Magnetoelastic behavior of glass-covered amorphous ferromagnetic microwire

Particular aspects concerning the magnetoelastic behavior of an Fe-rich glass-covered amorphous ferromagnetic microwire (diameter about 20 /spl mu/m) are reported in both the as-prepared state and after various heat treatments. The main feature of such behavior is that related with the bistable behavior exhibited by the microwire. The magnetization process takes place by a single and large Barkhausen jump at a given applied field. For the as-prepared material, the value of this switching field (H*/spl ap/112 Am/sup -1/) is about one order of magnitude larger than that reported for Fe-rich amorphous wires with a diameter of about 125 /spl mu/m (H*/spl ap/8 Am/sup -1/). The effect of the thermal treatment as well as the stress dependence of H* for as-obtained and treated microwire are also reported and discussed in terms of the stress distribution within the microwire.