Patent number: 6475302
Abstract: Disclosed is a permanent magnet which comprises an alloy containing a hard magnetic phase having a ThMn12 type tetragonal structure and a nonmagnetic phase. The alloy is represented by a general formula given below:
[R1-a(M1)a][T1-b-c(M2)b(M3)c]dx&agr;
where R is at least one rare earth element (including Y), Ml is at least one element selected from the group consisting of Zr and Hf, T is at least one element selected from the group consisting of Fe, Co and Ni, M2 is at least one element selected from the group consisting of Cu, Bi, Sn, Mg, In and Pb, M3 is at least one element selected from the group consisting of Al, Ga, Ge, Zn, B, P and S, X is at least one element selected from the group consisting of Si, Ti, V, Cr, Mn, Nb, Mo, Ta and W, and the atomic ratios of a, b, c, d and &agr; fall within the ranges of 0≦a≦0.6, 0.01≦b≦0.20, 0≦c≦0.05, 6≦d≦11, and 0.5≦&agr;≦2.0.
Type:
Grant
Filed:
December 28, 2000
Date of Patent:
November 5, 2002
Assignee:
Kabushiki Kaisha Toshiba
Inventors:
Wu Mei, Toshiya Sakamoto, Shinya Sakurada, Takao Sawa, Akihiko Tsutai, Akiko Saito, Masashi Sahashi