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We present an overview of the factors affecting soft magnetic properties, fast domain wall propagation and giant magnetoimpedance (GMI) effect in thin amorphous wires. The magnetoelastic anisotropy is one of the most important parameters that determine the magnetic properties of glass-coated microwires and therefore annealing can be very effective for manipulation the magnetic properties of amorphous ferromagnetic glass-coated microwires. Increasing of DW velocity in Fe-rich and Fe-Ni based (low Ni content) microwires is achieved after annealing. After heat treatment of Co-rich microwires we can observe transformation of inclined hysteresis loops to rectangular and coexistence of fast magnetization switching and GMI effect in the same sample. On the other hand stress annealing of Fe- and Co-rich microwires allows achievement of considerable magnetic softening and GMI effect enhancement. [ABSTRACT FROM AUTHOR]

We have studied the effect of annealing conditions on magnetic properties of amorphous CoFeNi-based glass-coated microwires. We show that annealing can be very effective for manipulation the magnetic properties of amorphous ferromagnetic glass-coated microwires. Low coercivity and high giant magnetoimpedance (GMI) effect have been observed in as-prepared Co-rich microwires. After annealing of Co-rich microwires we can observe transformation of inclined hysteresis loops into rectangular and coexistence of fast magnetization switching and GMI effect in the same sample. We demonstrate that the switching field value of microwires can be tailored by annealing in the range from 4 to 200 A/m. [ABSTRACT FROM AUTHOR]

Ribbons of composition Co49Ni21Ga30 have been prepared by melt-spinning method. X-ray diffraction investigation revealed single phase with B2 structure at room temperature. However, analysis of magnetization dependence of temperature suggests phase transition in the range 150-250 K. Resistivity measurements revealed similar transition with shift to higher temperatures in the presence of magnetic field. [ABSTRACT FROM AUTHOR]

We studied the magnetization switching in magnetically bistable amorphous ferromagnetic microwires. We observed quite fast domain wall propagation along the microwires and a correlation between the magnetoelastic anisotropy, distribution of the local nucleation field along the length of microwire and the domain wall dynamics. We observed that both DW velocity and the range of fields, limiting single DW dynamics, can be manipulated by internal or applied stresses and by annealing. We also observed that under certain conditions a controllable domain wall (DW) collision can be realized in different parts of the wire, and that it is possible to manipulate the DW dynamics in a field-driven regime. [ABSTRACT FROM AUTHOR]

In this work we studied influence of time and temperature of stress annealing on magnetic properties of amorphous Co-based and CoFeNi-based microwires. We showed that this type of treatment can be very effective for manipulation of magnetic properties of amorphous ferromagnetic glass-coated microwires. Co-based microwires keep S-shape hysteresis loop after any annealing. Annealing of Co-based microwires at different conditions allows tailoring of the saturation field. CoFeNi-based microwires present either S-shape or rectangular shape of the hysteresis loops depending on the value of the axial stress during the annealing. We demonstrated the possibility to change the switching field of microwires with acquired bistability in the range from 0.5 to 25 A/m. [ABSTRACT FROM AUTHOR]

We studied magnetic properties and GMI effect of Finemet-type FeCuNbSiB microwires. We observed that GMI effect and magnetic softness of microwires produced by the Taylor-Ulitovski technique, can be tailored by either controlling magnetoelastic anisotropy of as-prepared FeCuNbSiB microwires or controlling their structure by heat treatment or changing the fabrication conditions. GMI effect has been observed in as-prepared Fe-rich microwires with nanocrystalline structure. [ABSTRACT FROM AUTHOR]

We studied magnetic properties and GMI effect of Finemet-type FeCuNbSiB microwires. We observed that GMI effect and magnetic softness of microwires produced by the Taylor-Ulitovski technique, can be tailored by either controlling magnetoelastic anisotropy of as-prepared FeCuNbSiB microwires or controlling their structure by heat treatment or changing the fabrication conditions. GMI effect has been observed in as-prepared Fe-rich microwires with nanocrystalline structure. [ABSTRACT FROM AUTHOR]