Abstract: An object of the present invention is to provide an R-T-B based permanent magnet showing high residual magnetic flux density Br and coercive force HcJ. Provided is an R-T-B based permanent magnet in which, R is a rare earth element, T is an element other than the rare earth element, B, C, O or N, and B is boron. R at least includes Tb and T at least includes Fe, Cu, Co and Ga, and a total of R content is 28.05 to 30.60 mass %, Cu content is 0.04 to 0.50 mass %, Co content is 0.5 to 3.0 mass %, Ga content is 0.08 to 0.30 mass %, and B content is 0.85 to 0.95 mass %, relative to 100 mass % of a total mass of R, T and B, and Tb concentration reduces from outside to inside of the R-T-B based permanent magnet.

Abstract: An object of the present invention is to provide an R-T-B based permanent magnet showing high residual magnetic flux density Br and coercive force HcJ, and further showing the same also after heavy rare earth element is diffused along grain boundaries. Provided is an R-T-B based permanent magnet in which, R is a rare earth element, T is an element other than the rare earth element, B, C, O or N, and B is boron. T at least includes Fe, Cu, Co and Ga, and a total of R content is 28.0 to 30.2 mass %, Cu content is 0.04 to 0.50 mass %, Co content is 0.5 to 3.0 mass %, Ga content is 0.08 to 0.30 mass %, and B content is 0.85 to 0.95 mass %, relative to 100 mass % of a total mass of R, T and B.

Abstract: An object of the present invention is to provide an R-T-B based permanent magnet showing high residual magnetic flux density Br and coercive force HcJ. Provided is an R-T-B based permanent magnet in which, R is a rare earth element, T is an element other than the rare earth element, B, C, O or N, and B is boron. R at least includes Tb and T at least includes Fe, Cu, Co and Ga, and a total of R content is 28.05 to 30.60 mass %, Cu content is 0.04 to 0.50 mass %, Co content is 0.5 to 3.0 mass %, Ga content is 0.08 to 0.30 mass %, and B content is 0.85 to 0.95 mass %, relative to 100 mass % of a total mass of R, T and B, and Tb concentration reduces from outside to inside of the R-T-B based permanent magnet.

Abstract: An object of the present invention is to provide an R-T-B based permanent magnet showing high residual magnetic flux density Br and coercive force HcJ, and further showing the same also after heavy rare earth element is diffused along grain boundaries. Provided is an R-T-B based permanent magnet in which, R is a rare earth element, T is an element other than the rare earth element, B, C, O or N, and B is boron. T at least includes Fe, Cu, Co and Ga, and a total of R content is 28.0 to 30.2 mass %, Cu content is 0.04 to 0.50 mass %, Co content is 0.5 to 3.0 mass %, Ga content is 0.08 to 0.30 mass %, and B content is 0.85 to 0.95 mass %, relative to 100 mass % of a total mass of R, T and B.

Abstract: The present invention provides an iron nitride based magnetic powder which comprises the Fe16N2 phases and the Fe4N phases. The iron nitride based magnetic powder of the present invention is obtained by subjecting the iron oxide or the starting material to an reduction treatment and a nitriding treatment, wherein the starting material is obtained by covering the surfaces of the iron oxide particles by a Si-based compound as required. The iron nitride based magnetic powder consists of 70 at % or more and 95 at or less of the phases of Fe16N2. compound and 5 at % or more and 30 at % or less of the phases of Fe4N compound in terms of Fe as measured by the Mossbauer spectra.