Permanent magnet, motor, and generator

摘要

A permanent magnet includes: a composition expressed by a composition formula: RpFeqMrCutCo100-p-q-r-t (R is at least one element selected from rare-earth elements, M is at least one element selected from Zr, Ti, and Hf, 10.5≦p≦12.5 at %, 23≦q≦40 at %, 0.88≦r≦4.5 at %, 4.5≦t≦10.7 at %); and a metal structure containing a Th2Zn17 crystal phase and a Cu-rich phase having a Cu concentration higher than that of the Th2Zn17 crystal phase. In a cross section including a c-axis of the Th2Zn17 crystal phase, a number of intersections of the Cu-rich phases existing in an area of 1 μm square is 10 or more.

主权项

1. A permanent magnet comprising:
a composition expressed by a composition formula:
RpFeqMrCutCo100-p-q-r-t where, R is at least one element selected from the group consisting of rare-earth elements, M is at least one element selected from the group consisting of Zr, Ti, and Hf, p is a number satisfying 10.5≦p≦12.5 at %, q is a number satisfying 23≦q≦40 at %, r is a number satisfying 0.88≦r≦4.5 at %, and t is a number satisfying 4.5≦t≦10.7 at %; and a metal structure containing a Th2Zn17 crystal phase and a Cu-rich phase having a Cu concentration higher than that of the Th2Zn17 crystal phase, wherein a number of intersections of the Cu-rich phases existing in an area of 1 μm square in a cross section including a c-axis of the Th2Zn17 crystal phase is 10 or more.