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公开(公告)号:US20180166192A1
公开(公告)日:2018-06-14
申请号:US15802330
申请日:2017-11-02
发明人: Jae Ryung Lee , Dong Hwan KIM , Koon Seung KONG
CPC分类号: H01F1/0577 , B22F3/10 , B22F3/24 , B22F9/04 , B22F2998/10 , B22F2999/00 , C22C1/0441 , H01F41/0293 , C22C2202/02 , B22F9/023 , B22F2003/242 , B22F2003/248
摘要: Disclosed is a method of producing a rare earth permanent magnet including preparing a NdFeB sintered magnet, coating a surface of the NdFeB sintered magnet with a grain boundary diffusion material including R hydrate or R fluoride, and RaMb or M, to form a grain boundary diffusion coating layer, and diffusing the grain boundary diffusion material into a grain boundary of the NdFeB sintered magnet by heat treatment, wherein M is a metal having a melting point higher than a heat treatment temperature during the diffusion, R is a rare earth element, and a and b each represent atomic percentages which satisfy the following Equations (1) and (2): 0.1
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公开(公告)号:US11527356B2
公开(公告)日:2022-12-13
申请号:US16441251
申请日:2019-06-14
发明人: Koon Seung Kong , Dong Hwan Kim
摘要: A method for producing a heavy rare earth grain-boundary-diffused RE-Fe—B-based rare earth magnet and a heavy rare earth grain-boundary-diffused RE-Fe—B-based rare earth magnet produced thereby is disclosed. More particularly, a method for producing a heavy rare earth grain-boundary-diffused RE-Fe—B-based rare earth sintered magnet having a reduced content of a heavy rare earth element is disclosed, in which a hydrogen compound of a heavy rare earth is mainly used as a diffusion material in the production of the grain-boundary-diffused magnet so that a product having uniform and stable quality can be produced. The coercive force of the magnet can be increased while minimizing the amount of heavy rare earth used in the production of the grain-boundary-diffused magnet, by solving the problem that the heavy rare earth is not uniformly diffused into the magnet, and a heavy rare earth grain-boundary-diffused RE-Fe—B-based rare earth magnet produced thereby.
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公开(公告)号:US11897034B2
公开(公告)日:2024-02-13
申请号:US16975838
申请日:2018-09-13
发明人: Dong Hwan Kim , Koon Seung Kong
CPC分类号: B22F3/16 , B22F3/24 , B22F9/04 , C22C28/00 , H01F1/0571 , H01F41/0266 , B22F2003/248 , B22F2009/044 , B22F2202/05 , B22F2301/45 , C22C2202/02
摘要: There is provided a method for manufacturing a rare earth sintered magnet by many times repetitively finely pulverizing a rare earth alloy on a jet mill by supplying high-pressure nitrogen gas to narrow grain size distribution to make an easy alignment in a magnetic field, and by micronizing crystal grains by using a hydrogenation-disproportionation-desorption-recombination (HDDR) process, to improve the coercivity and thermostability of the rare earth sintered magnet.
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公开(公告)号:US20210319935A1
公开(公告)日:2021-10-14
申请号:US16951729
申请日:2020-11-18
发明人: Do Hoon Kim , Hyung Ju Lee , Jae Hyuk Jang , Young Beom Kim , Dong Hwan Kim , Koon Seung Kong
摘要: Disclosed are a rare-earth permanent magnet having improved magnetic properties and a method of manufacturing the same.
A method of manufacturing a rare-earth permanent magnet may include: preparing a mixed powder including i) a first alloy represented by R1aR2bBcMdFebal and ii) a second alloy represented by R2bBcMdFebal where R1 is one or two or more of La, Ce, and Y; R2 is a rare-earth element except for La, Ce, and Y; and M is a metal element; press-forming and sintering the prepared mixed powder in a magnetic field to prepare a sintered body; and performing a heat treatment based on diffusion temperature conditions of an R1 component and an R2 component contained in the prepared sintered body.-
公开(公告)号:US20190385790A1
公开(公告)日:2019-12-19
申请号:US16441251
申请日:2019-06-14
发明人: Koon Seung KONG , Dong Hwan KIM
摘要: Disclosed is a method for producing a heavy rare earth grain-boundary-diffused RE-Fe—B-based rare earth magnet and a heavy rare earth grain-boundary-diffused RE-Fe—B-based rare earth magnet produced thereby, and more particularly to a method for producing a heavy rare earth grain-boundary-diffused RE-Fe—B-based rare earth sintered magnet having a reduced content of a heavy rare earth element, in which a hydrogen compound of a heavy rare earth is mainly used as a diffusion material in the production of the grain-boundary-diffused magnet, so that a product having uniform and stable quality can be produced, and the coercive force of the magnet can be increased while minimizing the amount of heavy rare earth used in the production of the grain-boundary-diffused magnet, by solving the problem that the heavy rare earth is not uniformly diffused into the magnet, and a heavy rare earth grain-boundary-diffused RE-Fe—B-based rare earth magnet produced thereby.
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公开(公告)号:US20240258027A1
公开(公告)日:2024-08-01
申请号:US18423330
申请日:2024-01-26
发明人: Sang Hyub LEE , Dong Hwan KIM , Koon Seung KONG
CPC分类号: H01F41/0266 , B22F3/24 , B22F2003/248
摘要: The manufacturing method of rare earth sintered magnet comprises manufacturing rare-earth alloy of xwt%RE-ywt%B-zwt%TM-bal.wt%Fe; pulverizing the manufactured alloy to a size of 1.0˜5.0 μm or less; orienting and compressing the pulverized alloy in a magnetic field to be magnetized; sintering the magnetized alloy; cleaning the sintered body; forming a low melting point metal layer on the surface of the cleaned body; coating a slurry mixed with a liquid solvent and a heavy rare-earth metal compound on the surface of the low melting point metal layer formed on the sintered body; loading the sintered body with the low melting point metal layer and the heavy rare-earth metal compound coating layer into a heating furnace; loading the sintered body in which the heavy rare-earth metal has diffused into the grain boundaries of the alloy, into a heating furnace; and performing a final heat treatment after the stress relief heat treatment.
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公开(公告)号:US20240006099A1
公开(公告)日:2024-01-04
申请号:US18140853
申请日:2023-09-22
发明人: Do Hoon KIM , Hyung Ju Lee , Jae Hyuk Jang , Young Beom Kim , Dong Hwan Kim , Koon Seung Kong
CPC分类号: H01F1/0577 , H01F41/0266 , B22F3/10 , B22F3/24 , C22C38/005 , C22C38/002 , B22F9/04 , B22F2009/044 , C22C2202/02 , B22F2301/355
摘要: Disclosed are a rare-earth permanent magnet having improved magnetic properties and a method of manufacturing the same.
A method of manufacturing a rare-earth permanent magnet may include: preparing a mixed powder including i) a first alloy represented by R1aR2bBcMdFebal and ii) a second alloy represented by R2bBcMdFebal where R1 is one or two or more of La, Ce, and Y; R2 is a rare-earth element except for La, Ce, and Y; and M is a metal element; press-forming and sintering the prepared mixed powder in a magnetic field to prepare a sintered body; and performing a heat treatment based on diffusion temperature conditions of an R1 component and an R2 component contained in the prepared sintered body.-
公开(公告)号:US11222738B2
公开(公告)日:2022-01-11
申请号:US16099461
申请日:2016-06-10
发明人: Dong Hwan Kim , Koon Seung Kong
摘要: The present invention provides a method for manufacturing a rare-earth magnet, the method comprising the steps of preparing a rare-earth magnet raw material powder including R, Fe and B as composition components (R is one or more elements selected from the rare earth elements including Y and Sc); packing the raw material powder into a molding die, and compacting and molding the raw material powder while applying a magnetic field, wherein, in the compacting and molding step, compacting is performed biaxially, in the directions of X and Y axes, when the magnetic field is applied in the direction of Z axis.
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公开(公告)号:US20210005380A1
公开(公告)日:2021-01-07
申请号:US16975886
申请日:2018-09-13
发明人: Dong Hwan KIM , Koon Seung KONG
摘要: There is provided a method for manufacturing a rare earth sintered magnet having a stable magnetic performance, by uniformly distributing a heavy rear earth element to the surface of the magnet and the grain boundary inside of the magnet by using a mixture of a heavy rare earth compound or a heavy rare earth metal alloy and a rare earth magnet powder, to lower a decrease rate of the magnetic characteristics based on the temperature of the rare earth sintered magnet.
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公开(公告)号:US20190198209A1
公开(公告)日:2019-06-27
申请号:US16099461
申请日:2016-06-10
发明人: Dong Hwan KIM , Koon Seung KONG
CPC分类号: H01F1/08 , B22F3/087 , B22F2301/355 , H01F1/086 , H01F1/153 , H01F1/22 , H01F41/02 , H01F41/0266
摘要: The present invention provides a method for manufacturing a rare-earth magnet, the method comprising the steps of preparing a rare-earth magnet raw material powder including R, Fe and B as composition components (R is one or more elements selected from the rare earth elements including Y and Sc); packing the raw material powder into a molding die, and compacting and molding the raw material powder while applying a magnetic field, wherein, in the compacting and molding step, compacting is performed biaxially, in the directions of X and Y axes, when the magnetic field is applied in the direction of Z axis.
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