METHOD FOR MANUFACTURING R-T-B SINTERED MAGNET

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[Problem] To provide a method for manufacturing an R-T-B sintered magnet in which the thickness can be increased up to the grain boundary between two particles in the magnet, the R-T-B sintered magnet having high coercive force even without the use of rare-earth elements and without a significant adverse effect on the coercive force improvement effect even from surface grinding. [Solution] A method including : a step for preparing an R1-T1-A-X alloy sintered compact (where : R1 is primarily Nd; T1 is primarily Fe; A is at least one of Ga, Ti, Zr, Hf, V, Nb, and Mo; and X is primarily B) primarily characterized in that the molar ratio of Ti/(X-2A) is 13 or greater; a step for preparing an R2-Ga-Cu alloy (where R2 is 65-95 mol% of primarily Pr and/or Nd, and the molar ratio of Cu/(Ga+Cu) is 0.1-0.9); and a step for bringing at least a portion of the R2-Ga-Cu alloy into contact with at least a portion of the surface of the R1-T1-A-X alloy sintered compact, and performing a heat treatment at a temperature of 450-600°C.