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：US11654487B2

公开(公告)日：2023-05-23

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 ,  C22C33/02 ,  C22C45/02 ,  H01F1/153 ,  B22F1/05

CPC classification number: B22F9/082 ,  B22F1/05 ,  C22C33/0278 ,  C22C45/02 ,  H01F1/153 ,  B22F2009/0828 ,  B22F2301/35 ,  B22F2304/10 ,  C22C2200/02 ,  C22C2202/02

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：US11600414B2

公开(公告)日：2023-03-07

申请号：US17262204

申请日：2019-07-25

Applicant: JFE STEEL CORPORATION

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

IPC: H01F1/22 ,  C22C45/02 ,  H01F1/153 ,  B22F9/24 ,  B22F9/00 ,  H01F3/08 ,  H01F27/255 ,  B22F1/07

Abstract: Provided is a soft magnetic powder that can produce a dust core having excellent magnetic properties. The soft magnetic powder has a chemical composition, excluding inevitable impurities, represented by a composition formula of FeaSibBcPdCueMf, where the M 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：US11505854B2

公开(公告)日：2022-11-22

申请号：US16831307

申请日：2020-03-26

Applicant: HYUNDAI MOTOR COMPANY ,  KIA MOTORS CORPORATION ,  JFE STEEL CORPORATION

Inventor： Hak Soo Kim ,  Kohsuke Ashizuka ,  Akio Kobayashi ,  Naomichi Nakamura ,  Masashi Fujinaga ,  Toshio Maetani ,  Hirofumi Enokido ,  Hisashi Sudo

IPC: B22F1/00 ,  C22C38/16 ,  C22C38/12 ,  B22F1/10

Abstract: The present disclosure relates to an iron-based prealloy powder having excellent strength and processability, and an iron-based alloy powder for powder metallurgy and a sinter-forged member using the same. The iron-based prealloy powder for powder metallurgy according to an embodiment of the present disclosure includes 0.5 to 5.0 wt % of Cu, 0.1 to 0.5 wt % of Mo, and a balance of Fe and other inevitable impurities. A Cu content (Cu %) and a Mo content (Mo %) satisfy the following Relational Equation (1): 0.3×Cu %+3×Mo %≤2.7  (1).

公开(公告)号：US11414731B2

公开(公告)日：2022-08-16

申请号：US16482120

申请日：2018-01-26

Applicant: JFE STEEL CORPORATION

Inventor： Akio Kobayashi ,  Naomichi Nakamura

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

Abstract: Disclosed is a mixed powder for powder metallurgy including: (a) an iron-based powder containing Si in an amount of 0 mass % to 0.2 mass % and Mn in an amount of 0 mass % to 0.4 mass %, with the balance being Fe and inevitable impurities; and (b) an alloyed steel powder containing Mo in an amount of 0.3 mass % to 4.5 mass %, Si in an amount of 0 mass % to 0.2 mass %, and Mn in an amount of 0 mass % to 0.4 mass %, with the balance being Fe and inevitable impurities, wherein a ratio of (b) the alloyed steel powder to a total of (a) the iron-based powder and (b) the alloyed steel powder is from 50 mass % to 90 mass %, and a ratio of Mo to the total of (a) the iron-based powder and (b) the alloyed steel powder is 0.20 mass % or more and less than 2.20 mass %.

公开(公告)号：US20200316688A1

公开(公告)日：2020-10-08

申请号：US16769611

申请日：2018-12-05

Applicant: JFE Steel Corporation

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

IPC: B22F9/08

Abstract: [Object] Provided is a method for manufacturing atomized metal powder having a high amorphous material fraction by using a water atomizing method.[Solution] A method for manufacturing atomized metal powder in which atomized metal powder having an amorphous material fraction of 90% or more is obtained, the method including ejecting high-pressure water so as to collide with a molten metal stream flowing vertically downward, separating the molten metal stream into metal powder, and cooling the metal powder, in which the high-pressure water collides with the molten metal with a collision pressure of 20 MPa or higher, and in which a temperature of the molten metal and/or a temperature of the high-pressure water are controlled so that the high-pressure water is in a subcritical state or a supercritical state on a collision surface with the molten metal.

公开(公告)号：US10774403B2

公开(公告)日：2020-09-15

申请号：US15533512

申请日：2015-12-08

Applicant: JFE STEEL CORPORATION ,  HYUNDAI MOTOR COMPANY ,  KIA MOTORS CORPORATION

Inventor： Naomichi Nakamura ,  Akio Sonobe ,  Akio Kobayashi

IPC: C22C33/02 ,  B22F3/17 ,  C22C38/16 ,  C22C38/00 ,  B22F1/02 ,  B22F1/00

Abstract: An iron-based alloy powder for powder metallurgy contains 2.0 mass % to 5.0 mass % of Cu, the balance being Fe and incidental impurities. From 1/10 to 8/10 of the Cu is diffusion bonded in powder-form to the surfaces of iron powder that serves as a raw material for the iron-based alloy powder, and the remainder of the Cu is contained in this iron powder as a pre-alloy. The iron-based alloy powder has superior compressibility to conventional Cu pre-alloyed iron-based alloy powders and enables production of a high strength sinter-forged member even when sintered at a lower temperature than conventional iron-based alloy powders containing mixed Cu powder.

公开(公告)号：US10710155B2

公开(公告)日：2020-07-14

申请号：US15739839

申请日：2016-09-16

Applicant: JFE STEEL CORPORATION

Inventor： Takuya Takashita ,  Akio Kobayashi ,  Naomichi Nakamura ,  Itsuya Sato

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

Abstract: Provided is a mixed powder for powder metallurgy having a chemical system not using Ni which causes non-uniform metallic microstructure in a sintered body. A mixed powder for powder metallurgy comprises: a partially diffusion alloyed steel powder in which Mo diffusionally adheres to a particle surface of an iron-based powder; a Cu powder; and a graphite powder, wherein the mixed 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 the balance consisting of Fe and inevitable impurities, and the partially diffusion alloyed steel powder has: a mean particle diameter of 30 μm to 120 μm; a specific surface area of less than 0.10 m2/g; and a circularity of particles with a diameter in a range from 50 μm to 100 μm of 0.65 or less.