Magnetoimpedance response in current annealed amorphous wires

Abstract In this work, the magnetoimpedance (MI) effect in amorphous wires submitted to current annealing treatment in vacuum is presented. The influence of circular anisotropy and stress relaxation induced during the annealing on the impedance dependence on external magnetic field is shown. An increase in the MI ratio for the annealed wires is observed up to a maximum value which is approximately three times higher than the maximum value obtained for the as-cast wire. For high enough times of current annealing treatment a decrease in the MI ratio is observed due to the formation of crystalline phase.