公开(公告)号：US11236411B2

公开(公告)日：2022-02-01

申请号：US16979170

申请日：2019-03-22

Applicant: JFE STEEL CORPORATION

Inventor： Nao Nasu ,  Takuya Takashita ,  Akio Kobayashi

IPC: C22C33/02 ,  C22C38/12 ,  B22F3/10 ,  C22C38/16 ,  B22F1/00

Abstract: Disclosed is an alloyed steel powder for powder metallurgy from which sintered parts that do not contain expensive Ni, or Cr or Mn susceptible to oxidation, that have excellent compressibility, and that have high strength in an as-sintered state can be obtained. The alloyed steel powder for powder metallurgy has: a chemical composition containing Mo: 0.5 mass % to 2.0 mass % and Cu: 1.0 mass % to 8.0 mass %, with the balance being Fe and inevitable impurities; and a microstructure in which an FCC phase is present at a volume fraction of 0.5% to 10.0%.

公开(公告)号：US20210379657A1

公开(公告)日：2021-12-09

申请号：US17282444

申请日：2019-10-10

Applicant: JFE Steel Corporation

Inventor： Makoto Nakaseko ,  Naomichi Nakamura ,  Akio Kobayashi ,  Takuya Takashita

IPC: B22F9/08 ,  B22F1/00 ,  C22C45/02 ,  C22C33/02 ,  H01F1/153

Abstract: A production method for water-atomized metal powder includes: in a region in which the average temperature of a molten metal stream having an Fe concentration of 76.0 at % or more and less than 82.9 at % is 100° C. or more higher than the melting point, spraying primary cooling water at a convergence angle of 10° to 25°, where the convergence angle is an angle between an impact direction on the molten metal stream from one direction and an impact direction on the molten metal stream from any other direction; and in a region in which 0.0004 seconds or more have passed after an impact of the primary cooling water and the average temperature of metal powder is the melting point or higher and (the melting point+100° C.) or lower, spraying secondary cooling water on the metal powder under conditions of an impact pressure of 10 MPa or more.

公开(公告)号：US12006560B2

公开(公告)日：2024-06-11

申请号：US18174649

申请日：2023-02-27

Applicant: JFE STEEL CORPORATION

Inventor： Naoki Yamamoto ,  Takuya Takashita ,  Makoto Nakaseko ,  Akio Kobayashi ,  Akiri Urata ,  Miho Chiba

IPC: H01F1/22 ,  B22F1/00 ,  B22F1/052 ,  B22F1/07 ,  B22F1/08 ,  B22F9/00 ,  C22C38/02 ,  C22C45/02 ,  H01F1/153 ,  H01F3/08 ,  H01F27/255

CPC classification number: C22C38/02 ,  B22F1/052 ,  B22F1/07 ,  B22F1/08 ,  B22F9/002 ,  C22C45/02 ,  H01F1/15308 ,  H01F1/15333 ,  H01F1/22 ,  H01F3/08 ,  H01F27/255 ,  B22F2998/10 ,  C22C2200/02 ,  C22C2202/02 ,  B22F2998/10 ,  B22F9/002 ,  B22F1/08 ,  B22F1/10 ,  B22F3/02 ,  B22F2003/248

Abstract: Provided is an Fe-based nanocrystalline alloy powder. The Fe-based nanocrystalline alloy powder has a chemical composition, excluding inevitable impurities, represented by a composition formula of FeaSibBcPdCueMf, where the M in the composition formula is at least one element selected from the group consisting of Nb, Mo, Zr, Ta, W, Hf, Ti, V, Cr, Mn, C, Al, S, O, and N, 79 at %≤a≤84.5 at %, 0 at %≤b

公开(公告)号：US20210379658A1

公开(公告)日：2021-12-09

申请号：US17282448

申请日：2019-10-10

Applicant: JFE Steel Corporation

Inventor： Makoto Nakaseko ,  Shigeru Unami ,  Akio Kobayashi ,  Takuya Takashita

IPC: B22F9/08 ,  C22C45/02

Abstract: A production method for water-atomized metal powder includes: in a region in which the average temperature of a molten metal stream is higher than the melting point by 100° C. or more, spraying primary cooling water from a plurality of directions at a convergence angle of 10° to 25°, where the convergence angle is an angle between an impact direction on the molten metal stream of the primary cooling water from one direction and an impact direction on the molten metal stream of the primary cooling water from any other direction; and in a region in which 0.0004 seconds or more have passed after an impact of the primary cooling water and the average temperature of metal powder is the melting point or higher and (the melting point+50° C.) or lower, spraying secondary cooling water on the metal powder under conditions of an impact pressure of 10 MPa or more.

公开(公告)号：US10207328B2

公开(公告)日：2019-02-19

申请号：US15529125

申请日：2015-11-24

Applicant: JFE STEEL CORPORATION

Inventor： Takuya Takashita ,  Akio Kobayashi ,  Naomichi Nakamura ,  Toshio Maetani ,  Akio Sonobe ,  Itsuya Sato

IPC: B22F7/00 ,  B22F1/00 ,  C22C38/12 ,  C22C38/16 ,  C22C33/02

Abstract: An Fe—Mo—Cu—C-based alloy steel powder for powder metallurgy has a chemical composition containing Mo: 0.2 mass % to 1.5 mass %, Cu: 0.5 mass % to 4.0 mass %, and C: 0.1 mass % to 1.0 mass %, with a balance being Fe and incidental impurities, wherein an iron-based powder has a mean particle size of 30 μm to 120 μm, and a Cu powder has a mean particle size of 25 μm or less. Despite the alloy steel powder for powder metallurgy having a chemical composition not containing Ni, a part produced by sintering a press formed part of the powder and further carburizing-quenching-tempering the sintered part has mechanical properties of at least as high tensile strength, toughness, and sintered density as a Ni-added part.

公开(公告)号：US12291765B2

公开(公告)日：2025-05-06

申请号：US17755826

申请日：2020-11-12

Applicant: JFE STEEL CORPORATION

Inventor： Kohsuke Ashizuka ,  Nao Nasu ,  Takuya Takashita ,  Shigeru Unami

IPC: C22C38/22 ,  B22F3/10 ,  C22C38/04 ,  C22C38/16 ,  C22C38/20

Abstract: Provided is an alloyed steel powder for powder metallurgy that has excellent compressibility and enables obtaining a sintered body having improved strength as sintered. An alloyed steel powder for powder metallurgy comprises: Cu: 2.0 mass % or more and 8.0 mass % or less; Mo: more than 0.50 mass % and 2.00 mass % or less; one or both of Mn: 0.1 mass % or more and 1.0 mass % or less and Cr: 0.3 mass % or more and 3.5 mass % or less; and a balance consisting of Fe and inevitable impurities, wherein the alloyed steel powder contains particulate oxide, and a total amount of Mn and Cr in the particulate oxide is 0.15 mass % or less with respect to 100 mass % of the alloyed steel powder, and a number ratio of particulate oxide in contact with Cu of FCC structure to the particulate oxide is 50% or more.

公开(公告)号：US11884996B2

公开(公告)日：2024-01-30

申请号：US17595648

申请日：2020-04-10

Applicant: JFE STEEL CORPORATION

Inventor： Nao Nasu ,  Takuya Takashita ,  Akio Kobayashi

IPC: C22C33/02 ,  B22F1/00 ,  C22C38/00 ,  C22C38/18 ,  B22F1/10 ,  C22C38/12 ,  C22C38/16 ,  B22F3/16 ,  C22C38/04

CPC classification number: C22C33/0257 ,  B22F1/00 ,  B22F1/09 ,  B22F1/10 ,  B22F3/16 ,  C22C38/001 ,  C22C38/04 ,  C22C38/12 ,  C22C38/16 ,  C22C38/18 ,  B22F2301/10 ,  B22F2301/35 ,  B22F2302/40 ,  B22F2304/10 ,  B22F2998/10 ,  B22F1/10 ,  B22F3/02 ,  B22F3/1007 ,  B22F3/1028

Abstract: Provided is an iron-based alloy sintered body having a tensile strength of 800 MPa or more, excellent machinability, a microstructure with an average Vickers hardness of 300 Hv or more and 900 Hv or less and a standard deviation of Vickers hardness of 200 Hv or less, and an average pore circularity of 0.30 or more.

公开(公告)号：US11441212B2

公开(公告)日：2022-09-13

申请号：US16769240

申请日：2018-11-30

Applicant: JFE STEEL CORPORATION

Inventor： Takuya Takashita ,  Akio Kobayashi ,  Naomichi Nakamura

IPC: C22C38/12 ,  C22C38/04 ,  C22C38/16 ,  B22F1/00 ,  C22C33/02 ,  B22F1/05

Abstract: Provided is alloyed steel powder having excellent fluidity, formability, and compressibility without containing Ni, Cr, or Si. The alloyed steel powder includes iron-based alloy containing Mo, in which Mo content is 0.4 mass % to 1.8 mass %, a weight-based median size D50 is 40 μm or more, and among particles contained in the alloyed steel powder, those particles having an equivalent circular diameter of 50 μm to 200 μm have a number average of solidity of 0.70 to 0.86, the solidity being defined as (particle cross-sectional area/envelope-inside area).

公开(公告)号：US11364541B2

公开(公告)日：2022-06-21

申请号：US16768692

申请日：2018-11-30

Applicant: JFE STEEL CORPORATION

Inventor： Takuya Takashita ,  Akio Kobayashi ,  Naomichi Nakamura

IPC: B22F9/00 ,  C22C33/02 ,  C22C38/04 ,  C22C38/12 ,  C22C38/16

Abstract: Disclosed is a partially diffusion-alloyed steel powder having excellent fluidity, formability, and compressibility without containing Ni, Cr, and Si. A partially diffusion-alloyed steel powder having excellent fluidity, formability, and compressibility that includes an iron-based powder and Mo diffusionally adhered to a surface of the iron-based powder, in which Mo content is 0.2 mass % to 2.0 mass %, a weight-based median diameter D50 is 40 μm or more, and among particles contained in the partially diffusion-alloyed steel powder, those particles having an equivalent circular diameter of 50 μm to 200 μm have a number average of solidity of 0.70 to 0.86, the solidity being defined as (particle cross-sectional area/envelope-inside area).

公开(公告)号：US10109406B2

公开(公告)日：2018-10-23

申请号：US14764665

申请日：2014-04-08

Applicant: JFE STEEL CORPORATION

Inventor： Takuya Takashita ,  Naomichi Nakamura

IPC: H01F1/26 ,  C22C38/00 ,  C22C33/02 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/42 ,  H01F3/08 ,  H01F41/02

Abstract: Iron powder for dust cores that is appropriate for manufacturing a dust core with low iron loss is obtained by setting the oxygen content in the powder to be 0.05 mass % or more to 0.20 mass % or less, and in a cross-section of the powder, setting the area ratio of inclusions to the matrix phase to be 0.4% or less.