RFeB-BASED MAGNET AND PROCESS FOR PRODUCING RFeB-BASED MAGNET

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The purpose of the present invention is to provide an RFeB-based sintered magnet which, even when relatively thick, has an even and high coercive force throughout the whole magnet. The RFeB-based sintered magnet comprises a base constituted of a sintered object of an RFeB-based magnet comprising Fe, B, and at least one light rare-earth element RL selected from between Nd and Pr and, diffused into the base through the grain boundaries, at least one heavy rare-earth element RH selected from among Dy, Tb, and Ho, wherein the RFeB-based sintered magnet includes a minimum-thickness portion which has a dimension larger than 3 mm, the value obtained by dividing the amount of the heavy rare-earth element(s) RH contained in the RFeB-based sintered magnet by the volume of the RFeB-based sintered magnet is 25 mg/cm3 or greater, and the difference between the local coercive force at a surface of the minimum-thickness portion and the local coercive force at the center of the minimum-thickness portion is not larger than 15% of the local coercive force at said surface.