Effect of hydrogenation-disproportionation-desorption-recombination powder processing on the demagnetization process of Nd-Fe-B sintered magnets analyzed by soft X-ray magnetic circular dichroism microscopy

A. Martin-Cid, T. Kawahara, S. Kobayashi, K. Toyoki, D. Billington, Y. Kotani, H. Kubo, Y. Une, T. Iriyama, M. Sagawa, T. Nakamura

Research output: Contribution to journalArticlepeer-review

Abstract

The demagnetization process of a variety of Nd-Fe-B-based magnets produced using different manufacturing techniques are studied by soft X-ray magnetic circular dichroism microscopy. The four magnets studied include a hot deformed magnet, sintered magnets produced from either a N2 jet-milled or a He jet-milled fine powder, and a magnet produced by hydrogenation-disproportionation-desorption-recombination (HDDR) followed by He jet-milling. The coercivity of the HDDR processed magnet is lower than the magnets produced with N2 jet-milled powder even though the size of the grains is smaller. By following the magnetic domain reversal behavior during the demagnetization process, it was found that, while the magnets produced with N2 jet-milled powder and the hot deformed magnet presents a predominance of the reversed magnetic domain propagation, in the HDDR processed magnet the nucleation of individual grains occurs before the reversed magnetic domains propagate. This behavior is associated with a decreased nucleation field of each grain.

Original languageEnglish
Article number168308
JournalJournal of Magnetism and Magnetic Materials
Volume538
DOIs
Publication statusPublished - 2021 Nov 15

Keywords

  • Coercivity
  • Demagnetization process
  • Hydrogenation disproportionation desorption recombination
  • Nd-Fe-B sintered magnet
  • X-ray magnetic circular dichroism microscopy

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics

Fingerprint

Dive into the research topics of 'Effect of hydrogenation-disproportionation-desorption-recombination powder processing on the demagnetization process of Nd-Fe-B sintered magnets analyzed by soft X-ray magnetic circular dichroism microscopy'. Together they form a unique fingerprint.

Cite this