R-T-B BASED SINTERED MAGNET

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An R-T-B based sintered magnet including main phase particles having an R2T14B type crystal structure. R is at least one rare earth element essentially including a heavy rare-earth element RH. T is at least one transition metal element essentially including Fe or Fe and Co. B is boron. At least one of the main phase particles includes low RH crystal phases inside the main phase particle. The low RH crystal phases include the R2T14B type crystal structure, wherein an RH concentration in the low RH crystal phases is relatively lower than the RH concentration in the whole main phase particles. The R-T-B based sintered magnet may satisfy rs−rc≥20% when an existence ratio of the main phase particles including the low RH crystal phases in a magnet surface layer part is rs (%) and the same in a magnet central part is rc (%).