Permanent magnet, and motor and power generator using the same

摘要

In one embodiment, a permanent magnet includes a sintered compact having a composition expressed by a composition formula: R p1 Fe q1 M r1 Cu s1 Co 100-p1-q1-r1-s1 (R is a rare-earth element, M is at least one element selected from Zr, Ti, and Hf, 10 ‰¤ p1 ‰¤ 13.3 at%, 25 ‰¤ q1 ‰¤ 40.0 at%, 0.88 ‰¤ r1 ‰¤ 5.4 at%, and 3.5 ‰¤ s1 ‰¤ 13.5at%). The sintered compact includes crystal grains each composed of a main phase including a Th 2 Zn 17 crystal phase, and a Cu-rich phase having a composition with a high Cu concentration and an average thickness of 0.05 µm or more and 2 µm or less.