ThMn₁₂型窒素侵入希土類磁石化合物と永久磁石化研究の最近の進展

抄録

The ThMn₁₂-type hard magnetic compounds composed of rare earth elements (R) and 3d ferromagnetic transition metals such as Fe and their interstitially- modified compounds have been known for many years as possible candidates for development of permanent magnet materials. Being the family of compounds of the lowest rare earth contents among known R-Fe compounds, this class of materials attracts renewed interests especially after the discovery of NdFe₁₂N that showed intrinsic magnetic parameters that surpassed those of Nd₂Fe₁₄B (Y. Hirayama, Y.K. Takahashi, S. Hirosawa and K. Hono, Scripta Materialia 95 (2015) 70). In this paper, recent topics related to this class of materials are overviewed and future perspectives are discussed.