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The effect of various combinations of conditions, i.e., presence of the Earth's magnetic field during and after deformation on the distribution of stray magnetic field of S355 steel sample, which is locally deformed, was investigated. Some of the stages of the experiment were carried out in zero magnetic field. Compensation of the Earth's magnetic field was obtained by the application of a pair of Helmholtz coils. These coils are able to produce homogeneous field compensating Earth's magnetic field over the full length of the sample. Stray magnetic field measurements were carried out along the longest dimension of the sample using the probe consisting of mutually perpendicular sensors allowing the simultaneous measurement of two magnetic field components, i.e., tangential and normal to a surface of the sample. Research has shown that there is a correlation between the level of plastic deformation of the investigated sample and the distribution of stray magnetic field. It was found that the nature of stray magnetic field of the sample depends on presence of external magnetic field during unloading. An attempt was also made, with the finite-element analysis, to verify experimentally obtained stray magnetic field distribution of undeformed sample. [ABSTRACT FROM AUTHOR]

This paper deals with a new analytical parametric magneto-dynamic model of a thin soft magnetic steel sheet (SMSS). The interdependence of the magnetic field and eddy currents inside such an SMSS is calculated by dividing the sheets into an arbitrary number of slices. Using an adequate number of slices, the magnetic field and eddy currents are described piece-wise uniformly across the SMSS for a given excitation dynamics. Dynamic hysteresis loops for arbitrary excitations can be calculated using the proposed model. The calculated results are validated by the measurements on a non-oriented SMSS. [ABSTRACT FROM AUTHOR]

To describe the vector magnetic hysteresis phenomenon of electrical steel sheets, an improved vector Jiles-Atherton hysteresis model is presented. The proposed model is developed based on Berqvist model. First, the anhysteretic magnetization function is improved by modifying the model parameters according to the excitation direction. By this, the modeling results are accurate under different alternating and nonsaturated rotating excitations. Furthermore, to model the magnetic property under saturated rotating excitations accurately, the proposed model is extended by modifying the model parameters according to the measured data. The proposed model is validated through comparisons between modeling and measured results under different alternating and rotating excitations. [ABSTRACT FROM AUTHOR]

In this paper, stress and fatigue-loaded ferromagnetic steel samples were evaluated using three different remanent flux leakage transducers. Giant magnetoresistive sensors were used as the pickup elements. Each transducer has its own integrated local magnetizing section, which allows us to magnetize the tested material in different directions. The defect detection dependency on angle, at which it occurs to the magnetizing field and sensing element, is minimized by gathering and then integrating the information from transducers. The performance of the transducers was verified using a steel plate (S355J2G3) with electro-discharge machined notches. Further experiments were carried out using fatigue and stress-loaded steel samples. [ABSTRACT FROM AUTHOR]

Focuses on a study which examined the modeling of thin steel shells placed in a static magnetic field. Behavior of the sheet; Information on global formulations; Conclusion.

Presents information on a study which developed a mathematical model for magnetization changes in a steel rod under varying torsion in a constant applied magnetic field. Extension to the law of approach to torsional stress; Changes in the energy balance equation; Details on energy balance formulation for torsional stress.

Measures the conventional magnetic parameters and Barkhausen noise in pressure vessel steel samples. Three stages in neutron dose variations; Deterioration of mechanical properties brought by neutron irradiation.