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Magnetic measurement accuracy for open samples is analyzed using numerical simulations. The finite element method is used for the complete numerical correction of experimental data which are measured with a vibrating sample magnetometer. The magnetization curves are recalculated taking into account the demagnetizing field, the shape of the open magnetic circuit, and the field probe position. Index Terms--Demagnetizing factor, finite elements method (FEM), magnetic measurements, vibrating sample magnetometer (VSM).

The local correlation between the macroscopic numerical simulations and the microscopic experimental behavior of soft magnetic materials (Fe-Si sheets) is investigated. The 2-D and 3-D magnetic field computation involves finite edge-elements and a nonlinear model of the material. The experimental investigation uses the microscopic magneto-optical imaging for thin samples of magnetic material. Index Terms--Finite-element methods, image processing, magneto-optical Kerr effect, soft magnetic material.

This paper presents a new object-oriented software, which is dedicated for the characterization of magnetic materials, including the hysteresis effect, in academic and research activities. The product allows the development and utilization of an information base containing experimental and numerical data related to the magnetic material behavior. The materials may be modeled with different hysteresis models (Preisach, Jiles-Atherton, etc.), implemented in any programming language, which allow the material advanced characterization in any electromagnetic field problem. Index Terms--Hysteresis, magnetic materials, object-oriented programming, software development.

The paper presents a fast method for computing the quasi-stationary electromagnetic field in devices containing both magnetically nonlinear materials and hysteretic materials. The linear iterative procedure of fixed-point type allows the correct evaluation of the local field and of the losses produced by hysteresis and eddy currents. The tests are performed on a single-sheet device used to determine the magnetic material losses under the a.c. uniform field. Index Terms - Losses, hysteresis, eddy currents

This work presents a new method for analyzing quasi-stationary magnetic field in hysteretic media. The vector model of hysteresis proposed here is locally Lipschitzian and monotonous. These properties assure the convergence of the fixed-point iterative procedure. The problem is set in terms of the modified magnetic vector potential. A 2-D computation example for the impulse magnetization process of a ferromagnetic domain is given.