The dc B-H curve or hysteresis loop of a magnetic material is necessary even in dynamic field analysis. Conventional methods for measuring magnetic properties require special shape specimens like a plate or a rod of specified dimensions. In this paper, we developed a novel technique for measuring the dc magnetic properties of specimens with various shapes using an electromagnet and a special probe having two Hall elements with very small active area. It is also shown that the magnetic field is not uniform near the specimen, and the magnetic field strength H on the surface of the specimen can be obtained by extrapolation. In addition, the dc excitation due to the earth's magnetic field can be avoided by setting small gaps between the specimen and pole pieces. The magnetic properties of an electrical steel sheet and a cylindrical specimen of a soft magnetic composite can be measured using the proposed technique. It is shown that the measured result using the proposed system is almost the same in comparison to a single sheet tester.
ASJC Scopus subject areas
- Physics and Astronomy(all)