No. 1357
	Present Status of Researches on Ultra-High-Performance Permanent Magnets and Their Applications
	Investigating R&D Committee on ultra-high-performance permanent magnets and thier applications
	Keyword : Nd-Fe-B magnets, EV and HV motor parts, Dy resource problem, Measurement method, Application of magnets
	Permanent magnet applications are rapidly and widely increased by the applications to EV and HV motor parts. For the applications, Dy substitution for Nd is necessary for obtaining the sufficient coercivity. The beginning 2 chapters in this report relate to the Dy resource problem and saving Dy materials (Chaps. 2, 3). Thin- and thick-film magnets (Chap.4), electric vehicle applications including for the cold climate (Chaps 5, 6) were also reported. Concerning to magnet materials, new developments in Sm2Co17 type magnets (Chap.7), relation between microstructure and coercivity in Ne-Fe-B magnets (Chap.8), and rare-earth-iron-boron rapid cooled thin film magnets (Chap.10) were discussed. As other subjects, aging variations of properties of Fe-Co recording tapes (Chap.11) and developments in magneto-force microscopy (MFM) observations of domain structure were also discussed.
	©2007. The Institute of Electrical Engineers of Japan