摘要 |
PROBLEM TO BE SOLVED: To provide a high performance rotary machine by unequally distributing La and/or Co and providing a segment ferrite magnet or ring ferrite magnet having high Br and high Hk/iHc. SOLUTION: A rotary machine is provided with a segment ferrite magnet 8. This segment ferrite magnet has the main element composition expressed with (A1-xRx)O.n[(Fe1-yCoy)2O3] (atomic ratio) (however, A is Sr and/or Ba, R is at least a kind of the rare earth element including Y and surely includes La and x, y and n are numerals satisfying the conditions of 5.0<=n<=6.4, 0.01<=x<=0.4 and 0.005<=y<=0.04) and the substantial magnetoplumbite type crystal structure, and moreover lightly doped region of La or Co exists within the range covering a circle of at least the diameter of 0.2 μm. |