Patents by Inventor Takuya TAKASHITA
Takuya TAKASHITA has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 11884996Abstract: 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.Type: GrantFiled: April 10, 2020Date of Patent: January 30, 2024Assignee: JFE STEEL CORPORATIONInventors: Nao Nasu, Takuya Takashita, Akio Kobayashi
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Publication number: 20240011134Abstract: Alloy powder includes particles. The particles include specific particles. Each of the specific particles has a surface layer on which a divided trace is formed, the divided trace being a mark at which molten alloy is divided; and the divided trace has at least a hill-like ridge aggregate structure or a combination of a crater structure and the hill-like ridge aggregate structure, the hill-like ridge aggregate structure being an aggregate of a plurality of hill-like ridges.Type: ApplicationFiled: September 19, 2023Publication date: January 11, 2024Applicant: TOKIN CORPORATIONInventors: Akiri URATA, Yosuke IMANO, Makoto YAMAKI, Naoto ONISHI, Masato KUNO, Takuya TAKASHITA, Makoto NAKASEKO
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Patent number: 11866810Abstract: Alloy powder comprises particles. The particles include specific particles. Each of the specific particles has a surface layer on which a divided trace is formed.Type: GrantFiled: September 16, 2022Date of Patent: January 9, 2024Assignee: TOKIN CORPORATIONInventors: Akiri Urata, Yosuke Imano, Makoto Yamaki, Naoto Onishi, Masato Kuno, Takuya Takashita, Makoto Nakaseko
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Publication number: 20240001441Abstract: A method for producing water-atomized metal powder by dividing a molten metal stream, which is falling in a vertical direction, by spraying cooling water that impinges on the molten metal stream includes a step of spraying the cooling water at a spray pressure of 10 MPa or more and a spread angle in a range of 5° to 30° from each of three or more cooling water discharge ports arranged remote from the falling molten metal stream. The droplet diameter of the cooling water: 100 ?m or less, the convergence angle: 5° to 10°, and the water/molten steel ratio: 50 or more.Type: ApplicationFiled: August 26, 2021Publication date: January 4, 2024Applicant: JFE Steel CorporationInventors: Makoto Nakaseko, Shigeru Unami, Takuya Takashita, Naoki Yamamoto
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Patent number: 11814707Abstract: This soft magnetic powder is represented by composition formula FeaSibBcPdCue with the exception of unavoidable impurities. In the composition formula, a, b, c, d and e satisfy 79?a?84.5 at %, 0?b<6 at %, 4?c?10 at %, 4<d?11 at %, 0.2?e<0.4 at %, and a+b+c+d+e=100 at %.Type: GrantFiled: January 26, 2018Date of Patent: November 14, 2023Assignees: TOKIN CORPORATION, JFE STEEL CORPORATIONInventors: Akiri Urata, Miho Chiba, Mineo Muraki, Makoto Nakaseko, Takuya Takashita
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Patent number: 11795532Abstract: 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.Type: GrantFiled: October 10, 2019Date of Patent: October 24, 2023Assignee: JFE Steel CorporationInventors: Makoto Nakaseko, Shigeru Unami, Akio Kobayashi, Takuya Takashita
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Publication number: 20230290552Abstract: Provided is an iron-based powder for dust core with which a dust core with low iron loss and high insulation properties can be obtained. In the iron-based powder for dust core of the present disclosure, a median particle size calculated based on cumulative volume frequency of particles of the iron-based powder for dust core is 150 ?m or less, and cumulative volume frequency of the particles with an aspect ratio of 0.70 or less is 70% or less, and a median aspect ratio calculated based on cumulative volume frequency is 0.60 or more.Type: ApplicationFiled: April 27, 2021Publication date: September 14, 2023Applicant: JFE STEEL CORPORATIONInventors: Naoki YAMAMOTO, Takuya TAKASHITA, Makoto NAKASEKO, Shigeru UNAMI
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Publication number: 20230212719Abstract: 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<6 at %, 0 at %<c?10 at %, 4 at %<d?11 at %, 0.2 at %?e?0.53 at %, 0 at %?f?4 at %, a+b+c+d+e+f=100 at %, a degree of crystallinity is more than 10% by volume, and an Fe crystallite diameter of the Fe-based nanocrystalline alloy powder is 50 nm or less.Type: ApplicationFiled: February 27, 2023Publication date: July 6, 2023Applicant: JFE STEEL CORPORATIONInventors: Naoki YAMAMOTO, Takuya TAKASHITA, Makoto NAKASEKO, Akio KOBAYASHI, Akiri URATA, Miho CHIBA
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Patent number: 11654487Abstract: 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.Type: GrantFiled: October 10, 2019Date of Patent: May 23, 2023Assignee: JFE STEEL CORPORATIONInventors: Makoto Nakaseko, Naomichi Nakamura, Akio Kobayashi, Takuya Takashita
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Publication number: 20230108224Abstract: Provided is an iron-based soft magnetic powder for dust cores that enables production of a dust core having high density and low iron loss. An iron-based soft magnetic powder for dust cores comprises: an iron-based soft magnetic powder; a condensed aluminum phosphate layer on particle surfaces of the iron-based soft magnetic powder; and a silicone resin layer on a surface of the condensed aluminum phosphate layer, wherein the condensed aluminum phosphate layer is a continuous coating, and a total mass of the condensed aluminum phosphate layer and the silicone resin layer is 0.60 mass % or less with respect to 100 mass % of a total mass of the iron-based soft magnetic powder, the condensed aluminum phosphate layer, and the silicone resin layer.Type: ApplicationFiled: December 18, 2020Publication date: April 6, 2023Applicant: JFE STEEL CORPORATIONInventors: Takuya TAKASHITA, Takechika NAKAMURA
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Publication number: 20230085762Abstract: Alloy powder comprises particles. The particles include specific particles. Each of the specific particles has a surface layer on which a divided trace is formed.Type: ApplicationFiled: September 16, 2022Publication date: March 23, 2023Applicant: TOKIN CORPORATIONInventors: Akiri URATA, Yosuke IMANO, Makoto YAMAKI, Naoto ONISHI, Masato KUNO, Takuya TAKASHITA, Makoto NAKASEKO
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Patent number: 11600414Abstract: 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<6 at %, 0 at %<c?10 at %, 4 at %<d?11 at %, 0.2 at %?e?0.53 at %, 0 at %?f?4 at %, a+b+c+d+e+f=100 at %, a particle size is 1 mm or less, and a median of circularity of particles constituting the soft magnetic powder is 0.4 or more and 1.0 or less.Type: GrantFiled: July 25, 2019Date of Patent: March 7, 2023Assignee: JFE STEEL CORPORATIONInventors: Naoki Yamamoto, Takuya Takashita, Makoto Nakaseko, Akio Kobayashi, Akiri Urata, Miho Chiba
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Publication number: 20220380873Abstract: 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.Type: ApplicationFiled: November 12, 2020Publication date: December 1, 2022Applicant: JFE STEEL CORPORATIONInventors: Kohsuke ASHIZUKA, Nao NASU, Takuya TAKASHITA, Shigeru UNAMI
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Publication number: 20220331860Abstract: Provided is an alloyed steel powder for powder metallurgy which has excellent compressibility and can be used to produce a sintered body that obtains improved strength simply by sintering. The alloyed steel powder for powder metallurgy contains Cu: 1.0 mass % or more and 8.0 mass % or less, Mo: more than 0.50 mass % and 2.00 mass % or less, and at least one selected from the group consisting of V: 0.05 mass % or more and 0.50 mass % or less, Nb: 0.02 mass % or more and 0.40 mass % or less, and Ti: 0.02 mass % or more and 0.40 mass % or less, with the balance consisting of Fe and inevitable impurities.Type: ApplicationFiled: June 16, 2020Publication date: October 20, 2022Applicant: JFE STEEL CORPORATIONInventors: Kohsuke ASHIZUKA, Nao NASU, Takuya TAKASHITA, Shigeru UNAMI
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Patent number: 11441212Abstract: 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 ?m or more, and among particles contained in the alloyed steel powder, those particles having an equivalent circular diameter of 50 ?m to 200 ?m have a number average of solidity of 0.70 to 0.86, the solidity being defined as (particle cross-sectional area/envelope-inside area).Type: GrantFiled: November 30, 2018Date of Patent: September 13, 2022Assignee: JFE STEEL CORPORATIONInventors: Takuya Takashita, Akio Kobayashi, Naomichi Nakamura
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Publication number: 20220219229Abstract: 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.Type: ApplicationFiled: April 10, 2020Publication date: July 14, 2022Applicant: JFE STEEL CORPORATIONInventors: Nao NASU, Takuya TAKASHITA, Akio KOBAYASHI
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Patent number: 11364541Abstract: 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 ?m or more, and among particles contained in the partially diffusion-alloyed steel powder, those particles having an equivalent circular diameter of 50 ?m to 200 ?m have a number average of solidity of 0.70 to 0.86, the solidity being defined as (particle cross-sectional area/envelope-inside area).Type: GrantFiled: November 30, 2018Date of Patent: June 21, 2022Assignee: JFE STEEL CORPORATIONInventors: Takuya Takashita, Akio Kobayashi, Naomichi Nakamura
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Publication number: 20220161321Abstract: Provided is a steel strip joining method that can appropriately evaluate risk of a fracture in a joined part and prevent a fracture more reliably. An iron-based mixed powder for powder metallurgy comprises: an iron-based alloy powder; and an alloying powder, wherein the iron-based alloy powder contains Mo: 0.2 mass % or more and 1.5 mass % or less, the alloying powder contains a graphite powder and a copper powder, a ratio of a mass of the graphite powder to a total mass of the iron-based alloy powder and the alloying powder is 0.10 mass % to 1.0 mass %, a ratio of a mass of the copper powder to the total mass of the iron-based alloy powder and the alloying powder is 0.5 mass % to 3.0 mass %, and the copper powder has an average particle size of 25 ?m or less, and a specific surface area of 0.30 m2/g or more.Type: ApplicationFiled: February 10, 2020Publication date: May 26, 2022Applicant: JFE STEEL CORPORATIONInventors: Takuya TAKASHITA, Nao NASU, Akio KOBAYASHI
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Publication number: 20220044859Abstract: Provided is an iron-based powder for dust cores that has high apparent density and enables producing dust cores having high green density. An iron-based powder for dust cores comprises a maximum particle size of 1 mm or less, wherein a median circularity of particles constituting the iron-based powder for dust cores is 0.40 or more, and a uniformity number in Rosin-Rammler equation is 0.30 or more and 90.0 or less.Type: ApplicationFiled: February 10, 2020Publication date: February 10, 2022Applicant: JFE STEEL CORPORATIONInventors: Naoki YAMAMOTO, Takuya TAKASHITA, Makoto NAKASEKO, Akio KOBAYASHI, Shigeru UNAMI
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Patent number: 11236411Abstract: 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%.Type: GrantFiled: March 22, 2019Date of Patent: February 1, 2022Assignee: JFE STEEL CORPORATIONInventors: Nao Nasu, Takuya Takashita, Akio Kobayashi