Magnetic bistability of glass-covered Fe-rich amorphous micro wire: Influence of heating treatments and applied tensile stress

The influence of heat treatments and mechanical stresses on the magnetic behaviour of an Fe-rich glass-covered amorphous ferromagnetic microwire (diameter about 20 mm) is reported here. The behaviour is characterized by a magnetization process with a single and large Barkhausen jump at a given applied field. For the as-prepared material, the switching field corresponding to this bistable behaviour is around 100 A m^-1 and can be significantly modified by adequate heating treatments as well as by application of mechanical stresses. These changes are discussed in terms of the modification of the internal stresses.