R a-T a-B based sintered magnet

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PROBLEM TO BE SOLVED : To provide a method of manufacturing an R-T-B based sintered magnet capable of showing higher intrinsic coercive force Hat a high temperature.SOLUTION : A method of manufacturing an R-T-B based sintered magnet includes : a process 1) in which a sintered body which includes a rare earth element including Nd and an intermetallic compound including Fe and B and expressed by RTB as a main phase is formed; a process 2) in which a heavy rare earth element including at least one of Dy and Tb and the sintered body are heated to diffuse the heavy rare earth element and the heavy rare earth element is concentrated on an outer shell part of a crystal grain of the intermetallic compound; and a process 3) in which, after that, a supply source including Pr and Al and the sintered body in which the heavy rare earth element is diffused are heated to diffuse Pr and Al in the sintered body, the mass ratio of Pr in the rare earth element of the metallic phase existing in the grain boundary multipoint of the crystal grain is made to be equal to or less than 75% in a surface layer part of the sintered body and increased by 20% point or more than the mass ratio of Pr in the rare earth element of the crystal grain adjacent to the metallic phase, and the mass ratio of Al contained in the sintered body is increased by 0.01-0.05% point.