METHOD FOR PRODUCING RARE EARTH SINTERED MAGNETS

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The present invention provides a method for producing a long and large-sized rare earth sintered magnet having a large size in a magnetic field application direction in which a single magnet body in each portion has uniform and high magnetic characteristics. Disclosed is a method for producing a rare earth sintered magnet, including the steps of : 1) preparing a slurry that contains an alloy powder containing a rare earth element, iron, and boron, and a dispersion medium at a predetermined ratio; 2) preparing a cavity that is enclosed with a mold, and an upper punch and a lower punch, at least one of which is movable toward and away from the other one in the mold, and also includes an outlet for discharging the dispersion medium of the slurry; 3) applying a magnetic field of 1.5 T or more in the cavity in the direction parallel to the direction in which at least one of the upper punch and the lower punch is movable, and supplying the slurry at a flow rate of 20 to 600 cm3/second in a state where the upper punch and the lower punch remain stationary, to fill the cavity with the slurry; 4) producing a molded body of the alloy powder by press molding in the magnetic field in which the upper punch and the lower punch come closer to each other while applying the magnetic field; and 5) sintering the molded body.