Magneto-Impedance Effect in Amorphous and Nanocrystalline Glass-Covered Wires

Abstract

We report results on the magneto-impedance effect in Fe_73.5Cu₁Nb₃Si_13.5B₉ nanocrystalline glass-covered wires, Co_68.15Fe_4.35Si_12.5B₁₅ amorphous wires, and in such wires after glass removal. The results are compared with those obtained for cold drawn and then tension annealed Co_68.15Fe_4.35Si_12.5B₁₅ amorphous wires. The magneto-impedance response of nanocrystalline wires after glass removal is larger than that of CoFeSiB amorphous wires after glass removal, being almost equal to that of cold drawn CoFeSiB amorphous wires. The results are explained in terms of specific domain structures and magnetic properties of the discussed wires, and they reveal the importance of good soft magnetic properties in a large magneto-impedance effect.