| abstract |
An obtained by absorbing component E and fluorine atoms from R-Fe-B sintered magnet body to the surface, R a E b T c A d F e O f M g composition containing sintered magnet Around the main phase grains composed of (R, E) 2 T 14 A tetragonal crystals in the sintered magnet, with the concentration of F increasing from the center of the magnet body toward the surface of the magnet body. In the crystal grain boundary portion surrounding the crystal grain boundary, the concentration of E / (R + E) contained in the crystal grain boundary is on average higher than the E / (R + E) concentration in the main phase crystal grain, and at least from the surface of the magnet body in the crystal grain boundary portion. (R, E) oxyfluoride exists in a depth region of 20 μm, and in this region, oxyfluoride particles of 1 μm or more are dispersed at a rate of 2,000 or more per 1 mm 2 , and the oxyfluoride has an area. Eddy current loss that accounts for 1% or more of the fraction, and the electrical resistance of the magnet surface layer is higher than the inside Reduced functionally graded rare earth permanent magnets. According to the present invention, it is possible to provide a functionally functional rare earth permanent magnet with reduced generation of eddy currents in a magnetic circuit. [Selection figure] None |