METHOD FOR PRODUCING RARE EARTH MAGNET AND RARE EARTH MAGNET

    公开(公告)号:EP3379550A1

    公开(公告)日:2018-09-26

    申请号:EP16866270.8

    申请日:2016-11-14

    Abstract: A method for producing a rare-earth magnet includes a provision step of providing a Sm-Fe-based alloy containing a SmFe 9+α phase serving as a main phase by rapidly cooling a molten alloy containing Sm and Fe in an atomic ratio of 1:8.75 to 1:12, a hydrogenation-disproportionation step of subjecting the Sm-Fe-based alloy to hydrogenation-disproportionation treatment to allow part of the SmFe 9+α phase (α = 0.1 to 3.0) to undergo phase decomposition into SmH 2 and Fe, a formation step of pressure-forming the Sm-Fe-based alloy that has been subjected to the hydrogenation-disproportionation treatment to provide a formed article, a desorption-recombination step of subjecting the formed article to desorption-recombination treatment to allow the SmH 2 and the Fe provided by phase decomposition in the hydrogenation-disproportionation treatment to recombine, and a nitriding step of subjecting the formed article that has been subjected to the desorption-recombination treatment to nitriding treatment, in which when the Sm-Fe-based alloy obtained in the provision step is subjected to X-ray diffraction, the integrated intensity ratio of the integrated intensity Int(Fe) of a diffraction peak arising from the α-Fe(110) plane to the integrated intensity Int(SmFe) of a maximum diffraction peak arising from a compound of Sm and Fe is 1/9 or less in a range of 2θ = 30° to 50°.

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