Patents by Inventor Takehiro Ohno

Takehiro Ohno 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: 10221474
    Abstract: A method of producing a Ni-based super heat-resistant alloy in which a hot working material is subjected to hot working with a mold is provided. The hot working material consists of, in mass%, 0.001 to 0.050% of C, 1.0% to 4.0% of Al, 3.0% to 7.0% of Ti, 12% to 18% of Cr, 12% to 30% of Co, 1.5% to 5.5% of Mo, 0.5% to 2.5% of W, 0.001% to 0.050% of B, 0.001% to 0.100% of Zr, 0% to 0.01% of Mg, 0% to 5% of Fe, 0% to 3% of Ta, 0% to 3% of Nb, and the remainder of Ni and impurities. The method includes: heating and holding the hot working material in a temperature range of 950° C. to 1150° C. for 1 hour or longer; and performing hot working on the material with the mold that is heated to a temperature range of 800° C. to 1150° C.
    Type: Grant
    Filed: March 24, 2016
    Date of Patent: March 5, 2019
    Assignee: HITACHI METALS, LTD.
    Inventors: Shinichi Kobayashi, Tomonori Ueno, Takehiro Ohno
  • Patent number: 10196723
    Abstract: A production method for an Fe—Ni based heat-resistant superalloy inhibits abnormal grain growth and yields a fine crystal grain structure having an ASTM crystal grain size number of 9 or greater. The production method comprises at least a hot working step in which a material having a prescribed composition is subjected to hot working, wherein the hot working step includes at least a step in which the above material of 930 to 1010° C. is subjected to hot working so that the relation of (effective strain)?0.139×(effective strain rate(/sec))?0.30 is satisfied in the entirety of the above material.
    Type: Grant
    Filed: March 18, 2015
    Date of Patent: February 5, 2019
    Assignee: Hitachi Metals, Ltd.
    Inventors: Chuya Aoki, Takehiro Ohno
  • Patent number: 10131980
    Abstract: A method of producing a Ni-based superalloy is provided. A hot working material is used and consisting of a specific composition and has a solvus temperature of a ?? phase of 1050° C. or more. The method includes: performing heating in a temperature of 980° C. to 1050° C. with an upper limit of ?30° C. from the solvus temperature of the ?? phase, for 10 hours or longer; and performing hot working on the material at a working speed of a strain rate of 2.0/second or more in the above temperature range.
    Type: Grant
    Filed: March 24, 2016
    Date of Patent: November 20, 2018
    Assignee: HITACHI METALS, LTD.
    Inventors: Shinichi Kobayashi, Tomonori Ueno, Takehiro Ohno
  • Publication number: 20180100223
    Abstract: A method of producing a Ni-based superalloy is provided. A hot working material is used and consisting of a specific composition and has a solvus temperature of a ?? phase of 1050° C. or more. The method includes: performing heating in a temperature of 980° C. to 1050° C. with an upper limit of ?30° C. from the solvus temperature of the ?? phase, for 10 hours or longer; and performing hot working on the material at a working speed of a strain rate of 2.0/second or more in the above temperature range.
    Type: Application
    Filed: March 24, 2016
    Publication date: April 12, 2018
    Applicant: HITACHI METALS, LTD.
    Inventors: Shinichi KOBAYASHI, Tomonori UENO, Takehiro OHNO
  • Publication number: 20180057921
    Abstract: A method of producing a Ni-based super heat-resistant alloy in which a hot working material is subjected to hot working with a mold is provided. The hot working material consists of, in mass %, 0.001 to 0.050% of C, 1.0% to 4.0% of Al, 3.0% to 7.0% of Ti, 12% to 18% of Cr, 12% to 30% of Co, 1.5% to 5.5% of Mo, 0.5% to 2.5% of W, 0.001% to 0.050% of B, 0.001% to 0.100% of Zr, 0% to 0.01% of Mg, 0% to 5% of Fe, 0% to 3% of Ta, 0% to 3% of Nb, and the remainder of Ni and impurities. The method includes: heating and holding the hot working material in a temperature range of 950° C. to 1150° C. for 1 hour or longer; and performing hot working on the material with the mold that is heated to a temperature range of 800° C. to 1150° C.
    Type: Application
    Filed: March 24, 2016
    Publication date: March 1, 2018
    Applicant: HITACHI METALS, LTD.
    Inventors: Shinichi KOBAYASHI, Tomonori UENO, Takehiro OHNO
  • Patent number: 9903011
    Abstract: There is provided a method for producing a Ni-based heat-resistant superalloy a primary ?? phase with an average particle size of at least 500 nm comprising the steps of: providing a material to be hot-worked having a composition consisting of, by mass, 0.001 to 0.05% C, 1.0 to 4.0% Al, 4.5 to 7.0% Ti, 12 to 18% Cr, 14 to 27% Co, 1.5 to 4.5% Mo, 0.5 to 2.5% W, 0.001 to 0.05% B, 0.001 to 0.1% Zr, and the balance of Ni with inevitable impurities; heating the material to be hot-worked in a temperature having a range of 1,130 to 1,200° C. for at least 2 hours; cooling the material to be hot-worked heated by the heating step to a hot working temperature or less at a cooling rate of at most 0.03° C./second; and subjecting the material to be hot-worked to hot working after the cooling step.
    Type: Grant
    Filed: March 25, 2014
    Date of Patent: February 27, 2018
    Assignee: Hitachi Metals, Ltd.
    Inventors: Jun Sato, Shinichi Kobayashi, Tomonori Ueno, Takehiro Ohno, Chuya Aoki, Eiji Shimohira
  • Patent number: 9828657
    Abstract: There is provided an Ni-base super alloy which is used for airplane engines and gas turbines for power generation and has favorable mechanical properties at high temperature. The Ni-base super alloy contains 0.001 to 0.1 mass % of C, 1.0 to 4.0 mass % of Al, 2.0 to 4.5 mass % of Ti, 12.0 to 18.0 mass % of Cr, 11.1 to 18.0 mass % of Co, 1.2 to 12.0 mass % of Fe, 1.5 to 6.5 mass % of Mo, 0.5 to 6.0 mass % of W, 0.1 to 3.0 mass % of Nb, 0.001 to 0.05 mass % of B, 0.001 to 0.1 mass % of Zr, and Ni and impurities as a remainder.
    Type: Grant
    Filed: September 28, 2015
    Date of Patent: November 28, 2017
    Assignee: HITACHI METALS, LTD.
    Inventors: Ryutaro Abe, Takehiro Ohno, Shinichi Kobayashi, Tomonori Ueno, Chuya Aoki
  • Publication number: 20170275736
    Abstract: There is provided an Ni-base super alloy which is used for airplane engines and gas turbines for power generation and has favorable mechanical properties at high temperature. The Ni-base super alloy contains 0.001 to 0.1 mass % of C, 1.0 to 4.0 mass % of Al, 2.0 to 4.5 mass % of Ti, 12.0 to 18.0 mass % of Cr, 11.1 to 18.0 mass % of Co, 1.2 to 12.0 mass % of Fe, 1.5 to 6.5 mass % of Mo, 0.5 to 6.0 mass % of W, 0.1 to 3.0 mass % of Nb, 0.001 to 0.05 mass % of B, 0.001 to 0.1 mass % of Zr, and Ni and impurities as a remainder.
    Type: Application
    Filed: September 28, 2015
    Publication date: September 28, 2017
    Inventors: Ryutaro ABE, Takehiro OHNO, Shinichi KOBAYASHI, Tomonori UENO, Chuya AOKI
  • Publication number: 20170114435
    Abstract: A production method for an Fe—Ni based heat-resistant superalloy inhibits abnormal grain growth and yields a fine crystal grain structure having an ASTM crystal grain size number of 9 or greater. The production method comprises at least a hot working step in which a material having a prescribed composition is subjected to hot working, wherein the hot working step includes at least a step in which the above material of 930 to 1010° C. is subjected to hot working so that the relation of (effective strain)?0.139×(effective strain rate(/sec))?0.30 is satisfied in the entirety of the above material.
    Type: Application
    Filed: March 18, 2015
    Publication date: April 27, 2017
    Inventors: Chuya AOKI, Takehiro OHNO
  • Publication number: 20160108506
    Abstract: There is provided a method for producing a Ni-based heat-resistant superalloy a primary ?? phase with an average particle size of at least 500 nm comprising the steps of: providing a material to be hot-worked having a composition consisting of, by mass, 0.001 to 0.05% C, 1.0 to 4.0% Al, 4.5 to 7.0% Ti, 12 to 18% Cr, 14 to 27% Co, 1.5 to 4.5% Mo, 0.5 to 2.5% W, 0.001 to 0.05% B, 0.001 to 0.1% Zr, and the balance of Ni with inevitable impurities; heating the material to be hot-worked in a temperature having a range of 1,130 to 1,200° C. for at least 2 hours; cooling the material to be hot-worked heated by the heating step to a hot working temperature or less at a cooling rate of at most 0.03° C./second; and subjecting the material to be hot-worked to hot working after the cooling step.
    Type: Application
    Filed: March 25, 2014
    Publication date: April 21, 2016
    Inventors: Jun Sato, Shinichi Kobayashi, Tomonori Ueno, Takehiro Ohno, Chuya Aoki, Eiji Shimohira
  • Patent number: 8845958
    Abstract: Provided is an Ni-base alloy excellent in strength, ductility and other properties through the resolution of micro-segregation. Also provided is a process for manufacturing an Ni-base alloy containing by mass C:0.15% or less, Si:1% or less, Mn:1% or less, Cr:10 to 24%, Mo+(1/2)W (where Mo may be contained either alone or as an essential component):5 to 17%, Al:0.5 to 1.8%, Ti:1 to 2.5%, Mg:0.02% or less, and either B:0.02% or less and/or Zr:0.2% or less at an Al/(Al+0.56Ti) ratio of 0.45 to 0.70 with the balance consisting of Ni and impurities, which comprises subjecting, at least one time, an Ni-base alloy material which is prepared by vacuum melting and has the above composition to homogenization heat treatment at 1160 to 1220° C. for 1 to 100 hours. The Mo segregation ratio of the alloy is controlled to 1 to 1.17 by the homogenization heat treatment.
    Type: Grant
    Filed: September 25, 2009
    Date of Patent: September 30, 2014
    Assignee: Hitachi Metals, Ltd.
    Inventors: Chuya Aoki, Toshihiro Uehara, Takehiro Ohno
  • Patent number: 8741215
    Abstract: To provide an inexpensive heat-resisting steel for engine valves by causing Fe-based heat-resisting steel to exhibit high temperature strength not inferior to that of Ni-based heat-resisting steel. A heat-resisting steel for engine valves excellent in high temperature strength containing, in % by mass, C: 0.20 to 0.50%, Si: 1.0% or less, Mn: 5.0% or less, P: 0.1 to 0.5%, Ni: 8.0 to 15.0%, Cr: 16.0 to 25.0%, Mo: 2.0 to 5.0%, Cu: 0.5% or less, Nb: 1.0% or less (including 0%), W: 8.0% or less (including 0%), N: 0.02 to 0.2%, B: 0.01% or less, and remnants of Fe and impurities, wherein the heat-resisting steel for engine valves satisfies formulae below: 442P(%)+12Mo(%)+5W(%)+7Nb(%)+328N(%)+171?300??Formula (1) ?38.13P(%)+1.06Mo(%)+0.13W(%)+9.64Nb(%)+13.52N(%)+4.83?0.12??Formula (2).
    Type: Grant
    Filed: April 19, 2010
    Date of Patent: June 3, 2014
    Assignees: Hitachi Metals, Ltd., Honda Motor Co., Ltd.
    Inventors: Katsuhiko Ohishi, Takehiro Ohno, Toshihiro Uehara
  • Patent number: 8444778
    Abstract: Disclosed is a low-thermal-expansion Ni-based super-heat-resistant alloy for a boiler, which has excellent high-temperature strength. The alloy can be welded without the need of carrying out any aging treatment. The alloy has a Vickers hardness value of 240 or less. The alloy comprises (by mass) C in an amount of 0.2% or less, Si in an amount of 0.5% or less, Mn in an amount of 0.5% or less, Cr in an amount of 10 to 24%, one or both of Mo and W in such an amount satisfying the following formula: Mo+0.5 W=5 to 17%, Al in an amount of 0.5 to 2.0%, Ti in an amount of 1.0 to 3.0%, Fe in an amount of 10% or less, and one or both of B and Zr in an amount of 0.02% or less (excluding 0%) for B and in an amount of 0.2% or less (excluding 0%) for Zr, with the remainder being 48 to 78% of Ni and unavoidable impurities.
    Type: Grant
    Filed: August 29, 2008
    Date of Patent: May 21, 2013
    Assignees: Hitachi Metals, Ltd., Babcock-Hitachi Kabushiki Kaisha, Hitachi, Ltd.
    Inventors: Toshihiro Uehara, Takehiro Ohno, Akihiro Toji, Takashi Sato, Gang Bao, Shinya Imano, Hiroyuki Doi
  • Patent number: 8409712
    Abstract: An alloy to be surface-coated, which can keep excellent hardness of 58HRC or above even when the amount of an alloying element added is reduced or even when the alloy is heated to a temperature of as high as 400 to 500° C.; and sliding members produced by forming a hard film on the surface of the alloy. An alloy to be surface-coated, the surface of which is to be covered with a hard film, which alloy contains by mass C: 0.5 to 1.2%, Si: 2.0% or below, Mn: 1.0% or below, Cr: 5.0 to 14.0%, Mo+1/2 W: 0.5 to 5.0%, and N: more than 0.015 to 0.1% with the balance being Fe and impurities, preferably such an alloy which contains by mass C: 0.6 to 0.85%, Si: 0.1 to 1.5%, Mn: 0.2 to 0.8%, Cr: 7.0 to 11.0%, Mo+1/2 W: 1.0 to 4.0%, and N: 0.04 to 0.08%.
    Type: Grant
    Filed: January 16, 2009
    Date of Patent: April 2, 2013
    Assignee: Hitachi Metals Ltd.
    Inventors: Kenji Yokoyama, Kunichika Kubota, Toshihiro Uehara, Takehiro Ohno, Katsuhiko Ohishi
  • Publication number: 20120114964
    Abstract: Provided is a coated-surface sliding part having excellent adhesion of a hard coating, and a method for producing the same part. The coated-surface sliding part is a sliding part wherein a hard coating is formed by physical deposition on the surface of a base material formed from, by mass percent, C 0.5 to 0.8%, Si 0.1 to 1.5%, Mn 0.2 to 1.0%, Cr 8.0 to 13.5%, Mo and/or W 0.5 to 4.0% in terms of (Mo+ 1/2 W), and N 0.01 to 0.1%, with the remainder being Fe and impurities. The physically deposited coating is a titanium metal coating further covered by a diamond-like carbon coating. The method for producing a coated-surface part involves sputtering in order to apply the physically deposited coating, which consists of the titanium metal coating and then the diamond-like carbon coating which forms the surface layer, to the surface of the base material having the aforementioned composition. The base material is preferably subjected to argon gas bombardment prior to application of the physically deposited coating.
    Type: Application
    Filed: July 13, 2010
    Publication date: May 10, 2012
    Applicants: HITACHI METALS, LTD., HITACHI TOOL ENGINEERING, LTD.
    Inventors: Fumiaki Honda, Kenji Yokoyama, Kenichi Inoue, Kunichika Kubota, Toshihiro Uehara, Takehiro Ohno, Katsuhiko Ohishi
  • Publication number: 20120107169
    Abstract: To provide an inexpensive heat-resisting steel for engine valves by causing Fe-based heat-resisting steel to exhibit high temperature strength not inferior to that of Ni-based heat-resisting steel. A heat-resisting steel for engine valves excellent in high temperature strength containing, in % by mass, C: 0.20 to 0.50%, Si: 1.0% or less, Mn: 5.0% or less, P: 0.1 to 0.5%, Ni: 8.0 to 15.0%, Cr: 16.0 to 25.0%, Mo: 2.0 to 5.0%, Cu: 0.5% or less, Nb: 1.0% or less (including 0%), W: 8.0% or less (including 0%), N: 0.02 to 0.2%, B: 0.01% or less, and remnants of Fe and impurities, wherein the heat-resisting steel for engine valves satisfies formulae below: 442P(%)+12Mo(%)+5W(%)+7Nb(%)+328N(%)+171?300??Formula (1) ?38.13P(%)+1.06Mo(%)+0.13W(%)+9.64Nb(%)+13.52N(%)+4.83?0.
    Type: Application
    Filed: April 19, 2010
    Publication date: May 3, 2012
    Inventors: Katsuhiko Ohishi, Takehiro Ohno, Toshihiro Uehara
  • Publication number: 20110171058
    Abstract: Provided is an Ni-base alloy excellent in strength, ductility and other properties through the resolution of micro-segregation. Also provided is a process for manufacturing an Ni-base alloy containing by mass C: 0.15% or less, Si: 1% or less, Mn: 1% or less, Cr: 10 to 24%, Mo+(½)W (where Mo may be contained either alone or as an essential component): 5 to 17%, Al: 0.5 to 1.8%, Ti: 1 to 2.5%, Mg: 0.02% or less, and either B: 0.02% or less and/or Zr: 0.2% or less at an Al/(Al+0.56Ti) ratio of 0.45 to 0.70 with the balance consisting of Ni and impurities, which comprises subjecting, at least one time, an Ni-base alloy material which is prepared by vacuum melting and has the above composition to homogenization heat treatment at 1160 to 1220° C. for 1 to 100 hours. The Mo segregation ratio of the alloy is controlled to 1 to 1.17 by the homogenization heat treatment.
    Type: Application
    Filed: September 25, 2009
    Publication date: July 14, 2011
    Applicant: HITACHI METALS, LTD.
    Inventors: Chuya Aoki, Toshihiro Uehara, Takehiro Ohno
  • Publication number: 20100291407
    Abstract: An alloy to be surface-coated, which can keep excellent hardness of 58HRC or above even when the amount of an alloying element added is reduced or even when the alloy is heated to a temperature of as high as 400 to 500° C.; and sliding members produced by forming a hard film on the surface of the alloy. An alloy to be surface-coated, the surface of which is to be covered with a hard film, which alloy contains by mass C: 0.5 to 1.2%, Si: 2.0% or below, Mn: 1.0% or below, Cr: 5.0 to 14.0%, Mo+1/2 W: 0.5 to 5.0%, and N: more than 0.015 to 0.1% with the balance being Fe and impurities, preferably such an alloy which contains by mass C: 0.6 to 0.85%, Si: 0.1 to 1.5%, Mn: 0.2 to 0.8%, Cr: 7.0 to 11.0%, Mo+1/2 W: 1.0 to 4.0%, and N: 0.04 to 0.08%.
    Type: Application
    Filed: January 16, 2009
    Publication date: November 18, 2010
    Applicant: HITACHI METALS, LTD.
    Inventors: Kenji Yokoyama, Kunichika Kubota, Toshihiro Uehara, Takehiro Ohno, Katsuhiko Ohishi
  • Publication number: 20100226814
    Abstract: Disclosed is a low-thermal-expansion Ni-based super-heat-resistant alloy for a boiler, which has excellent high-temperature strength. The alloy can be welded without the need of carrying out any aging treatment. The alloy has a Vickers hardness value of 240 or less. The alloy comprises (by mass) C in an amount of 0.2% or less, Si in an amount of 0.5% or less, Mn in an amount of 0.5% or less, Cr in an amount of 10 to 24%, one or both of Mo and W in such an amount satisfying the following formula: Mo+0.5 W=5 to 17%, Al in an amount of 0.5 to 2.0%, Ti in an amount of 1.0 to 3.0%, Fe in an amount of 10% or less, and one or both of B and Zr in an amount of 0.02% or less (excluding 0%) for B and in an amount of 0.2% or less (excluding 0%) for Zr, with the remainder being 48 to 78% of Ni and unavoidable impurities.
    Type: Application
    Filed: August 29, 2008
    Publication date: September 9, 2010
    Applicants: HITACHI METALS, LTD., BABCOCK-HITACHI KABUSHIKI KAISHA, HITACHI, LTD.
    Inventors: Toshihiro Uehara, Takehiro Ohno, Akihiro Toji, Takashi Sato, Gang Bao, Shinya Imano, Hiroyuki Doi
  • Patent number: 6776956
    Abstract: Provided is a steel for separators of solid-oxide type fuel cells, which forms oxide films having good electrical conductivity at 700 to 950° C. or so, has good oxidation resistance and, in particular, resistance to exfoliation even in the case of long hours of use, is excellent in impact properties at room temperature, shows a small difference in thermal expansion from the electrolyte, and is inexpensive. This steel for separators of solid-oxide fuel cells includes, by mass %, not more than 0.2% C, not more than 1.0% Si, not more than 1.0% Mn, not more than 2% Ni, 15 to 30% Cr, not more than 1% Al, one or more elements selected from the group of not more than 0.5% Y, not more than 0.2% REM and not more than 1% Zr, and the balance of Fe and unavoidable impurities. In this steel, amounts of S, O, N and B in the unavoidable impurities are restricted to not more than 0.015%, not more than 0.010%, not more than 0.050% and not more than 0.
    Type: Grant
    Filed: April 26, 2002
    Date of Patent: August 17, 2004
    Assignee: Hitachi Metals Ltd.
    Inventors: Toshihiro Uehara, Akihiro Toji, Takehiro Ohno