Patents by Inventor Daisuke Motoya

Daisuke Motoya 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: 20180237879
    Abstract: A stainless steel pipe has a composition of, in mass %: C: up to 0.02%; Si: 0.05 to 1.00%; Mn: 0.1 to 1.0%; P: up to 0.030%; S: up to 0.002%; Ni: 5.5 to 8%; Cr: 10 to 14%; Mo: 2 to 4%; V: 0.01 to 0.10%; Ti: 0.05 to 0.3%; Nb: up to 0.1%; Al: 0.001 to 0.1%; N: up to 0.05%; Cu: up to 0.5%; Ca: 0 to 0.008%; Mg: 0 to 0.05%; B: 0 to 0.005%; and balance Fe and impurities. The pipe having a microstructure including martensite and, by volume fraction, 12 to 18% retained austenite. The martensite has prior austenite grains of a crystal grain size number lower than 8.0 in accordance with ASTM E112. The stainless steel pipe has a yield strength of 550 to 700 MPa.
    Type: Application
    Filed: June 1, 2016
    Publication date: August 23, 2018
    Inventors: Daisuke MOTOYA, Taro OE
  • Patent number: 9771628
    Abstract: Provided is a duplex stainless steel having a high strength and a high toughness. A stainless steel according to the present invention includes: a chemical composition containing, in mass percent, C: at most 0.030%, Si: 0.20 to 1.00%, Mn: at most 8.00%, P: at most 0.040%, S: at most 0.0100%, Cu: more than 2.00% and at most 4.00%, Ni: 4.00 to 8.00%, Cr: 20.0 to 30.0%, Mo: at least 0.50% and less than 2.00%, N: 0.100 to 0.350%, and sol. Al: at most 0.040%, the balance being Fe and impurities; and a structure, wherein a rate of ferrite in the structure is 30 to 70%, and a hardness of the ferrite in the structure is at least 300 Hv10gf.
    Type: Grant
    Filed: February 10, 2012
    Date of Patent: September 26, 2017
    Assignee: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Daisuke Motoya, Masahiko Hamada, Hisashi Amaya, Hiroyuki Nagayama, Kenta Yamada
  • Patent number: 9579870
    Abstract: A welded joint of duplex stainless steel, which can suppress precipitation ? phase under high heat input welding, is excellent in SCC resistance under high-temperature chloride environments. A weld metal of the welded joint contains, in mass percent, C: at most 0.030%, Si: 0.20 to 1.00%, Mn: at most 8.00%, P: at most 0.040%, S: at most 0.0100%, Cu: at most 2.00%, Ni: 7.00 to 12.00%, Cr: 20.0 to 30.0%, Mo: 1 to 4%, N: 0.100 to 0.350%, sol. Al: at most 0.040%, and O: at most 0.035%, the balance being Fe and impurities. The weld metal satisfies Expressions (1) and (3): 2.2Cr+7Mo+3Cu>66??(1) Cr+11Mo+10Ni?12(Cu+30N)<100??(3) where a content (mass percent) of each element in one of the base metal and weld metal is used for each element in Expressions (1) and (3).
    Type: Grant
    Filed: February 10, 2012
    Date of Patent: February 28, 2017
    Assignee: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Hiroyuki Nagayama, Kenta Yamada, Masahiko Hamada, Daisuke Motoya, Hisashi Amaya
  • Patent number: 9555496
    Abstract: A process for producing a welded joint, which includes a weld metal having high strength and high toughness, and containing fewer blowholes, includes the steps of: preparing a base material containing, by mass %, not less than 10.5% of Cr; and subjecting the base material to GMA welding using a shielding gas containing 1 to 2 volume % or 35 to 50 volume % of CO2 gas, and the balance being inert gas, thereby forming a weld metal includes, by mass %, C: not more than 0.080%, Si: 0.20 to 1.00%, Mn: not more than 8.00%, P: not more than 0.040%, S: not more than 0.0100%, Cu: not more than 2.0%, Cr: 20.0 to 30.0%, Ni: 7.00 to 12.00%, N: 0.100 to 0.350%, O: 0.02 to 0.11%, sol. Al: not more than 0.040%, at least one of Mo: 1.00 to 4.00% and W: 1.00 to 4.00%, and the balance being Fe and impurities.
    Type: Grant
    Filed: March 27, 2013
    Date of Patent: January 31, 2017
    Assignee: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Kenta Yamada, Masahiko Hamada, Daisuke Motoya, Shinjiro Nakatsuka, Hisashi Amaya, Hideki Takabe
  • Publication number: 20150056005
    Abstract: Provided is a process for producing a welded joint which includes a weld metal having high strength and high toughness, and containing fewer blowholes. The process for producing a welded joint according to the present embodiment includes the steps of: preparing a base material containing, by mass %, not less than 10.5% of Cr; and subjecting the base material to GMA welding using a shielding gas containing 1 to 2 volume % or 35 to 50 volume % of CO2 gas, and the balance being inert gas, thereby forming a weld metal includes, by mass %, C: not more than 0.080%, Si: 0.20 to 1.00%, Mn: not more than 8.00%, P: not more than 0.040%, S: not more than 0.0100%, Cu: not more than 2.0%, Cr: 20.0 to 30.0%, Ni: 7.00 to 12.00%, N: 0.100 to 0.350%, O: 0.02 to 0.11%, sol. Al: not more, than 0.040%, at least one of Mo: 1.00 to 4.00% and W: 1.00 to 4.00%, and the balance being Fe and impurities.
    Type: Application
    Filed: March 27, 2013
    Publication date: February 26, 2015
    Applicant: Nippon Steel & Sumitomo Metal Corporation
    Inventors: Kenta Yamada, Masahiko Hamada, Daisuke Motoya, Shinjiro Nakatsuka, Hisashi Amaya, Hideki Takabe
  • Publication number: 20130316193
    Abstract: A welded joint of duplex stainless steel, which can suppress precipitation of ? phase under high heat input welding, is excellent in SCC resistance under high-temperature chloride environments. A weld metal of the welded joint contains, in mass percent, C: at most 0.030%, Si: 0.20 to 1.00%, Mn: at most 8.00%, P: at most 0.040%, S: at most 0.0100%, Cu: at most 2.00%, Ni: 7.00 to 12.00%, Cr: 20.0 to 30.0%, Mo: 1 to 4%, N: 0.100 to 0.350%, sol. Al: at most 0.040%, and O: at most 0.035%, the balance being Fe and impurities. The weld metal satisfies Expressions (1) and (3): 2.2Cr+7Mo+3Cu>66??(1) Cr+11Mo+10Ni?12(Cu+30N)<100??(3) where a content (mass percent) of each element in one of the base metal and weld metal is used for each element in Expressions (1) and (3).
    Type: Application
    Filed: February 10, 2012
    Publication date: November 28, 2013
    Inventors: Hiroyuki Nagayama, Kenta Yamada, Masahiko Hamada, Daisuke Motoya, Hisashi Amaya
  • Publication number: 20130315776
    Abstract: A duplex stainless steel, which can suppress precipitation of a ? phase under high heat input welding, is excellent in SCC resistance under high-temperature chloride environments and has a high strength. The duplex stainless steel includes a chemical composition containing, in mass percent, C: at most 0.030%, Si: 0.20 to 1.00%, Mn: at most 8.00%, P: at most 0.040%, S: at most 0.0100%, Cu: more than 2.00% and at most 4.00%, Ni: 4.00 to 8.00%, Cr: 20.0 to 28.0%, Mo: 0.50 to 2.00%, N: 0.100 to 0.350%, and sol. Al: at most 0.040%, the balance being Fe and impurities, and satisfying Expression (1) and Expression (2); a structure having a ferrite rate of at least 50%; and a yield strength of at least 550 MPa or more: 2.
    Type: Application
    Filed: February 10, 2012
    Publication date: November 28, 2013
    Applicant: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Kenta Yamada, Hiroyuki Nagayama, Masahiko Hamada, Daisuke Motoya, Hisashi Amaya
  • Publication number: 20130312880
    Abstract: Provided is a duplex stainless steel having a high strength and a high toughness. A stainless steel according to the present invention includes: a chemical composition containing, in mass percent, C: at most 0.030%, Si: 0.20 to 1.00%, Mn: at most 8.00%, P: at most 0.040%, S: at most 0.0100%, Cu: more than 2.00% and at most 4.00%, Ni: 4.00 to 8.00%, Cr: 20.0 to 30.0%, Mo: at least 0.50% and less than 2.00%, N: 0.100 to 0.350%, and sol. Al: at most 0.040%, the balance being Fe and impurities; and a structure, wherein a rate of ferrite in the structure is 30 to 70%, and a hardness of the ferrite in the structure is at least 300 Hv10gf.
    Type: Application
    Filed: February 10, 2012
    Publication date: November 28, 2013
    Applicant: NIPPON STEEL & SUMITOMO METAL CORORATION
    Inventors: Daisuke Motoya, Masahiko Hamada, Hisashi Amaya, Hiroyuki Nagayama, Kenta Yamada