希土類磁石における粒界原子配置と磁性の第一原理電子論

• 合田 義弘

  東京工業大学物質理工学院

書誌事項

タイトル別名

• First-Principles Determination of Intergranular Atomic Arrangements and Magnetic Properties in Rare-Earth Permanent Magnets

抄録

Development of high-performance permanent magnets relies on both the main-phase compound with superior intrinsic magnetic properties and the microstructure effect for the prevention of magnetization reversal. In this article, the microstructure effect is discussed by focusing on the interface between the main phase and an intergranular phase and on the intergranular phase itself. First, surfaces of main-phase grains are considered, where a general trend in the surface termination and its origin are discussed. Next, microstructure interfaces in SmFe₁₂-based magnets are discussed, where magnetic decoupling between SmFe₁₂ grains is found for the SmCu subphase. Finally, general insights into finite-temperature magnetism are discussed with emphasis on the feedback effect from magnetism-dependent phonons on magnetism, which is followed by explanations on atomic arrangements and magnetism of intergranular phases in Nd-Fe-B magnets. Both amorphous and candidate crystalline structures of Nd-Fe alloys are considered. The addition of Cu and Ga to Nd-Fe alloys is demonstrated to be effective in decreasing the Curie temperature of the intergranular phase.

収録刊行物

• 粉体および粉末冶金

  粉体および粉末冶金 69 (Supplement), S109-S117, 2022-01-30

  一般社団法人 粉体粉末冶金協会

キーワード

• first-principles calculations
• electron theory
• ferromagnetism
• permanent magnets
• Curie temperature

詳細情報

• CRID: 1390009454796703104
• NII論文ID: 130008145808
• DOI: 10.2497/jjspm.69.s109
• ISSN: 18809014
• ISSN: 05328799
• Web Site: https://www.jstage.jst.go.jp/article/jjspm/69/Supplement/69_S109/_pdf
• 本文言語コード: ja
• データソース種別:
  • JaLC
  • Crossref
  • CiNii Articles
• 抄録ライセンスフラグ: 使用不可