MANUFACTURING METHOD FOR RARE-EARTH MAGNET

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Provided is a manufacturing method for a rare-earth magnet such that a rare-earth magnet having a high degree of orientation can be manufactured by ensuring that a compact to be plastically deformed during hot plastic working receives sufficient plastic deformation with less occurrence of cracks on the side surfaces of the compact. This manufacturing method comprises : a step of manufacturing a compact (S); and a step of preparing a plastic working die, which has a die block (D) with a cavity (Ca) and punches (P) which can slide inside the cavity (Ca), and placing the compact (S) inside the cavity (Ca) and applying hot plastic working thereto to manufacture an oriented magnet (C), the cross-section of the cavity (Ca) being larger than the cross section of the compact (S) orthogonal to the direction in which pressure is applied by the punches (P). When W1 is the length of the short side of the cross-section of the cavity (Ca), and t1 is the length of the side of the cross-section of the compact (S) corresponding to the short side of the cavity (Ca), t1/W1 is in the range of 0.55-0.85. At some point in the hot plastic working process, a portion of the compact (S) becomes constrained by the side surfaces of the cavity (Ca) and is prevented from deforming, while the other portions are unconstrained.