Permanent magnet, and motor and power generator using the same

摘要

In one embodiment, a permanent magnet includes a magnet main body and a surface portion provided on a surface of the magnet main body. The magnet main body has a composition expressed by a composition formula 1: R(Fep1Mq1Cur1Co1-p1-q1-r1)z1. The surface portion has a composition expressed by a composition formula 2: R(Fep2Mq2Cur2Co1-p2-q2-r2)z2. In the composition formulas 1 and 2, R is at least one element selected from rare earth elements, M is at least one element selected from Ti, Zr and Hf, p1 and p2 are 0.25 to 0.45, q1 and q2 are 0.01 to 0.05, r1 and r2 are 0.01 to 0.1, z1 is 6 to 9, and z2 satisfies 0.8≦z2/z1≦0.995.

主权项

1. A permanent magnet, comprising:
a magnet main body having a composition expressed by a composition formula 1: R(Fep1Mq1Cur1Co1-p1-q1-r1)z1 where, R is at least one element selected from rare-earth elements,M is at least one element selected from Ti, Zr, and Hf,p1 is a number satisfying 0.25≦p1≦0.45 (atomic ratio),q1 is a number satisfying 0.01≦q1≦0.05 (atomic ratio),r1 is a number satisfying 0.01≦r1≦0.1 (atomic ratio), andz1 is a number satisfying 6≦z1≦9 (atomic ratio); and
a surface portion, provided on a surface of the magnet main body, having a composition expressed by a composition formula 2:
R(Fep2Mq2Cur2Co1-p2-q2-r2)z2 where, R is at least one element selected from rare-earth elements,M is at least one element selected from Ti, Zr, and Hf,p2 is a number satisfying 0.25≦p2≦0.45 (atomic ratio),q2 is a number satisfying 0.01≦q2≦0.05 (atomic ratio),r2 is a number satisfying 0.01≦r2≦0.1 (atomic ratio), andz2 is a number satisfying 0.8≦z2/z1≦0.995 (atomic ratio).