R a-T a-B based sintered magnet

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PROBLEM TO BE SOLVED : To provide an R-T-B-based sintered magnet which is small in the difference between an end portion of the magnet and a center portion thereof in coercive force, and is increased in the coercive force of the whole magnet by distributing RH more deeply inside the magnet.SOLUTION : A method for manufacturing an R-T-B-based sintered magnet comprises : the step of preparing at least one R-T-B-based sintered magnet body; the step of preparing a RH distribution source including a heavy rare earth element RH; the step of loading the R-T-B-based sintered magnet body and the RH distribution source into a process chamber; and the RH diffusion step of distributing the heavy rare earth element RH while supplying RH to the R-T-B-based sintered magnet body from the RH distribution source by heating the R-T-B-based sintered magnet body and the RH distribution source in the process chamber. The R-T-B-based sintered magnet body comprises : 14.2-14.6 atom% of a rare earth element; 800 ppm or less of carbon; and 1500-4000 ppm of oxygen.