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

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A sintered R-T-B based magnet composition includes : R : not less than 27 mass % and not more than 37 mass % (R is at least one rare-earth element which always includes at least one of Nd and Pr), B : not less than 0.75 mass % and not more than 0.97 mass %, Ga : not less than 0.1 mass % and not more than 1.0 mass %, Cu : not less than 0 mass % and not more than 1.0 mass %, and T : 61.03 mass % or more (where T is at least one selected from Fe, Co, Al, Mn and Si and always includes Fe, such that the Fe content is 80 mass % or more in the entire T). [T]/[B] is greater than 14.0. An R amount is greater in the surface than in the center, and a Ga amount is greater in the surface than in the center. [T]/[B] in the surface is higher than [T]/[B] in the center.