发明名称 Method for producing R-T-B-based sintered magnets
摘要 A method for producing a sintered R-T-B based magnet includes the steps of: providing a sintered R-T-B based magnet body 1; providing an RH diffusion source including a heavy rare-earth element RH (which is at least one of Dy and Tb) and 30 mass % to 80 mass % of Fe; loading the sintered R-T-B based magnet body 1 and the RH diffusion source 2 into a processing chamber 3 so that the magnet body 1 and the diffusion source 2 are movable relative to each other and are readily brought close to, or in contact with, each other; and performing an RH diffusion process in which the sintered magnet body 1 and the RH diffusion source 2 are heated to a processing temperature of more than 850° C. through 1000° C. while being moved either continuously or discontinuously in the processing chamber.
申请公布号 US9368276(B2) 申请公布日期 2016.06.14
申请号 US201113805466 申请日期 2011.07.12
申请人 HITACHI METALS, LTD. 发明人 Kuniyoshi Futoshi
分类号 H01F41/02;H01F7/02;B22F3/24;C22C27/00;C22C33/02;C22C38/00;H01F1/057;C22C1/02 主分类号 H01F41/02
代理机构 Keating & Bennett, LLP 代理人 Keating & Bennett, LLP
主权项 1. A method for producing a sintered R-T-B based magnet, the method comprising the steps of: providing a sintered R-T-B based magnet body; providing a solid RH diffusion source including a heavy rare-earth element RH (which is at least one of Dy and Tb) and 40 mass % to 60 mass % of Fe, the solid RH diffusion source having a solid physical shape; loading the sintered magnet body and the solid RH diffusion source into a processing chamber so that the magnet body and the solid RH diffusion source are movable relative to each other and are readily brought in contact with each other; and performing an RH diffusion process in which the sintered magnet body and the solid RH diffusion source are heated to a processing temperature of more than 850° C. through 1000° C. while being moved either continuously or discontinuously in the processing chamber, and changing a point of contact between the sintered magnet body and the solid RH diffusion source by rotating the processing chamber; wherein the RH diffusion process is carried out with a stirring aid member introduced into the processing chamber, the stirring aid member being made of zirconia, silicon nitride, silicon carbide, boron nitride or a ceramic that includes any combination of zirconia, silicon nitride, silicon carbide, and boron nitride; and the sintered magnet body, the solid RH diffusion source and the stirring aid member are stirred in the processing chamber during the RH diffusion process.
地址 Tokyo JP