公开(公告)号：US20180294082A1

公开(公告)日：2018-10-11

申请号：US15967893

申请日：2018-05-01

申请人： TDK CORPORATION

发明人： Tetsuya HIDAKA ,  Takuma HAYAKAWA ,  Makoto IWASAKI ,  Ayato KAKOKI

IPC分类号： H01F1/057 ,  H01F41/02 ,  C22C38/16 ,  C22C38/14 ,  C22C38/00 ,  C22C38/06 ,  C22C38/04 ,  C22C38/10 ,  H01F1/058

摘要： An R-T-B based sintered magnet includes “R”, “T”, and “B”. “R” represents a rare earth element. “T” represents a metal element other than rare earth elements including at least Fe, Cu, Mn, Al, Co, Ga, and Zr. “B” represents boron or boron and carbon. With respect to 100 mass % of a total mass of the R-T-B based sintered magnet, a content of “R” is 28.0 to 31.5 mass %, a content of Cu is 0.04 to 0.50 mass %, a content of Mn is 0.02 to 0.10 mass %, a content of Al is 0.15 to 0.30 mass %, a content of Co is 0.50 to 3.0 mass %, a content of Ga is 0.08 to 0.30 mass %, a content of Zr is 0.10 to 0.25 mass %, and a content of “B” is 0.85 to 1.0 mass %.

公开(公告)号：US20180277288A1

公开(公告)日：2018-09-27

申请号：US15928378

申请日：2018-03-22

申请人： TDK CORPORATION

发明人： Makoto IWASAKI ,  Tetsuya HIDAKA ,  Eiji KATO ,  Takuma HAYAKAWA ,  Hidetake KITAOKA

IPC分类号： H01F1/057 ,  C22C38/16 ,  C22C38/14 ,  C22C38/10 ,  C22C38/06 ,  C22C38/00 ,  C22C38/04

摘要： Provided is an R-T-B based rare earth magnet. R is one or more rare earth elements, T is one or more transition metal elements essentially including Fe or Fe and Co, and B is boron. B content with respect to a total R-T-B based rare earth magnet is 0.80 mass % or more and 0.98 mass % or less. The R-T-B based rare earth magnet includes an R1T4B4 phase.

公开(公告)号：US20180287441A1

公开(公告)日：2018-10-04

申请号：US15936790

申请日：2018-03-27

申请人： TDK CORPORATION

发明人： Hidetake KITAOKA ,  Makoto IWASAKI ,  Tetsuya HIDAKA ,  Eiji KATO ,  Takuma HAYAKAWA

IPC分类号： H02K1/27 ,  H02K9/19

摘要： Provided is a motor including a permanent magnet, in which the permanent magnet includes a high temperature side permanent magnet part exposed to a high temperature inside the motor, and a low temperature side permanent magnet part exposed to a temperature lower than the high temperature inside the motor, and a coercive force of the high temperature side permanent magnet part is higher than the coercive force of the low temperature side permanent magnet part.

公开(公告)号：US20180025820A1

公开(公告)日：2018-01-25

申请号：US15656284

申请日：2017-07-21

申请人： TDK Corporation

发明人： Ayato KAKOKI ,  Makoto IWASAKI ,  Tetsuya HIDAKA ,  Takuma HAYAKAWA

IPC分类号： H01F1/057 ,  B22F3/16 ,  B22F9/04 ,  C22C30/02 ,  C22C28/00

CPC分类号： H01F1/0577 ,  B22F3/16 ,  B22F9/04 ,  B22F2009/044 ,  B22F2201/11 ,  B22F2202/05 ,  B22F2301/45 ,  B22F2998/10 ,  B22F2999/00 ,  C22C28/00 ,  C22C30/02 ,  C22C38/002 ,  C22C38/005 ,  C22C38/06 ,  C22C38/10 ,  C22C38/14 ,  C22C38/16 ,  C22C2202/02 ,  H01F41/0293 ,  B22F9/023 ,  B22F1/0059 ,  B22F3/087 ,  B22F3/14 ,  B22F2003/248

摘要： An R-T-B based sintered magnet containing a first heavy rare earth element, in which R includes Nd, T includes Co and Fe, the first heavy rare earth element includes Tb or Dy, the R-T-B based sintered magnet has a region in which a concentration of the first heavy rare earth element decreases from the surface toward the inside, a first grain boundary phase which contains the first heavy rare earth element and Nd but does not contain Co is present in one cross section including the region, and an area occupied by the first grain boundary phase in one cross section including the region is 1.8% or less.

公开(公告)号：US20170250014A1

公开(公告)日：2017-08-31

申请号：US15443748

申请日：2017-02-27

申请人： TDK CORPORATION

发明人： Tetsuya HIDAKA ,  Yuki NAGAMINE ,  Yoshinori FUJIKAWA

IPC分类号： H01F1/053 ,  C22C38/00 ,  H01F1/08

CPC分类号： H01F1/0536 ,  C22C38/005 ,  H01F1/0577 ,  H01F1/086

摘要： A rare earth permanent magnet includes a main phase composed of a main phase particle and a grain boundary present among a plurality of the main phase particles. The grain boundary includes a region whose electric resistance is higher than that of the main phase.

公开(公告)号：US20170103836A1

公开(公告)日：2017-04-13

申请号：US15285113

申请日：2016-10-04

申请人： TDK CORPORATION

发明人： Tetsuya HIDAKA ,  Takuma HAYAKAWA ,  Makoto IWASAKI ,  Ayato KAKOKI

IPC分类号： H01F1/057 ,  C22C38/14 ,  H01F1/058 ,  C22C38/06 ,  C22C38/04 ,  C22C38/00 ,  C22C38/16 ,  C22C38/10

CPC分类号： H01F1/0577 ,  C22C38/002 ,  C22C38/005 ,  C22C38/04 ,  C22C38/06 ,  C22C38/10 ,  C22C38/14 ,  C22C38/16 ,  H01F1/058 ,  H01F41/0293

摘要： An R-T-B based sintered magnet includes “R”, “T”, and “B”. “R” represents a rare earth element. “T” represents a metal element other than rare earth elements including at least Fe, Cu, Mn, Al, Co, Ga, and Zr. “B” represents boron or boron and carbon. With respect to 100 mass % of a total mass of the R-T-B based sintered magnet, a content of “R” is 28.0 to 31.5 mass %, a content of Cu is 0.04 to 0.50 mass %, a content of Mn is 0.02 to 0.10 mass %, a content of Al is 0.15 to 0.30 mass %, a content of Co is 0.50 to 3.0 mass %, a content of Ga is 0.08 to 0.30 mass %, a content of Zr is 0.10 to 0.25 mass %, and a content of “B” is 0.85 to 1.0 mass %.

公开(公告)号：US20190074114A1

公开(公告)日：2019-03-07

申请号：US16181811

申请日：2018-11-06

申请人： TDK Corporation

发明人： Makoto IWASAKI ,  Tetsuya HIDAKA ,  Takuma HAYAKAWA ,  Ayato KAKOKI ,  Yoshinori FUJIKAWA ,  Syota GOTO ,  Haruna NAKAJIMA ,  Takeshi MASUDA ,  Chikara ISHIZAKA

IPC分类号： H01F1/055 ,  H01F41/02 ,  H01F1/057

摘要： Provided is a sintered magnet that is an R-T-B based sintered magnet having a region having a concentration of at least one heavy rare earth element decreasing from the surface toward the inside, in which the at least one heavy rare earth element includes at least either of Tb or Dy, R includes Nd, T includes Fe, Co, and Cu, there is a grain boundary phase containing at least either of Tb or Dy and Nd between two main phase particles, and a value obtained by subtracting a half value width of a concentration distribution curve of Cu from a half value width of a concentration distribution curve of Tb or Dy in a part including the grain boundary phase is from 10 to 20 nm.

公开(公告)号：US20180286544A1

公开(公告)日：2018-10-04

申请号：US15936752

申请日：2018-03-27

申请人： TDK CORPORATION

发明人： Takuma HAYAKAWA ,  Makoto IWASAKI ,  Tetsuya HIDAKA ,  Eiji KATO ,  Hidetake KITAOKA

IPC分类号： H01F1/057 ,  H01F41/02

摘要： Provided is an alloy for R-T-B based rare earth magnet. “R” is one or more of a rare earth element, ‘T’ is one or more of a transition metal element essentially including Fe or Fe and Co, and “B” is boron. The alloy includes a single or a plural number of main phase (A), having a minimum length of 10 μm or more and a maximum length of 30 μm or more and 300 μm or less, in a cross section cut along a thickness direction of the alloy. The main phase (A) includes an R2T14B phase, and an area ratio of the main phase (A) to an entire cross section is 2% or more and 60% or less.

公开(公告)号：US20170221616A1

公开(公告)日：2017-08-03

申请号：US15420151

申请日：2017-01-31

申请人： TDK Corporation

发明人： Makoto IWASAKI ,  Tetsuya HIDAKA ,  Takuma HAYAKAWA ,  Ayato KAKOKI ,  Yoshinori FUJIKAWA ,  Syota GOTO ,  Haruna NAKAJIMA ,  Takeshi MASUDA ,  Chikara ISHIZAKA

IPC分类号： H01F1/055 ,  C22C38/14 ,  C22C38/10 ,  B22F3/10 ,  C22C38/00 ,  B22F1/00 ,  B22F9/02 ,  C22C38/16 ,  C22C38/06

CPC分类号： H01F1/0557 ,  B22F1/0059 ,  B22F3/1017 ,  B22F9/026 ,  B22F2009/044 ,  B22F2202/05 ,  B22F2301/35 ,  B22F2998/10 ,  B22F2999/00 ,  C22C33/02 ,  C22C38/002 ,  C22C38/005 ,  C22C38/06 ,  C22C38/10 ,  C22C38/14 ,  C22C38/16 ,  C22C2202/02 ,  H01F1/0577 ,  H01F41/0293 ,  B22F9/023 ,  B22F9/04 ,  B22F3/02 ,  B22F3/10

摘要： Provided is a sintered magnet that is an R-T-B based sintered magnet having a region having a concentration of at least one heavy rare earth element decreasing from the surface toward the inside, in which the at least one heavy rare earth element includes at least either of Tb or Dy, R includes Nd, T includes Fe, Co, and Cu, there is a grain boundary phase containing at least either of Tb or Dy and Nd between two main phase particles, and a value obtained by subtracting a half value width of a concentration distribution curve of Cu from a half value width of a concentration distribution curve of Tb or Dy in a part including the grain boundary phase is from 10 to 20 nm.

公开(公告)号：US20170103835A1

公开(公告)日：2017-04-13

申请号：US15285178

申请日：2016-10-04

申请人： TDK CORPORATION

发明人： Tetsuya HIDAKA ,  Takuma HAYAKAWA ,  Makoto IWASAKI ,  Ayato KAKOKI ,  Naoto TSUKAMOTO ,  Fumitaka BABA

IPC分类号： H01F1/053 ,  C22C28/00

摘要： An R-T-B based sintered magnet includes “R”, “T”, and “B”. “R” represents a rare earth element including at least Tb. “T” represents a metal element except rare earth elements including at least Fe, Cu, Mn, Al, and Co. “B” represents boron or boron and carbon. With respect to 100 mass % of a total mass of the R-T-B based sintered magnet, a content of “R” is 28.0 to 32.0 mass %, a content of Cu is 0.04 to 0.50 mass %, a content of Mn is 0.02 to 0.10 mass %, a content of Al is 0.15 to 0.30 mass %, a content of Co is 0.50 to 3.0 mass %, and a content of “B” is 0.85 to 1.0 mass %. Tb2/Tb1 is 0.40 to less than 1.0, where Tb1 and Tb2 (mass %) denote a content of Tb at a surface portion and at a core portion, respectively.