METHOD FOR PRODUCING R-T-B SYSTEM SINTERED MAGNET

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A sintered R-T-B based magnet work and a Pr—Ga alloy are provided. The sintered magnet work contains R : 27.5 to 35.0 mass % (where R is at least one rare-earth element which always includes Nd), B : 0.80 to 0.99 mass %, Ga : 0 to 0.8 mass %, M : 0 to 2 mass % (where M is at least one of Cu, Al, Nb and Zr), a balance T (where T is at least one transition metal element which always includes Fe, such that 10% or less of Fe is replaceable by Co), and inevitable impurities. [T]/55.85>14[B]/10.8 is satisfied where [T] is the T content (mass %) and [B] is the B content (mass %). At least a portion of the Pr—Ga alloy is allowed to be in contact with at least a portion of the sintered magnet work surface, and a first heat treatment is performed at a temperature which is greater than 600° C. but equal to or less than 950° C. A second heat treatment is performed at a temperature which is lower than the temperature of the first heat treatment but which is not less than 450° C. and not more than 750° C.