Variable Air-Gap Hysteresimeter An Alternative Method for the Characterization of Permanent Magnets

Aly F. Flores Filho, Hector R. Anocibar, Roberto P. Homrich


The determination of the main magnetic properties of permanent magnets usually requires sophisticated and expensive measuring systems. This work analyzes and proposes a low-cost system for the characterization of Rare-Earth permanent magnets with linear characteristic that is simple to set up. Its magnetic circuit comprehends the permanent magnet under test, a steel yoke, a variable air-gap; a Hall-effect sensor connected to a Gaussmeter measures the flux density within the variable air-gap. The theoretical basis of the proposed measuring system, a description of its assembly, and the results it produces for a Neodymium-Iron-Boron permanent magnet will be presented.

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