Patents by Inventor Koutarou Hayashi

Koutarou Hayashi 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).

  • Publication number: 20220145415
    Abstract: The present invention relates to a cold rolled steel sheet containing C: 0.15% or more and 0.40% or less, Si: 0.50% or more and 4.00% or less, Mn: 1.00% or more and 4.00% or less, and sol. Al: 0.001% or more and 2.000% or less, having a metallic structure consisting of 35 to 65 area % of ferrite phases, 35 to 65 area % of hard second phases, and 0 to 5 area % of remaining phases, wherein 60% or more of the ferrite phases are recrystallized ferrite phases, an average crystal grain size defined by 15° grain boundaries is 5.0 ?m or less, a maximum connecting rate of the hard second phases is 10% or more, and a two-dimensional isoperimetric constant of the hard second phases is 0.20 or less.
    Type: Application
    Filed: March 31, 2020
    Publication date: May 12, 2022
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Shohei YABU, Koutarou HAYASHI, Akihiro UENISHI
  • Publication number: 20220119902
    Abstract: This hot-rolled steel sheet has a predetermined chemical composition, in which a metal microstructure contains, by area %, 3.0% or more of residual austenite, has a ratio L52/L7 of a length L52 of a grain boundary having a crystal orientation difference of 52° to a length L7 of a grain boundary having a crystal orientation difference of 7° about a <110> direction of 0.10 or more and 0.18 or less, has a standard deviation of a Mn concentration of 0.60 mass % or less, and has a tensile strength of 980 MPa or more.
    Type: Application
    Filed: January 30, 2020
    Publication date: April 21, 2022
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Hiroshi SHUTO, Koutarou HAYASHI, Hiroshi KAIDO, Akifumi SAKAKIBARA, Jun ANDO, Tetsu ASATO
  • Publication number: 20220081748
    Abstract: This hot-rolled steel sheet has a predetermined chemical composition, in which a metallographic structure contains, by area %, 3.0% or more of retained austenite, has a ratio L52/L7 of a length L52 of a grain boundary having a crystal misorientation of 52° to a length L7 of a grain boundary having a crystal misorientation of 7° about a <110> direction of more than 0.18, has a standard deviation of a Mn concentration of 0.60 mass % or less, and has a tensile strength of 1180 MPa or more.
    Type: Application
    Filed: January 30, 2020
    Publication date: March 17, 2022
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Koutarou HAYASHI, Hiroshi SHUTO, Kazumasa TSUTSUI, Hiroshi KAIDO
  • Publication number: 20220064139
    Abstract: The present disclosure provides, for example, a method that can produce a fluorolactone compound from hexafluoropropylene oxide or the like in a single step. The present disclosure relates to a method for producing a compound represented by formula (1): wherein two R1 are the same and each is a fluorine atom or a fluoroalkyl group, the method comprising step A of reacting a compound represented by formula (2): wherein R1 is as defined above, with a compound represented by formula (3): wherein R31, R32, and R33 are the same or different and each is a hydrogen atom or an alkyl group, or two of them are optionally linked to each other to form a ring optionally having one or more substituents, and a compound represented by formula (4-1) or the like: wherein R41, R42, R43, and R44 are the same or different and each is a hydrogen atom ox an alkyl group, or two of them are optionally linked to each other to form a ring optionally having one or more substituents.
    Type: Application
    Filed: November 8, 2021
    Publication date: March 3, 2022
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Moe HOSOKAWA, Koutarou HAYASHI, Yoshihiro YAMAMOTO, Akiyoshi YAMAUCHI, Makoto MATSUURA, Yosuke KISHIKAWA
  • Publication number: 20220042149
    Abstract: The cold-rolled steel sheet having a high bake hardening amount and excellent bendability after bake hardening according to the present invention has a predetermined composition, and contains 20% or more and 70% or less of ferrite and 30% or more of tempered martensite in terms of area ratio, in which a sum of ferrite and tempered martensite is 90% or more, and in a case where a microstructure image of 30 ?m×30 ?m obtained by photographing a structure at a magnification of 2,000-fold is disposed in an xy coordinate system having a sheet thickness direction as an x-axis and a rolling direction as a y-axis, the microstructure image is divided into 1024 pieces in an x-axis direction and 1024 pieces in a y-axis direction to form 1024×1024 divided regions, and a two-dimensional image is created by performing double gradation by assuming a value of “1” in each of the divided regions in one case where the structure is ferrite and assuming a value of “0” in the other cases, a heterogeneity ? when two-dimensional disc
    Type: Application
    Filed: October 4, 2019
    Publication date: February 10, 2022
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Hiroshi KAIDO, Mai NAGANO, Koutarou HAYASHI
  • Patent number: 11242583
    Abstract: A steel sheet includes, as a chemical composition, by mass %: C: 0.05-0.30%; Si: 0.2-2.0%; Mn: 2.0-4.0%; Al: 0.001-2.000%; P: 0.100% or less; S: 0.010% or less; N: 0.010% or less; Ti: 0-0.100%; Nb: 0-0.100%; V: 0-0.100%; Cu: 0-1.00%; Ni: 0-1.00%; Mo: 0-1.00%; Cr: 0-1.00%; W: 0-0.005%; Ca: 0-0.005%; Mg: 0-0.005%; a rare earth element (REM): 0-0.010%; B: 0-0.0030%; and a remainder of Fe and impurities, in which a metallographic structure contains, by area ratio, 95% or more of a hard structure and 0-5% of residual austenite, by mass % in a cross section in a thickness direction, C1/C2 which is a ratio of an upper limit C1 of a Mn content to a lower limit C2 of the Mn content is 1.5 or less, and a bake-hardening amount BH is 150 MPa or less.
    Type: Grant
    Filed: November 8, 2018
    Date of Patent: February 8, 2022
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Mai Nagano, Koutarou Hayashi, Akihiro Uenishi
  • Publication number: 20220025497
    Abstract: A galvannealed steel sheet according to one aspect of the present invention has a hot-dip galvannealed layer on at least one surface of the steel sheet, and the steel sheet has a predetermined chemical composition, in which the steel sheet contains 10% or more and 90% or less of ferrite, and 10% or more of tempered martensite and tempered bainite in terms of an area ratio, a sum of the ferrite, the tempered martensite, and the tempered bainite is 90% or more, carbides having a major axis of 50 nm or more and 300 nm or less are contained in grains of the ferrite in a number density of 20/?m2 or more, and a two-dimensional homogeneous dispersion ratio S of Mn is 0.75 or more and 1.30 or less.
    Type: Application
    Filed: October 4, 2019
    Publication date: January 27, 2022
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Mai NAGANO, Koutarou HAYASHI, Akihiro UENISHI
  • Patent number: 11225701
    Abstract: A hot dip galvanized steel sheet and hot dip galvannealed steel sheet improved in uniform ductility and local ductility, yield strength and tensile strength, and low temperature impact property, characterized by having a predetermined chemical composition, having a metal structure containing, by volume %, retained austenite: over 5.0% and tempered martensite: over 5.0%, having retained austenite containing C: 0.85 mass % or more, and having a ratio [C]?gb/[P]?gb of an amount of segregation of C (number of atoms/nm2): [C]?gb to an amount of segregation of P (number of atoms/nm2): [P]?gb at prior austenite grain boundaries of 4.0 or more.
    Type: Grant
    Filed: March 30, 2018
    Date of Patent: January 18, 2022
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Jun Haga, Kohichi Sano, Koutarou Hayashi, Kunio Hayashi, Masaharu Kameda, Akihiro Uenishi, Hiroyuki Kawata
  • Publication number: 20210381086
    Abstract: This hot-rolled steel sheet has a predetermined chemical composition. The metallographic structure at a sheet thickness ¼ depth from a surface and at a center position in a sheet width direction in a sheet width cross section parallel to a rolling direction contains, by area %, 77.0% to 97.0% of bainite and tempered martensite in total, 0% to 5.0% of ferrite, 0% to 5.0% of pearlite, 3.0% or more of residual austenite, and 0% to 10.0% of martensite. The average grain size of the metallographic structure excluding the residual austenite is 7.0 ?m or less. The C concentration in the residual austenite is 0.5 mass % or more. The number density of iron-based carbides having a diameter of 20 nm or more is 1.0×106 carbides/mm2 or more.
    Type: Application
    Filed: October 21, 2019
    Publication date: December 9, 2021
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Hiroshi SHUTO, Akifumi SAKAKIBARA, Shinsuke KAI, Koutarou HAYASHI, Hiroshi KAIDO
  • Publication number: 20210371392
    Abstract: The present disclosure provides, for example, a method that can produce a fluorolactone compound from hexafluoropropylene oxide or the like in a single step.
    Type: Application
    Filed: August 10, 2021
    Publication date: December 2, 2021
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Moe HOSOKAWA, Koutarou HAYASHI, Yoshihiro YAMAMOTO, Akiyoshi YAMAUCHI, Yosuke KISHIKAWA, Yuuki SUZUKI, Akitoshi OGATA, Makoto MATSUURA
  • Publication number: 20210269903
    Abstract: What is provided is a high-strength steel sheet including, by mass %: C: 0.05% to 0.15%; Si: 1.5% or less; Mn: 2.00% to 5.00%; P: 0.100% or less; S: 0.010% or less; Al: 0.001% to 2.000%; N: 0.010% or less; and a remainder of Fe and impurities, in which Ceq defined by Ceq=C+Si/90+Mn/100+1.5P+3S is less than 0.21, the high-strength steel sheet contains martensite in an area ratio of 98% or more, and a residual structure is in an area ratio of 2% or less, a two-dimensional homogeneous dispersion ratio S defined by S=Sy2/Sx2 (Sx2 is a dispersion value of Mn concentration profile data in a sheet width direction, and Sy2 is a dispersion value of the Mn concentration profile data in a sheet thickness direction) is 0.85 or more and 1.20 or less, and a tensile strength is 1200 MPa or more.
    Type: Application
    Filed: July 26, 2019
    Publication date: September 2, 2021
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Mai NAGANO, Koutarou HAYASHI, Akihiro UENISHI
  • Publication number: 20210164082
    Abstract: What is provided is a high-strength steel sheet having a large bake hardening amount and a uniform bake hardenability is provided according to the present invention, the high-strength steel sheet comprising, by mass %: C: 0.13% to 0.40%; Si: 0.500% to 3.000%; Mn: 2.50% to 5.00%; P: 0.100% or less; S: 0.010% or less; Al: 0.001% to 2.000%; N: 0.010% or less; and a remainder consisting of Fe and impurities, wherein martensite is 95% or more in an area ratio, and residual structure is 5% or less in an area ratio, a ratio C1/C2 of an upper limit C1 (mass %) of Si concentrations to a lower limit C2 (mass %) of the Si concentrations in a cross section in a thickness direction is 1.25 or less, precipitates having a major axis of 0.05 ?m or more and 1.00 ?m or less and an aspect ratio of 1:3 or more are included in a number density of 30/?m2 or more, and a tensile strength is 1300 MPa or more.
    Type: Application
    Filed: July 26, 2019
    Publication date: June 3, 2021
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Mai NAGANO, Koutarou HAYASHI, Akihiro UENISHI
  • Publication number: 20210053906
    Abstract: An object of the present disclosure is to provide a method for producing a tetraalkylammonium nitrite that is capable of efficiently producing the desired product, and/or increasing the purity of the desired product. The object is achieved by a method for producing a tetraalkylammonium nitrite including step A of reacting, in a solvent, a tetraalkylammonium salt with a metal salt that is not a silver salt, to form a tetraalkylammonium nitrite and an insoluble metal salt.
    Type: Application
    Filed: March 26, 2019
    Publication date: February 25, 2021
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Michiaki OKADA, Koutarou HAYASHI, Satoru YONEDA
  • Publication number: 20210017622
    Abstract: A hot dip galvanized steel sheet and hot dip galvannealed steel sheet improved in uniform ductility and local ductility, yield strength and tensile strength, and low temperature impact property, characterized by having a predetermined chemical composition, having a metal structure containing, by volume %, retained austenite: over 5.0% and tempered martensite: over 5.0%, having retained austenite containing C: 0.85 mass % or more, and having a ratio [C]?gb/[P]?gb of an amount of segregation of C (number of atoms/nm2): [C]?gb to an amount of segregation of P (number of atoms/nm2): [P]?gb at prior austenite grain boundaries of 4.0 or more.
    Type: Application
    Filed: March 30, 2018
    Publication date: January 21, 2021
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Jun HAGA, Kohichi SANO, Koutarou HAYASHI, Kunio HAYASHI, Masaharu KAMEDA, Akihiro UENISHI, Hiroyuki KAWATA
  • Publication number: 20210002741
    Abstract: A steel sheet including, in mass %, C: 0.05% or more and 0.30% or less, Si: 0.05% or more and 6.00% or less, Mn: 1.50% or more and 10.00% or less, and the balance: Fe and impurities, a steel sheet structure is composed of, in area ratio, 15% or more and 80% or less of ferrite and 20% or more and 85% or less in total of a hard structure composed of any one of bainite, martensite, or retained austenite, or any combination thereof, and to a steel sheet thickness t, an area ratio of a maximum coupled ferrite region in a region from a t/2 position at the steel sheet thickness center to a position at a depth of 3t/8 from a surface is 80% or more in area ratio to a total ferrite area, and a two-dimensional isoperimetric constant of the maximum coupled ferrite region is 0.35 or less.
    Type: Application
    Filed: March 30, 2018
    Publication date: January 7, 2021
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Shohei YABU, Koutarou HAYASHI, Akihiro UENISHI
  • Publication number: 20200332397
    Abstract: A steel sheet includes, as a chemical composition, by mass %: C: 0.05% to 0.30%; Si: 0.2% to 2.0%; Mn: 2.0% to 4.0%; Al: 0.001% to 2.000%; P: 0.100% or less; S: 0.010% or less; N: 0.010% or less; Ti: 0% to 0.100%; Nb: 0% to 0.100%; V: 0% to 0.100%; Cu: 0% to 1.00%; Ni: 0% to 1.00%; Mo: 0% to 1.00%; Cr: 0% to 1.00%; W: 0% to 0.005%; Ca: 0% to 0.005%; Mg: 0% to 0.005%; a rare earth element (REM): 0% to 0.010%; B: 0% to 0.0030%; and a remainder of Fe and impurities, in which a metallographic structure contains, by area ratio, 95% or more of a hard structure and 0% to 5% of residual austenite, by mass % in a cross section in a thickness direction, C1/C2 which is a ratio of an upper limit C1 of a Mn content to a lower limit C2 of the Mn content is 1.5 or less, and a bake-hardening amount BH is 150 MPa or less.
    Type: Application
    Filed: November 8, 2018
    Publication date: October 22, 2020
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Mai NAGANO, Koutarou HAYASHI, Akihiro UENISHI
  • Patent number: 10774405
    Abstract: Steel has a chemical composition that contains 0.050% to 0.40% of C, 0.50% to 3.0% of Si, 3.0% to 8.0% of Mn, and 0.001% to 3.0% of sol. Al, by mass %, and has a metallographic structure that contains 10% to 40% of austenite in terms of % by volume. The average concentration of C in austenite is 0.30% by 0.60%, by mass %, structure uniformity, which is represented by a value obtained by subtracting the minimum value from the maximum value of Vickers hardness that is measured, in the metallographic structure is 30 Hv or less, and the tensile strength is 900 MPa to 1800 MPa.
    Type: Grant
    Filed: January 6, 2014
    Date of Patent: September 15, 2020
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Koutarou Hayashi, Akira Seki, Kazuya Mishio, Shuhei Shimokawa
  • Patent number: 10745775
    Abstract: A steel sheet for galvannealed steel contains, by mass %, C: 0.25 to 0.70%, Si: 0.25 to 2.50%, Mn: 1.00 to 5.00%, Al: 0.005 to 3.50%, P: 0.15% or less, S: 0.03% or less, N £ 0.02%, O £ 0.01%, and optionally one or more selected from Ti, Nb, V, Cr, Mo, Cu, Ni, B, Ca, REM, Mg, W, Zr, Sb, Sn, As, Te, Y, Hf and Co, a balance being Fe and impurities. The microstructure consists of, by vol. %, retained g: 10.0 to 60.0%, high-temperature tempered martensite3 5.0%, low-temperature tempered martensite3 5.0%, fresh martensite £ 10.0%, a: 0 to 15.0%, P: 0 to 10.0%, a balance being bainite. Total volume ratio of tempered martensite and bainite is 30.0% or more, tensile strength is 1470 MPa or more, tensile strength×uniform elongation is 13000 MPa % or more, and tensile strength×local elongation is 5000 MPa % or more.
    Type: Grant
    Filed: June 10, 2016
    Date of Patent: August 18, 2020
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Kohichi Sano, Jun Haga, Koutarou Hayashi, Hiroyuki Kawata, Riki Okamoto, Akihiro Uenishi
  • Patent number: 10711322
    Abstract: A steel sheet for hot pressing includes: a specific chemical composition; and a steel structure comprising ferrite and cementite and represented, in area %: a total area ratio of bainite and martensite: 0% to 10%; and an area ratio of cementite: 1% or more; and a concentration of Mn in the cementite is 5% or more.
    Type: Grant
    Filed: February 5, 2019
    Date of Patent: July 14, 2020
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Koutarou Hayashi, Toshinobu Nishibata
  • Publication number: 20200071801
    Abstract: A high strength steel sheet containing a large amount of Mn which has bendability suitable as a material for auto part use and a method of producing the same are provided. A high strength steel sheet comprising a center part in a sheet thickness and a softened surface layer part on one surface or both surfaces of the center part in the sheet thickness, characterized in that, the center part in the sheet thickness has an average Mn concentration of greater than 4.0 mass % and less than 10.0 mass %, each softened surface layer part has a thickness of 0.1% to 30% of the sheet thickness, and the softened surface layer part has an average Mn concentration of 2.5 mass % or less, a recrystallization rate of 90% or more, and recrystallized structures with an average crystal grain size of 0.1 ?m or more and 40 ?m or less.
    Type: Application
    Filed: April 27, 2018
    Publication date: March 5, 2020
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Shohei YABU, Koutarou HAYASHI, Genki ABUKAWA, Akihiro UENISHI