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The local susceptibility profile is here proved to be a reliable source of unique information about the internal domain structure and the local magnetization process. In the present work, the profile is studied for a series of magnetically soft amorphous wires having different magnetostriction constants and exhibiting various domain structures. The presence of closure domain structures near the ends of the wires is confirmed. These domains appear regardless of the value of the magnetostriction constant. They reduce the stray field energy and strongly enhance the local values of susceptibility. Index Terms - Amorphous wires, domain structure, magnetic susceptibility, magnetization process.

A magnetization process of FeCoSiB amorphous wire under the ac circumferential magnetic field with a triangular waveform is investigated. We obtained the locus chart of the magnetization vector under circular magnetic field, [h.sub.[Theta]]. By increasing the time differential component of [h.sub.[Theta]], d[h.sub.[Theta]]/dt, the hysteresis becomes noticeable gradually. It is believed that an eddy current damping is responsible for this phenomenon.

The mechanism of particle capture and retention of strongly magnetic particles in HGMS is investigated both theoretically and experimentally. Good quantitative agreement between the theory and experiments is found.

A magnetic sensor which consists of a compound magnetic wire and search coil has a novel performance to induce the detection voltage independent of changing rate of AC external field frequency in every one cycle. The detection voltage is changed by the previous magnetized state of the compound magnetic wire. This paper reports the effect of a DC bias magnetic field which is applied with an AC magnetic field to make an asymmetric field. To make a compound wire a previous magnetized state, the demagnetized wire is magnetized by various orienting DC field [H.sub.0]. When a symmetric AC field Hex and DC bias field Hb are applied to the wire, the wire is magnetized by an asymmetric magnetic field, which consists of a reset field Hr = Hex + Hb and a set field Hs = Hex - Hb. According to the relationship among the critical field Hp, [H.sub.0] and Hb, Hp is independent of the previous magnetized state of wire at Hb of 25 Oe or larger, and the pulse voltage is always induced at a fixed Hp. This phenomenon is very stable and reproducible.

In this paper we report some results on the dependence of the pulsed voltage output on the applied torsion or tensile stress in [Fe.sub.77.5][Si.sub.77.5][B.sub.15] amorphous wires used as magnetostrictive delay lines. The obtained results show a not monotonic dependence of the response of the delay line on applied torsion. For applied tensile stress the response could be fitted by a linear curve for as-cast wires and by an exponential curve for annealed wires. The good ratio between minimum and maximum magnetostrictive delay line signals and the absence of hysteresis suggest the possibility to use this technique in load cells and torque sensors.

Dependence of magnetization dynamics and magneto-impedance effect in positively magnetostrictive [Fe.sub.77.5][Si.sub.7.5][B.sub.15] amorphous wires on annealing conditions was studied. The observed MI ratio of the annealed samples was as much as 36% and the optimum annealing conditions were suggested. The locus of magnetization vector of the annealed wire indicated that the circumferential magnetization was easily proceeded in the annealed wire. It was also suggested that the effect of oxidation should be considered for the samples annealed in air.

The dependence of the magnetic properties of amorphous wire on the diameter have been investigated. The anisotropy constant, hence the internal stress, of the wire increases with the wire diameter. The size of the pinned reverse domain at the wire end increases with the wire diameter. Domain observation shows that irrespective of the change in the wire diameter, the domain structure basically consists of chevron domain layer sandwiched between the surface maze domain and the inner core domain.

Results on the magnetic behavior and properties of negative and nearly zero magnetostrictive amorphous glass-covered magnetic wires and on their changes determined by glass removal, applied tensile stresses, and annealing are reported. The experimental data allow the explanation of their specific magnetic behavior as emerging from the changes produced in the domain structure by these factors. The similarity in behavior between negative and nearly zero magnetostrictive glass-covered wires is due to the very high values of internal stresses induced during preparation.

Results on the helical magnetic anisotropy in positive magnetostrictive amorphous glass-covered magnetic wires are presented. Measurements of the circumferential magnetization component in [Fe.sub.77.5][Si.sub.7.5][B.sub.15] amorphous glass-covered wires show the existence of a non diagonal anisotropy component that determines an inclination of the easy axis of magnetization in the inner region of as-cast wires. Applied torque leads to an increase of the azimuthal magnetization and contributes to the increase of the easy axis inclination, determining an increase of the switching field at which the axial magnetization reversal occurs in these wires. The torsion sensitivity of wires after glass removal is higher than that of glass-covered wires.

The anisotropy distribution in [Fe.sub.77.5][Si.sub.7.5][B.sub.15] amorphous glass-covered wires and wires after glass removal is investigated by FMR measurements. The peaks of the FMR spectra allow the determination of easy axes and anisotropy fields. The anisotropy distribution changes with glass removal and applied stress. The results are explained by considering the magnetoelastic anisotropy of amorphous wires. Index terms--amorphous glass-covered wires, ferromagnetic resonance, magnetic anisotropy, magnetoelastic interactions.