Wyniki wyszukiwania - BazTech

Ograniczanie wyników

1 Journal of Technical Physics

1 2005

Znaleziono wyników: 1

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: pole magnetyczne zmienne

Sortuj według:

Ogranicz wyniki do:

Influence of alternating circular magnetic field strength on magnetoimpedance of glass-coated micro-wire

Kuźmiński M., Lachowicz H. K., Garcia K. L., Zhukov A., Vazquez M.

Journal of Technical Physics

2005

Vol. 46, no 3

165-173

The presented experiments on giant magnetoimpedance (GMI) effect were carried out using glass-coated amorphous micro-wire specimen of its diameter of 22.4 urn and nominal composition of Co67Fe3.85Ni1.45Mo1.7Si14.5B11.5. The main purpose of these experiments was to demonstrate the influence of the AC-current intensity flowing along this specimen and generating circular alternating magnetic field, on the properties of the GMI-effect. To demonstrate this, the GMI-ratio was measured vs. axial DC-field at various intensities of the AC-current ranging from 0.3 up to 5 mA, the range which corresponds to the intensity of the circular field of around 4.8 - 80 A/m at the surface of the micro-wire. The obtained dependences showed that the maximum of the GMI-ratio occurs at the intermediate intensity of the circular field, around 24 A/m (identified with the threshold field of the micro-wire specimen magnetized in the circumferential direction). This result was confirmed analyzing the dependences of the wire impedance plotted vs. the intensity of AC-current for different selected DC-field as a parameter. The results were interpreted considering the expected domain structure in the wire, in particular, that its surface layer was composed of the stripe domains magnetized circumferentially, alternately in opposite directions ("bamboo structure"). Such a structure is created by the magnetoelastic anisotropy. In order to make this explanation more reliable, the penetration depth of the skin-effect was calculated on the grounds of the classical model. Analysis of the AC-field dependence of the penetration depth additionally confirmed the presented interpretation. The main conclusion which can be drawn from the performed experiments is that, in order to achieve optimum parameters of the GMI from the view-point of application in sensors, AC-current intensity should appropriately be chosen.