R-T-B BASED PERMANENT MAGNET

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PROBLEM TO BE SOLVED : To provide an R-T-B based permanent magnet which allows a high coercive force to be achieved even if the amount of use of a heavy rare earth element is reduced. SOLUTION : An R-T-B based permanent magnet 100 comprises primary phase grains 4 of an R2T14B type compound, where R is a rare earth element, T is Fe or any of iron group elements including Fe and Co as essential elements, and B is boron. The R-T-B based permanent magnet includes at least, C, Ga and M (M is at least one selected from a group consisting of Zr, Ti and Nb) other than R, T and B. In the R-T-B based permanent magnet, the content of B is 0.71 mass% or more and 0.88 mass% or less, the content of C is 0.15 mass% or more and 0.34 mass% or less, the content of Ga is 0.40 or more and 1.40 mass% or less and the content of M is 0.25 mass% or more and 2.50 mass% or less. SELECTED DRAWING : Figure 1 COPYRIGHT : (C)2017, JPO&INPIT