Patents by Inventor Masafumi Azuma

Masafumi Azuma 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).

  • Patent number: 10504631
    Abstract: A plant abnormality predict detection system for detectably monitoring an indication of abnormality in an atomic power generation plant is provided with: a data storage unit which stores plant operation data including an instrument parameter measured in the atomic power generation plant; and a monitoring and control unit which, on the basis of the plant operation data, detects an indication of abnormality in the atomic power generation plant, wherein the atomic power generation plant performs a base-load operation so that the instrument parameter has a prescribed target value, and wherein the monitoring and control unit, on the basis of past plant operation data, sets a normal range W that is a range in which the instrument parameter at the current time transitions normally, and detects an indication of abnormality when the instrument parameter at the current time exceeds the normal range W that has been set.
    Type: Grant
    Filed: June 22, 2016
    Date of Patent: December 10, 2019
    Assignee: MITSUBISHI HEAVY INDUSTRIES, LTD.
    Inventors: Kenji Mashio, Takae Yamashita, Takashi Azuma, Susumu Shiizuka, Junichi Nishitani, Masafumi Utsumi, Jun Shibuya
  • Publication number: 20190338389
    Abstract: When a zone surrounded by a grain boundary that is measured to be 5.0° or more by an EBSD analysis is assumed to be a grain, and when a K value is a value obtained by multiplying an average value of Image Qualities in a grain by 10?3, a Y value is an average crystal misorientation (°) in the grain, a metallic phase 1 is a metallic phase the K value of which is less than 4.000, a metallic phase 2 is a metallic phase the K value of which is 4.000 or more and the Y value of which is 0.5 to 1.0, a metallic phase 3 is a metallic phase the K value of which is 4.000 or more and the Y value of which is less than 0.5, and a metallic phase 4 is a metallic phase that falls under none of metallic phases 1 to 3, there is provided a steel sheet that has a predetermined chemical composition and includes a microstructure including, in area percent, a metallic phase 1: 1.0% or more and less than 35.0%, a metallic phase 2: 30.0% or more and 80.0% or less, a metallic phase 3: 5.0% or more and 50.
    Type: Application
    Filed: January 27, 2017
    Publication date: November 7, 2019
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Yuri TODA, Masafumi AZUMA, Akihiro UENISHI, Eisaku SAKURADA, Tatsuo YOKOI, Genichi SHIGESATO
  • Patent number: 10465272
    Abstract: Provided is a high-strength hot-dip galvanized steel sheet having excellent plating adhesion, formability, and hole expandability with an ultimate tensile strength of 980 MPa or more, the hot-dip galvanized steel sheet comprising a hot-dip galvanized layer formed on a surface of a base steel sheet. The base steel sheet contains, by mass %, C: 0.05% to 0.4%; Si: 0.01% to 3.0%; Mn: 0.1% to 3.0%; Al: 0.01 to 2.0%; in which Si+Al>0.5%, P: limited to 0.04% or less; S: limited to 0.05% or less; N: limited to 0.01% or less; and a balance including Fe and inevitable impurities, a microstructure of the base steel sheet contains 40% or more by total volume fraction of martensite and bainite, 8% or more by volume fraction of residual austenite, and a balance of the microstructure being ferrite or ferrite and 10% or less by volume fraction of pearlite.
    Type: Grant
    Filed: September 6, 2017
    Date of Patent: November 5, 2019
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Chisato Wakabayashi, Masafumi Azuma, Nobuhiro Fujita, Kohichi Sano
  • Publication number: 20190330721
    Abstract: A steel sheet includes a predetermined chemical composition, and includes a steel structure represented by, in a volume fraction, tempered martensite and bainite: 70% or more and less than 92% in total, retained austenite: 8% or more and less than 30%, ferrite: less than 10%, fresh martensite: less than 10%, and pearlite: less than 10%. A number density of iron-base carbides in tempered martensite and lower bainite is 1.0×106 (pieces/mm2) or more, and an effective crystal grain diameter of tempered martensite and bainite is 5 ?m or less.
    Type: Application
    Filed: September 21, 2016
    Publication date: October 31, 2019
    Applicant: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Kunio HAYASHI, Masafumi AZUMA
  • Patent number: 10407760
    Abstract: A hot-dip galvanized steel sheet includes: a steel sheet; and a plated layer on a surface of the steel sheet, a microstructure contains, by volume fraction, equal to or more than 20% and equal to or less than 99% in total of one or two of martensite and bainite, a residual structure contains one or two of ferrite, residual austenite of less than 8% by volume fraction, and pearlite of equal to or less than 10% by volume fraction, tensile strength is equal to or greater than 980 MPa, the plated layer is a hot-dip galvanized layer which contains oxides including one or two or more of Si, Mn, and Al, contains equal to or less than 15 mass % of Fe, and a remainder including Zn, Al, and unavoidable impurities, and when a cross section including the steel sheet and the hot-dip galvanized layer is seen in a sheet thickness direction, a projected area ratio is equal to or more than 10% and equal to or less than 90%.
    Type: Grant
    Filed: September 28, 2012
    Date of Patent: September 10, 2019
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Masafumi Azuma, Chisato Wakabayashi, Takayuki Nozaki, Manabu Takahashi, Nobuhiro Fujita
  • Publication number: 20190211427
    Abstract: A steel sheet according to an aspect of the present invention includes a predetermined chemical composition; in which a metallographic structure in a ¼ t portion contains residual austenite of 4 volume % to 70 volume %; [Mn]?/[Mn]ave>1.5 is satisfied in the ¼ t portion; f?s/f??0.30 and [C]×[Mn]?0.15 are satisfied in the ¼ t portion.
    Type: Application
    Filed: September 21, 2016
    Publication date: July 11, 2019
    Applicant: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Kohichi SANO, Masafumi AZUMA, Mutsumi SAKAKIBARA, Akihiro UENISHI, Koutarou HAYASHI
  • Publication number: 20190169729
    Abstract: A hot-dip galvanized steel sheet includes: a predetermined chemical composition; and a steel structure represented by: in terms of area ratio, polygonal ferrite: 10% or less; upper bainite: 20% or less; retained austenite: 5% or less; and martensite: 70% or more, in which: martensite having Fe carbides at a number density of 1×106/mm2 or more is contained by 50% or more, in terms of area ratio, with respect to the entire amount of martensite; and the steel structure has an average effective crystal grain diameter of 5.0 ?m or less.
    Type: Application
    Filed: July 15, 2016
    Publication date: June 6, 2019
    Applicant: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Takafumi YOKOYAMA, Kunio HAYASHI, Masafumi AZUMA, Eisaku SAKURADA, Hiroyuki KAWATA, Genki ABUKAWA
  • Publication number: 20190161820
    Abstract: There is provided a hot-rolled steel sheet in which a composition contains: in mass %, C: 0.01% to 0.2%; Si: 2.5% or less; Mn: 4.0% or less; P: 0.10% or less; S: 0.03% or less; Al: 0.001% to 2.0%; N: 0.01% or less; 0: 0.01% or less; Ti: 0.01 to 0.30%; and the balance being composed of iron and impurities and a structure is composed of by volume fraction, 90% or more of tempered martensite with an average aspect ratio of 2 or less, or 90% or more in total of both tempered martensite and lower bainite.
    Type: Application
    Filed: January 31, 2019
    Publication date: May 30, 2019
    Applicant: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Akifumi SAKAKIBARA, Tatsuo YOKOI, Hiroshi SHUTO, Yuuki KANZAWA, Masafumi AZUMA
  • Patent number: 10301699
    Abstract: A hot-stamped part includes a chemical composition represented by, in mass %: C: 0.120% to 0.400%; Si: 0.005% to 2.000%; Mn or Cr, or both thereof: 1.00% to 3.00% in total; Al: 0.005% to 0.100%; B: 0.0003% to 0.0020%; P: not more than 0.030%; S: not more than 0.0100%; O: not more than 0.0070%; N: not more than 0.0070%; Ti: 0% to 0.100%; Nb: 0% to 0.100%; V: 0% to 0.100%; Ni: 0% to 2.00%; Cu: 0% to 2.00%; Mo: 0% to 0.50%; Ca or REM, or both thereof: 0% to 0.0300% in total; and the balance: Fe and impurities, and a structure represented by: an area fraction of martensite or bainite, or both thereof: not less than 95% in total; a coverage factor of prior austenite grain boundary by iron-based carbides: not more than 80%; and a number density of iron-based carbides in prior austenite grains: not less than 45/?m2.
    Type: Grant
    Filed: September 12, 2014
    Date of Patent: May 28, 2019
    Assignee: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Kaoru Kawasaki, Masafumi Azuma, Genki Abukawa
  • Patent number: 10260124
    Abstract: There is provided a hot-rolled steel sheet in which a composition contains: in mass %, C: 0.01% to 0.2%; Si: 2.5% or less; Mn: 4.0% or less; P: 0.10% or less; S: 0.03% or less; Al: 0.001% to 2.0%; N: 0.01% or less; O: 0.01% or less; Ti: 0.01 to 0.30%; and the balance being composed of iron and impurities and a structure is composed of by volume fraction, 90% or more of tempered martensite with an average aspect ratio of 2 or less, or 90% or more in total of both tempered martensite and lower bainite.
    Type: Grant
    Filed: May 13, 2014
    Date of Patent: April 16, 2019
    Assignee: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Akifumi Sakakibara, Tatsuo Yokoi, Hiroshi Shuto, Yuuki Kanzawa, Masafumi Azuma
  • Patent number: 10196726
    Abstract: Provided is a high-strength hot-rolled steel sheet consisting of, in mass %, C: 0.01% to 0.2%, Si: 0% to 2.5%, Mn: 0% to 4.0%, Al: 0% to 2.0%, N: 0% to 0.01%, Cu: 0% to 2.0%, Ni: 0% to 2.0%, Mo: 0% to 1.0%, V: 0% to 0.3%, Cr: 0% to 2.0%, Mg: 0% to 0.01%, Ca: 0% to 0.01%, REM: 0% to 0.1%, B: 0% to 0.01%, P: less than or equal to 0.10%, S: less than or equal to 0.03%, O: less than or equal to 0.01%, one or both of Ti and Nb: 0.01% to 0.30% in total, and the balance being Fe and inevitable impurities. The steel sheet has a structure in which a total volume fraction of tempered martensite or lower bainite is 90% or more, a dislocation density thereof is greater than or equal to 5×1013 (1/m2) and less than or equal to 1×1016 (1/m2) and 1×106 (numbers/mm2) or more iron-based carbides are included therein.
    Type: Grant
    Filed: February 25, 2014
    Date of Patent: February 5, 2019
    Assignee: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Masafumi Azuma, Hiroshi Shuto, Tatsuo Yokoi, Yuuki Kanzawa, Akihiro Uenishi
  • Publication number: 20180237881
    Abstract: A steel sheet includes: a predetermined chemical composition; and a steel structure containing, in are a fraction, 2% or more of ferrite and bainite, in which an average dislocation density in the ferrite and an average dislocation density in the bainite are both h3×1012 m/m3 to 1×1014 m/m3, and an average grain diameter of the ferrite and the bainite is 5 ?m or less.
    Type: Application
    Filed: August 21, 2015
    Publication date: August 23, 2018
    Applicant: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Riki OKAMOTO, Hiroyuki KAWATA, Masafumi AZUMA, Akihiro UENISHI, Naoki MARUYAMA
  • Publication number: 20180230581
    Abstract: A steel sheet includes: a predetermined chemical composition; and a steel structure represented by, in area %, first martensite in which two or more iron carbides each having a circle-equivalent diameter of 2 nm to 500 nm are contained in each lath: 20% to 95%, ferrite: 15% or less, retained austenite: 15% or less, and the balance: bainite, or second martensite in which less than two iron carbides each having a circle-equivalent diameter of 2 nm to 500 nm are contained in each lath, or the both of these, in which the total area fraction of ND//<111> orientation grains and ND//<100> orientation grains is 40% or less, and the content of solid-solution C is 0.44 ppm or more.
    Type: Application
    Filed: August 31, 2015
    Publication date: August 16, 2018
    Applicant: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Riki OKAMOTO, Hiroyuki KAWATA, Masafumi AZUMA, Akihiro UENISHI, Naoki MARUYAMA
  • Publication number: 20180209006
    Abstract: A steel sheet according to an aspect of the present invention has predetermined chemical composition, in which a structure at a thickness ¼ portion includes, in terms of volume ratios, tempered martensite: 30% to 70% and one or both of ferrite and bainite: a total of 20% to 70%, in the structure at the thickness ¼ portion, a volume ratio of residual austenite is less than 10%, a volume ratio of fresh martensite is 10% or less, a volume ratio of pearlite is 10% or less, and a total volume ratio of the residual austenite, the fresh martensite, and the pearlite is 15% or less, a number density of iron-based carbides having a major axis of 5 nm or more in the tempered martensite at the thickness ¼ portion is 5×107 particles/mm2 or more, a ratio of the number of ?-type carbides in the number of the iron-based carbides having the major axis of 5 nm or more at the thickness ¼ portion is 20% or more, and a tensile strength is 780 MPa or higher.
    Type: Application
    Filed: July 13, 2015
    Publication date: July 26, 2018
    Applicant: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Yuri TODA, Masafumi AZUMA, Akihiro UENISHI, Hiroyuki KAWATA, Naoki MARUYAMA, Genichi SHIGESATO
  • Publication number: 20180202019
    Abstract: A steel sheet according to an aspect of the present invention has predetermined chemical composition, in which a structure at a thickness ¼ portion includes, in terms of volume ratios, tempered martensite: 70% or more and one or both of ferrite and bainite: a total of less than 20%, in the structure at the thickness ¼ portion, a volume ratio of residual austenite is less than 10%, a volume ratio of fresh martensite is 10% or less, a volume ratio of pearlite is 10% or less, and a total volume ratio of the residual austenite, the fresh martensite, and the pearlite is 15% or less, a number density of iron-based carbides having a major axis of 5 nm or more in the tempered martensite at the thickness ¼ portion is 5×107 particles/mm2 or more, a ratio of the number of ?-type carbides in the number of the iron-based carbides having the major axis of 5 nm or more at the thickness ¼ portion is 20% or more, and a tensile strength is 780 MPa or higher.
    Type: Application
    Filed: July 13, 2015
    Publication date: July 19, 2018
    Applicant: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Yuri TODA, Masafumi AZUMA, Akihiro UENISHI, Hiroyuki KAWATA, Naoki MARUYAMA, Genichi SHIGESATO
  • Patent number: 10023929
    Abstract: A hot-rolled steel sheet has a composition containing: in mass %, C: 0.01 to 0.2%; Si: 2.5% or less; Mn: 4.0% or less; P: 0.10% or less; S: 0.03% or less; Al: 0.001 to 2.0%; N: 0.01% or less; and O: 0.01% or less, and one kind or a total of two kinds of Ti and Nb for 0.01 to 0.30%. An average effective crystal grain diameter at a sheet thickness ¼ part is 10 ?m or less, and an average effective crystal grain diameter at a part of a range of 50 ?m from a surface is 6 ?m or less. A structure of the steel sheet is tempered martensite or lower bainite, and a volume fraction thereof is 90% or more as a total.
    Type: Grant
    Filed: May 16, 2014
    Date of Patent: July 17, 2018
    Assignee: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Hiroshi Shuto, Masafumi Azuma, Akifumi Sakakibara, Yuuki Kanzawa, Ken Kimura
  • Patent number: 10023947
    Abstract: High strength steel plate with an ultimate tensile strength of 900 MPa or more which is excellent in hydrogen embrittlement resistance characterized in that, in the structure of the steel plate, (a) by volume fraction, ferrite is present in 10 to 50%, bainitic ferrite and/or bainite in 10 to 60%, and tempered martensite in 10 to 50%, and (b) iron-based carbides which contain Si or Si and Al in 0.1% or more are present in 4×108 (particles/mm3) or more.
    Type: Grant
    Filed: November 30, 2010
    Date of Patent: July 17, 2018
    Assignee: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Masafumi Azuma, Noriyuki Suzuki, Naoki Maruyama, Akinobu Murasato, Yasuharu Sakuma, Hiroyuki Kawata, Chisato Wakabayashi
  • Publication number: 20180171429
    Abstract: A heat-treated steel sheet member having a chemical including, by mass %: C: 0.05 to 0.50%; Si: 0.50 to 5.0%; Mn: 1.5 to 4.0%; P: 0.05% or less; S: 0.05% or less; N: 0.01% or less; Ti: 0.01 to 0.10%; B: 0.0005 to 0.010%; Cr: optional amounts of Ni, Cu, Mo, V, Ca, Al, Nb, and REM, with the balance: Fe and impurities. The steel sheet member has a microstructure comprising: mainly martensite; and retained austenite of which a volume ratio is 5.0% or higher, a number density of retained carbide in the steel sheet member having circle-equivalent diameters of 0.1 mm or larger is 4.0×103/mm2 or lower, [(log fg0?log fg(0.02))/0.02<20.0] is satisfied when mechanical properties are measured using a sheet specimen specified in ASTM E8, a tensile strength is 1.4 GPa or higher, and a total elongation is 8.0% or higher.
    Type: Application
    Filed: April 7, 2016
    Publication date: June 21, 2018
    Inventors: Yoshihiro SUWA, Shinichiro TABATA, Masafumi AZUMA, Kazuo HIKIDA
  • Patent number: 10000829
    Abstract: A hot-rolled steel sheet includes a specified chemical composition and includes a steel structure represented by an area ratio of ferrite being 5% to 50%, an area ratio of bainite composed of an aggregate of bainitic ferrite whose grain average misorientation is 0.4° to 3° being 50% to 90%, and a total area ratio of martensite, pearlite, and retained austenite being 5% or less.
    Type: Grant
    Filed: April 14, 2014
    Date of Patent: June 19, 2018
    Assignee: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Yuri Toda, Masafumi Azuma, Akihiro Uenishi, Genichi Shigesato
  • Publication number: 20180135155
    Abstract: A steel sheet for heat treatment having a chemical composition including, by mass %: C: 0.05 to 0.50%; Si: 0.50 to 5.0%; Mn; 1.5 to 4.0%; P: 0.05% or less; S: 0.05% or less; N: 0.01% or less; Ti: 0.01 to 0.10%; B: 0.0005 to 0.010%; Cr: 0 to 1.0%; Ni: 0 to 2.0%; Cu: 0 to 1.0%; Mo: 0 to 1.0%; V: 0 to 1.0%; Ca: 0 to 0.01%; Al: 0 to 1.0%; Nb: 0 to 1.0%; REM: 0 to 0.1%; and the balance: Fe and impurities, wherein a maximum height roughness Rz on a surface of the steel sheet is 3.0 to 10.0 ?m, and a number density of carbide being present in the steel sheet and having circle-equivalent diameters of 0.1 ?m or larger is 8.0×103/mm2 or lower.
    Type: Application
    Filed: April 7, 2016
    Publication date: May 17, 2018
    Inventors: Yoshihiro SUWA, Shinichiro TABATA, Masafumi AZUMA, Kazuo HIKIDA