MINUTE HIGH-PERFORMANCE RARE EARTH MAGNET FOR MICROMINI PRODUCT AND PROCESS FOR PRODUCING THE SAME

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It is intended to obtain a high-performance rare earth magnet, especially to provide effective means for fabricating a rare earth magnet of tiny volume and a micromotor including the same. In particular, a minute high-performance rare earth magnet for micromini products, formed by machining of magnet block materials, which rare earth magnet exhibits a ratio of surface area/volume of 2 mm-1 or greater, having a volume of 100 mm3 or less and exhibits a magnetic characteristic of 280 kJ/m3 or greater (BH)max through reforming of parts degenerated and damaged by the machining by diffusion and infiltration of a rare earth metal from the magnet surface into the magnet interior to at least a depth corresponding to the radius of crystal grains exposed on the outermost surface of the rare earth magnet. R metal or R-metal-containing alloy having been vaporized or converted to fine particles through physical means in a vacuum vessel is caused to three-dimensionally come by flying onto the magnet surface to thereby form a film, and there is carried out diffusion and infiltration of R metal from the magnet surface into the magnet interior to at least a depth corresponding to the radius of crystal grains exposed on the outermost surface of the magnet.