Magneto-inductive element

A novel sensitive magnetic head using a magnetoinductive (MI) effect in zero- or negative-magnetostrictive amorphous wires is described. The MI effect refers to the change of an inductance L for an external magnetic field in a ferromagnetic wire element magnetized with a wire AC current I/sub AC/. A 5-mm-length MI element using a folded almost zero-magnetostrictive amorphous wire having a 120- mu m diameter showed a sensitive rate of change of its inductance of more than 50% for an external low frequency field of about 10 Oe (800 A/m) applied in parallel with the element. The a-wire MI element works for a wire current having frequencies up to 1 MHz.<
>