Service Communautaire d'Information sur la Recherche et le Développement - CORDIS



Project ID: G1RD-CT-2001-00538
Financé au titre de: FP5-GROWTH
Pays: Poland

New system for testing magnetic properties at high frequencies and under rotating magnetic fields

As planned within the project, we have developed a completely new form of measuring system by which the properties of dielectromagnetic composites can be more accurately and realistically measured. MAG-TD200 computerised measuring system provides a fully automatic process for the complex testing of the magnetic materials properties. It enables testing of magnetic properties in alternating fields at frequency range from 5 to 2000Hz (the range of frequency was extended in relation to previous project assumption 1600Hz), and in rotational fields with any elliptical degree and direction of rotation at frequency range from 20 to 400Hz (the range of frequency was extended in regards to the one in previous project assumption -200Hz). The possibility of measuring magnetic properties of materials under rotational fields makes this system unique on a global scale. The measurements under alternating fields can be taken on ring samples, strips (by means of Epstein frame), single sheet tester and yokes for samples in shape of beams. The measurements under rotational fields can be taken on a cylindrical (for powder composite and electrical sheets) or square specimens (electrical sheets), with winded two coils orthogonal to each other for induction measurement of each measurement channel.

MAG TD200 system enables, among others, measuring of the following characteristics of magnetic materials: magnetization curve (up to magnetic field intensity H=15kA/m or magnetic induction B=2.0T), coercive field intensity Hc, remanence Br, total energy loss with division into hysteresis loss and eddy-current loss, amplitudal relative magnetic permeability. The "peep" of hysteresis loop for the required value of polarization and magnetic field intensity with full description of the parameters is also possible. For interpretation of results, the possibility of checking Fourier series distribution with full description and spectral lines diagram for each measuring point of magnetic field intensity, total energy loss, specific apparent loss (with determination of deformation loss) and polarization in some cases is very useful. The system also has the possibility of controlling the measured object's temperature and conducting measurements in wide temperature range. It is very important, especially during measurements at high frequencies during which temperature of the measured object might be changing, as the result of generating high-energy loss.

In case of rotational fields, all of the above characteristics are measured and determined for two channels - x and y - simultaneously. Moreover, in rotational fields, MAG-TD200 system enables measuring and determination of rotational loss, angle between H and B vectors PhaXY, peak value of field intensity Hm, peak value of polarization Jm, hysteresis loop for required polarization value: Bx=f(Hx), By=f(Hy), By=f(Jx), Hy=f(Hx), By=f(Bx) and Hy=f(Hx) simultaneously. Additionally, the method for measuring total energy loss anisotropy by means a yoke for rotational fields has been elaborated. The obtained results of total energy loss anisotropy, measured by means of the developed method (vector method) and by anisometer are very similar.

Informations connexes


Bogumil WEGLINSKI, (professor)
Tél.: +48-713203476
Fax: +48-713203476