METHOD FOR PRODUCING R-T-B SYSTEM SINTERED MAGNET

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An R-T-B system sintered magnet material and a Pr-Ga alloy are prepared. The sintered magnet material contains 27.5-35.0 mass% of R (R is composed of at least one rare earth element essentially including Nd), 0.80-0.99 mass% of B, 0-0.8 mass% of Ga, and 0-2 mass% of M (M is composed of at least one of Cu, Al, Nb and Zr), with the balance made up of T (T is at least one transition metal element essentially including Fe, with 10% or less of Fe being optionally substituted by Co) and unavoidable impurities. If [T] is the content (mass%) of T and [B] is the content (mass%) of B, [T]/55.85 > 14[B]/10.8 is satisfied. At least a part of the Pr-Ga alloy is brought into contact with at least a part of the surface of the sintered magnet material, and a first heat treatment is carried out at a temperature of more than 600°C but 950°C or less. A second heat treatment is carried out at a temperature that is lower than the temperature of the first heat treatment and that is from 450°C to 750°C (inclusive).