The Static Characteristic Loop and the External Demagnetizing Factor

J. Takacs, Gy. Kovacs, L. K. Varga

Department of Engineering Science, University of Oxford, Oxford UK.
Department of Materials, Physics of Eotvos Lorant Univ. 1518, Budapest, P.O. Box, 32., Hungary.
Research Institute for Solid State Physics and Optics, 1525, Budapest, P.O. Box 49. Hungary.

DOI: 10.4236/msa.2012.310100                

Abstract

In this paper we demonstrate, that shearing is changing only one parameter of the static loop. By using the shearing factor N_s, linked to the widely used, demagnetization coefficient N_D, we show the one parameter link between the static unsheared and that of the sheared saturation loop, obtained by a non-toroidal, open circuit hysteresis measurement. The paper illustrates the simple relation between open circuit loop data and measured real static saturation data. The proposed theory is illustrated by using the hyperbolic model. For experimental illustration, tests results are used, which were carried out on two closed and open toroidal samples, made of NO Fe-Si electrical steel sheet, mimicking the demagnetization effect of the open circuit VSM measurement. These are both theoretical and experimental demonstrations, that shearing only changes the inclination of the static hysteresis loop. These test results, presented here, agree very well with the calculated results, based on the proposed method.

Keywords

Magnetism; Hysteresis; Modelling; Shearing

Conflicts of Interest

The authors declare no conflicts of interest.

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