R a-T a-B based sintered magnet and its manufacturing method

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PROBLEM TO BE SOLVED : To provide an R-T-B-based singer magnet that is able to exhibit high Hat a high temperature without using Dy and Tb and to provide a manufacturing method therefore.SOLUTION : An R-T-B-based sinter magnet contains rare earth elements, such as Nd and PR, Fe, and B, and is formed from an inter-metal compound as a main phase, the inter-metal compound being expressed by a general formula RTB (here, R is one or more types of rare earth element with 50% or more Nd by a mass ratio, and T is Fe or/and Co). In density measurement using spectrometry in a cross-section containing 10 to 100 crystal grains of the inter-metal compound, the R-T-B-based singer magnet has a surface layer part in which the density of Pr is higher than that of the central part of the R-T-B-based sinter magnet. In at least a portion of the surface layer part, the mass proportion of Pr to the rare earth elements contained by a metal phase present at the grain boundary multiple point of the crystal grains is 75% or less, and is 20% higher than the mass proportion of Pr to the rare earth elements contained by the crystal grains adjacent to the metal phase.