RFeB SYSTEM MAGNET AND METHOD FOR PRODUCING RFeB SYSTEM MAGNET

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An RFeB system sintered magnet wherein heavy rare-earth element RH which is at least one kind of rare-earth element selected from Dy, Tb and Ho is diffused into base material through the grain boundaries of base material made of a sintered compact of an RFeB system magnet containing RL, Fe and B, where RL represents a light rare-earth element which is at least one kind of rare-earth element selected from Nd and Pr, wherein : size of the RFeB system sintered magnet at smallest-size portion is greater than 3 mm; the amount of heavy rare-earth element RH contained in RFeB system sintered magnet divided by volume of RFeB system sintered magnet is ≧25 mg/cm3; and the difference between local coercivity at the surface of the smallest-size portion and in the central region of the smallest-size portion is equal to or less than 15% of local coercivity at the surface.