{\mathrm{C}}_2$ glass-coated microwires has been studied. CA treatment does not significantly change the character of the hysteresis loop. Under certain annealing conditions (annealing temperature, $T_{\mathrm{ann}}\text{>300\hspace{0.05em}°}\mathrm{C},$ applied stress, $\text{σ>700\hspace{0.05em}}\mathrm{MPa})$ rectangular hysteresis loop transforms into the inclined with magnetic anisotropy field above 1000 A/m. Such phenomenology has been related to the induction of transverse magnetic anisotropy by SA treatment. Under tensile stress the SA annealed microwire recovers rectangular hysteresis loop. Samples subjected to stress annealing show noticeable magnetoimpedance and stress impedance effects in spite of their large magnetostriction.