The Precise Measurements of Coercivity Fields of Nd-Fe Ferro-Magnets in Pulsed High Magnetic Fields up to 20T

Abstract:

The measurements of the coercive force (Hc) of magnets are very difficult to determine as a function of the true effective fields in samples with arbitrary shapes. In this study, we tried to obtain the exact coercive force, M-H curve in high and high pulsed magnetic fields up to 20T by using a double-core pick-up. The values of Hc were found over-estimated more than 20% for the Nd-Fe magnets in comparison with those announced by the company, which coincided well with the numerical simulations by using JMAG. The two samples cut along easy and hard axis showed the same saturation magnetizations, reflected by the isotropic microstructure of the raw material.

• Periodical: Key Engineering Materials (Volume 543)
• Pages: 483-486
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.543.483
• Online since: March 2013
• Authors: Hiroyasu Shimoji, Yasushi Nakahata, Koji Yamada, Jio lian Luo, Takashi Todaka, Edmund B. Borkowski, Masato Enokizono
• Keywords: 20T, Effective Fields, Error Estimation, Exact Coercivity, M-H Curve, Nd-Fe-B Sintered Magnet, Pulsed High Magnetic Fields

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