中科微点-全球专利检索

  1. Login
  2. Sign Up

Search Results

21 records (took 0.014 seconds)

    FERRITE SINTERED MAGNET AND ROTATING ELECTRIC MACHINE
    2.
    发明申请
    FERRITE SINTERED MAGNET AND ROTATING ELECTRIC MACHINE 有权

    公开(公告)号：US20210304935A1

    公开(公告)日：2021-09-30

    申请号：US17201809

    申请日：2021-03-15

    Applicant: TDK CORPORATION

    Inventor： Shogo MUROYA ,  Yoshitaka MURAKAWA ,  Hiroyuki MORITA ,  Masanori IKEDA

    IPC: H01F1/34 ,  H02K1/02 ,  C01G51/00

    Abstract: To provide a ferrite sintered magnet having a high residual magnetic flux density (Br), a high coercive force (HcJ), a good production stability, and also able to produce at a low cost. The ferrite sintered magnet includes a hexagonal M-type ferrite including A, R, Fe, and Co in an atomic ratio of A1-xRx(Fe12-yCoy)zO19. A is at least one selected from Sr, Ba, and Pb. R is La only or La and at least one selected from rare earth elements. 0.14≤x≤0.22, 11.60≤(12-y)z≤11.99, and 0.13≤yz≤0.17 are satisfied. 0.30≤Mc≤0.63 is satisfied in which Mc is CaO content (mass %) converted from a content of Ca included in the ferrite sintered magnet.

    FERRITE SINTERED MAGNET AND MANUFACTURING METHOD THEREFOR
    5.
    发明公开
    FERRITE SINTERED MAGNET AND MANUFACTURING METHOD THEREFOR 审中-公开

    公开(公告)号：US20240177896A1

    公开(公告)日：2024-05-30

    申请号：US18283739

    申请日：2022-03-24

    Applicant: TDK CORPORATION

    Inventor： Shogo MUROYA ,  Yoshitaka MURAKAWA ,  Hiroyuki MORITA ,  Masanori IKEDA ,  Takuma ABE

    IPC: H01F1/03 ,  H01F1/11

    CPC classification number: H01F1/0315 ,  H01F1/11

    Abstract: A ferrite sintered magnet represented by A1−xRx(Fe12−yCoy)zO19 in terms of atomic number ratio. A is at least one selected from a group made of Sr, Ba and Pb. R is La only or La and at least one selected from a group made of Bi and rare earth elements. 0.14≤x≤0.22, 11.60≤(12−y)×z≤11.99, and 0.13≤y×z≤0.17 are satisfied. 0.500≤Mc≤0.710 is satisfied in which Mc is CaO content in mass % converted from a content of Ca included in the ferrite sintered magnet. 0.410≤Ms≤0.485 is satisfied in which Ms is SiO2 content in mass % converted from a content of Si included in the ferrite sintered magnet.

    FERRITE SINTERED MAGNET
    6.
    发明申请
    FERRITE SINTERED MAGNET 有权

    公开(公告)号：US20210090768A1

    公开(公告)日：2021-03-25

    申请号：US17026848

    申请日：2020-09-21

    Applicant: TDK Corporation

    Inventor： Tomokazu ISHIKURA ,  Masanori IKEDA ,  Yoshitaka MURAKAWA ,  Hiroyuki MORITA ,  Shogo MUROYA

    IPC: H01F1/11 ,  C04B35/26

    Abstract: The present invention provides a ferrite sintered magnet comprising ferrite crystal grains having a hexagonal structure, wherein the ferrite sintered magnet comprises metallic elements at an atomic ratio represented by formula (1). In formula (1), R is at least one element selected from the group consisting of Bi and rare-earth elements, and R comprises at least La. In formula (1), w, x, z and m satisfy formulae (2) to (5). The above-mentioned ferrite sintered magnet further has a coefficient of variation of a size of the crystal grains in a section parallel to a c axis of less than 45%. Ca1-w-xRwSrxFezCom  (1) 0.360≤w=0.420  (2) 0.110≤x≤0.173  (3) 8.51≤z≤9.71  (4) 0.208≤m≤0.269  (5)

    FERRITE SINTERED MAGNET AND ROTARY ELECTRICAL MACHINE COMPRISING THE SAME
    7.
    发明申请
    FERRITE SINTERED MAGNET AND ROTARY ELECTRICAL MACHINE COMPRISING THE SAME 审中-公开

    公开(公告)号：US20200312494A1

    公开(公告)日：2020-10-01

    申请号：US16825356

    申请日：2020-03-20

    Applicant: TDK Corporation

    Inventor： Yoshitaka MURAKAWA ,  Shogo MUROYA ,  Hiroyuki MORITA ,  Masanori IKEDA

    IPC: H01F1/11 ,  H02K1/02 ,  C04B35/26

    Abstract: A ferrite sintered magnet 100 comprises M-type ferrite crystal grains 4 having a hexagonal crystal structure, two-crystal grain boundaries 6a formed between two of the M-type ferrite crystal grains 4, and multiple-crystal grain boundaries 6b surrounded by three or more of the M-type ferrite crystal grains 4. This ferrite sintered magnet 100 contains at least Fe, Ca, B, and Si, and contains B in an amount of 0.005 to 0.9 mass % in terms of B2O3, the two-crystal grain boundaries 6a and the multiple-crystal grain boundaries 6b contain Si and Ca, and in a cross-section parallel to a c-axis of the ferrite sintered magnet, when the number of multiple-crystal grain boundaries having a maximum length of 0.088 or more and less than 0.49 μm per cross-sectional area of 76 μm2 is P, P is 8 or more.

    FERRITE SINTERED MAGNET
    8.
    发明申请
    FERRITE SINTERED MAGNET 审中-公开

    公开(公告)号：US20200255339A1

    公开(公告)日：2020-08-13

    申请号：US16782343

    申请日：2020-02-05

    Applicant: TDK Corporation

    Inventor： Masanori IKEDA ,  Hiroyuki MORITA ,  Yoshitaka MURAKAWA ,  Shogo MUROYA

    IPC: C04B35/26 ,  H01F1/11 ,  H01F41/02 ,  C01G51/00

    Abstract: This ferrite sintered magnet comprises metallic elements at an atomic ratio represented by formula (1): Ca1-w-xRwSrxFezCom   (1) in formula (1), R is at least one element selected from the group consisting of rare-earth elements and Bi, and R comprises at least La, in formula (1), w, x, z and m satisfy formulae (2) to (5): 0.360≤w≤0.420   (2) 0.110≤x≤0.173   (3) 8.51≤z≤9.71   (4) 0.208≤m≤0.269   (5), and in a section parallel to an axis of easy magnetization, when the number of total ferrite grains is N and the number of ferrite grains having a stacking fault is n, 0≤n/N≤0.20 is satisfied.

    FERRITE SINTERED MAGNET
    9.
    发明申请
    FERRITE SINTERED MAGNET 审中-公开

    公开(公告)号：US20200251262A1

    公开(公告)日：2020-08-06

    申请号：US16777940

    申请日：2020-01-31

    Applicant: TDK Corporation

    Inventor： Hiroyuki MORITA ,  Masanori IKEDA ,  Yoshitaka MURAKAWA ,  Shogo MUROYA

    IPC: H01F1/10 ,  C04B35/26 ,  H01F1/03

    Abstract: A ferrite sintered magnet comprises a plurality of main phase grains containing a ferrite having a hexagonal structure, wherein at least some of the main phase grains are core-shell structure grains each having a core and a shell covering the core; and wherein the minimum value of the content of La in the core is [La]c atom %; the minimum value of the content of Co in the core is [Co]c atom %; the maximum value of the content of La in the shell is [La]s atom %; the maximum value of the content of Co in the shell is [Co]s atom %; [La]c+[Co]c is 3.08 atom % or more and 4.44 atom % or less; and [La]s+[Co]s is 7.60 atom % or more and 9.89 atom % or less.

Patent Agency Ranking