R-T-B BASED SINTERED MAGNET

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An R-T-B based sintered magnet having a high residual magnetic flux density and a high coercive force in combination is provided. An R-T-B based sintered magnet, which includes a main phase crystal grain (1) having a core-shell structure comprising an inner shell part (2) and an outer shell part (3) surrounding the inner shell part (2). The concentration of a heavy rare earth element in the inner shell part (2) is lower by 10 % or more than the concentration of a heavy rare earth element around the perimeter of the outer shell part (3), and the main phase crystal grain (1) having a core-shell structure comprising the inner shell part (2) and the outer shell part (3) has a (L/r)ave in the range of 0.03 to 0.40, wherein L : a minimum distance from the perimeter of the main phase crystal grain (1) to the inner shell part (2), r : a diameter of the circle equivalent to the main phase crystal grain (1), and (L/r)ave : an average value of L/r of the main phase crystal grain (1) having a core-shell structure being present in the above sintered article.