R a-T a-B based sintered magnet

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Provided is a method for manufacturing an R-T-B based sintered magnet that contains 28.5-33.0 mass% of R (R represents at least one type of rare-earth element, and includes Nd and/or Pr), 0.850-0.910 mass% of B, 0.2-0.7 mass% of Ga, 0.05-0.50 mass% of Cu, and 0.05-0.50 mass% of Al with the remainder being T (T represents Fe and Co, and at least 90 mass% of T is accounted for by Fe) and unavoidable impurities, and that satisfies formula (1) (14[B]/10.8<[T]/55.85, where [B] represents the contained amount of B in mass%, and [T] represents the contained amount of T in mass%), the method comprising : a step for preparing an alloy powder in which the particle size D50 and the particle size D99 satisfy formula (2) (3.8 μm ≤ D50 ≤ 5.5 μm) and formula (3) (D99 ≤ 10 μm), respectively; a forming step for obtaining a compact by compressing the alloy powder; a sintering step for obtaining a sintered body by sintering the compact; and a heat treatment step for applying heat treatment to the sintered body.