Patents by Inventor Tetsushi Chida
Tetsushi Chida 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: 10837080Abstract: In a rolled steel bar or rolled wire rod for a cold-forged component having a predetermined chemical composition, Y1 represented by Y1=[Mn]×[Cr] and Y2 represented by Y2=0.134×(D/25.4?(0.50×?[C]))/(0.50×?[C]) satisfy Y1>Y2, the tensile strength is 750 MPa or less, an internal structure is a ferrite-pearlite structure, and the ferrite fraction in the internal structure is 40% or greater. AMOUNT IS 0.Type: GrantFiled: November 13, 2015Date of Patent: November 17, 2020Assignee: NIPPON STEEL CORPORATIONInventors: Naoki Matsui, Yutaka Neishi, Tetsushi Chida, Akihisa Obata, Shoji Hori, Keisuke Chiba
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Patent number: 10829842Abstract: In a rolled steel bar or rolled wire rod for a cold-forged component having a predetermined chemical composition, Y1 represented by Y1=[Mn]×[Cr] and Y2 represented by Y2=0.134×(D/25.4?(0.50×?[C])/(0.50×?[C]) satisfy Y1>Y2, the tensile strength is 750 MPa or less, an internal structure is a ferrite-pearlite structure, and the ferrite fraction in the internal structure is 40% or greater.Type: GrantFiled: November 13, 2015Date of Patent: November 10, 2020Assignee: NIPPON STEEL CORPORATIONInventors: Naoki Matsui, Yutaka Neishi, Tetsushi Chida, Akihisa Obata, Shoji Hori, Keisuke Chiba
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Patent number: 10669604Abstract: A bolt is provided that has high strength and excellent hydrogen embrittlement resistance characteristics. A bolt according to an embodiment of the present invention consists of, in mass %, C: 0.32 to 0.39%, Si: 0.15% or less, Mn: 0.40 to 0.65%, P: 0.020% or less, S: 0.020% or less, Cr: 0.85 to 1.25%, Al: 0.005 to 0.060%, Ti: 0.010 to 0.050%, B: 0.0010 to 0.0030%, N: 0.0015 to 0.0080%, O: 0.0015% or less, Mo: 0 to 0.05%, V: 0 to 0.05%, Cu: 0 to 0.50%, Ni: 0 to 0.30%, and Nb: 0 to 0.05%, with the balance being Fe and impurities. The bolt satisfies Formula (1) and Formula (2), and has a tensile strength of 1000 to 1300 MPa and satisfies Formula (3). 4.9?10C+Si+2Mn+Cr+4Mo+5V?6.1??(1) Mn/Cr?0.55??(2) [dissolved Cr]/Cr?0.Type: GrantFiled: June 27, 2016Date of Patent: June 2, 2020Assignees: NIPPON STEEL CORPORATION, AOYAMA SEISAKUSHO CO., LTD.Inventors: Yutaka Neishi, Makoto Kosaka, Naoki Matsui, Tetsushi Chida, Keisuke Chiba, Hideo Kanisawa, Kazutaka Aoyama, Kazuoki Shibuya, Ryoko Inagaki
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Publication number: 20190003000Abstract: A bolt is provided that has high strength and excellent hydrogen embrittlement resistance characteristics. A bolt according to an embodiment of the present invention consists of, in mass %, C: 0.32 to 0.39%, Si: 0.15% or less, Mn: 0.40 to 0.65%, P: 0.020% or less, S: 0.020% or less, Cr: 0.85 to 1.25%, Al: 0.005 to 0.060%, Ti: 0.010 to 0.050%, B: 0.0010 to 0.0030%, N: 0.0015 to 0.0080%, 0: 0.0015% or less, Mo: 0 to 0.05%, V: 0 to 0.05%, Cu: 0 to 0.50%, Ni: 0 to 0.30%, and Nb: 0 to 0.05%, with the balance being Fe and impurities. The bolt satisfies Formula (1) and Formula (2), and has a tensile strength of 1000 to 1300 MPa and satisfies Formula (3). 4.9?10C+Si+2Mn+Cr+4Mo+5V?6.1 ??(1) Mn/Cr?0.55 ??(2) [dissolved Cr]/Cr?0.Type: ApplicationFiled: June 27, 2016Publication date: January 3, 2019Inventors: Yutaka NEISHI, Makoto KOSAKA, Naoki MATSUI, Tetsushi CHIDA, Keisuke CHIBA, Hideo KANISAWA, Kazutaka AOYAMA, Kazuoki SHIBUYA, Ryoko INAGAKI
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Publication number: 20170335426Abstract: In a rolled steel bar or rolled wire rod for a cold-forged component having a predetermined chemical composition, Y1 represented by Y1=[Mn]×[Cr] and Y2 represented by Y2=0.134×(D/25.4?(0.50×?[C]))/(0.50×?[C]) satisfy Y1>Y2, the tensile strength is 750 MPa or less, an internal structure is a ferrite-pearlite structure, and the ferrite fraction in the internal structure is 40% or greater. AMOUNT IS 0.Type: ApplicationFiled: November 13, 2015Publication date: November 23, 2017Applicant: NIPPON STEEL & SUMITOMO METAL CORPORATIONInventors: Naoki MATSUI, Yutaka NEISHI, Tetsushi CHIDA, Akihisa OBATA, Shoji HORI, Keisuke CHIBA
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Publication number: 20170314107Abstract: In a rolled steel bar or rolled wire rod for a cold-forged component having a predetermined chemical composition, Y1 represented by Y1=[Mn]×[Cr] and Y2 represented by Y2=0.134×(D/25.4?(0.50×?[C])/(0.50×?[C]) satisfy Y1>Y2, the tensile strength is 750 MPa or less, an internal structure is a ferrite-pearlite structure, and the ferrite fraction in the internal structure is 40% or greater.Type: ApplicationFiled: November 13, 2015Publication date: November 2, 2017Applicant: NIPPON STEEL & SUMITOMO METAL CORPORATIONInventors: Naoki MATSUI, Yutaka NEISHI, Tetsushi CHIDA, Akihisa OBATA, Shoji HORI, Keisuke CHIBA
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Patent number: 8951365Abstract: A steel which is excellent in delayed fracture resistance containing, by mass %, C: 0.10 to 0.55%, Si: 0.01 to 3%, and Mn: 0.1 to 2%, further containing one or more of Cr: 0.05 to 1.5%, V: 0.05 to 0.2%, Mo: 0.05 to 0.4%, Nb: 0.001 to 0.05%, Cu: 0.01 to 4%, Ni: 0.01 to 4%, and B: 0.0001 to 0.005%, and having a balance of Fe and unavoidable impurities, the structure being a mainly tempered martensite structure, the surface of the steel being formed with (a) a nitrided layer having a certain thickness range and a nitrogen concentration higher than the nitrogen concentration of the steel by 0.02 mass % or more and (b) a low carbon region having a certain depth range from the surface of the steel and having a carbon concentration of 0.9 time or less the carbon concentration of the steel.Type: GrantFiled: March 11, 2011Date of Patent: February 10, 2015Assignee: Nippon Steel & Sumitomo Metal CorporationInventors: Daisuke Hirakami, Tetsushi Chida, Toshimi Tarui
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Patent number: 8876988Abstract: The present invention provides a steel for nitriding with a composition including, by mass %: C: 0.10% to 0.20%; Si: 0.01% to 0.7%; Mn: 0.2% to 2.0%; Cr: 0.2% to 2.5%; Al: 0.01% to less than 0.19%; V: over 0.2% to 1.0%; Mo: 0% to 0.54%; N: 0.001% to 0.01%; P limited to not more than 0.05%; S limited to not less than 0.2%; and a balance including Fe and inevitable impurities, the composition satisfying 2?[V]/[C]?10, where [V] is an amount of V by mass % and [C] is an amount of C by mass %, in which the steel for nitriding has a microstructure containing bainite of 50% or more in terms of an area percentage.Type: GrantFiled: November 17, 2011Date of Patent: November 4, 2014Assignee: Nippon Steel & Sumitomo Metal CorporationInventors: Tetsushi Chida, Manabu Kubota, Toshimi Tarui, Daisuke Hirakami, Masayuki Hashimura
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Publication number: 20130087250Abstract: The present invention provides a steel for nitriding with a composition including, by mass %: C: 0.10% to 0.20%; Si: 0.01% to 0.7%; Mn: 0.2% to 2.0%; Cr: 0.2% to 2.5%; Al: 0.01% to less than 0.19%; V: over 0.2% to 1.0%; Mo: 0% to 0.54%; N: 0.001% to 0.01%; P limited to not more than 0.05%; S limited to not less than 0.2%; and a balance including Fe and inevitable impurities, the composition satisfying 2?[V]/[C]?10, where [V] is an amount of V by mass % and [C] is an amount of C by mass %, in which the steel for nitriding has a microstructure containing bainite of 50% or more in terms of an area percentage.Type: ApplicationFiled: November 17, 2011Publication date: April 11, 2013Applicant: NIPPON STEEL & SUMITOMO METAL CORPORATIONInventors: Tetsushi Chida, Manabu Kubota, Toshimi Tarui, Daisuke Hirakami, Masayuki Hashimura
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Publication number: 20120298262Abstract: A steel which is excellent in delayed fracture resistance containing, by mass %, C: 0.10 to 0.55%, Si: 0.01 to 3%, and Mn: 0.1 to 2%, further containing one or more of Cr: 0.05 to 1.5%, V: 0.05 to 0.2%, Mo: 0.05 to 0.4%, Nb: 0.001 to 0.05%, Cu: 0.01 to 4%, Ni: 0.01 to 4%, and B: 0.0001 to 0.005%, and having a balance of Fe and unavoidable impurities, the structure being a mainly tempered martensite structure, the surface of the steel being formed with (a) a nitrided layer having a certain thickness range and a nitrogen concentration higher than the nitrogen concentration of the steel by 0.02 mass % or more and (b) a low carbon region having a certain depth range from the surface of the steel and having a carbon concentration of 0.9 time or less the carbon concentration of the steel.Type: ApplicationFiled: March 11, 2011Publication date: November 29, 2012Applicant: NIPPON STEEL CORPORATIONInventors: Daisuke Hirakami, Tetsushi Chida, Toshimi Tarui
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Publication number: 20120291927Abstract: Drawn heat treated steel wire for high strength spring use is provided containing, by mass %, C: 0.67% to less than 0.9%, Si: 2.0 to 3.5%, Mn: 0.5 to 1.2%, Cr: 1.3 to 2.5%, N: 0.003 to 0.007%, and Al: 0.0005% to 0.003%, having Si and Cr satisfying the following formula: 0.3%?Si?Cr?1.2%, and having a balance of iron and unavoidable impurities, having as impurities, P: 0.025% or less and S: 0.025% or less, furthermore having a circle equivalent diameter of undissolved spherical carbides of less than 0.2 ?m, further having, as a metal structure, at least residual austenite in a volume rate of over 6% to 15%, having a prior austenite grain size number of #10 or more, and having a circle equivalent diameter of undissolved spherical carbides of less than 0.2 ?m.Type: ApplicationFiled: July 5, 2011Publication date: November 22, 2012Applicant: NIPPON STEEL CORPORATIONInventors: Masayuki Hashimura, Tetsushi Chida
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Publication number: 20120247618Abstract: A high strength steel material which is excellent in delayed fracture resistance containing, by mass %, C: 0.10 to 0.55%, Si: 0.01 to 3%, and Mn: 0.1 to 2%, further containing one or both of V: 1.5% or less and Mo: 3.0% or less, the contents of V and Mo satisfying V+1/2Mo>0.4%, further containing one or more of Cr: 0.05 to 1.5%, Nb: 0.001 to 0.05%, Cu: 0.01 to 4%, Ni: 0.01 to 4%, and B: 0.0001 to 0.005%, and having a balance of Fe and unavoidable impurities, the structure being a mainly tempered martensite structure, the surface of the steel material being formed with (a) a nitrided layer having a thickness from the surface of the steel material of 200 ?m or more and a nitrogen concentration of 12.0 mass % or less and higher than the nitrogen concentration of the steel material by 0.02 mass % or more and (b) a low carbon region having a depth from the surface of the steel material of 100 ?m or more to 1000 ?m or less and having a carbon concentration of 0.05 mass % or more and 0.Type: ApplicationFiled: March 11, 2011Publication date: October 4, 2012Inventors: Daisuke Hirakami, Tetsushi Chida, Toshimi Tarui
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Publication number: 20120080122Abstract: The present invention lowers the strength before nitriding to improve the machinability, while deepens the effective hardened case of the nitrided case for improving the fatigue strength. It provides steel for nitriding use containing, by mass %, C: 0.05 to 0.30%, Si: 0.003 to 0.50%, Mn: 0.4 to 3.0%, Cr: 0.2 to 0.9%, Al: 0.19 to 0.70%, V: 0.05 to 1.0%, and Mo: 0.05 to 0.50%, having contents of Al and Cr satisfying 0.5%?1.9Al+Cr?1.8%, and having a balance of Fe and unavoidable impurities.Type: ApplicationFiled: June 14, 2010Publication date: April 5, 2012Inventors: Tetsushi Chida, Toshimi Tarui, Daisuke Hirakami
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Publication number: 20110186182Abstract: The present invention relates to a steel material giving more effective case hardening for improving the fatigue strength and is characterized by containing, by mass %, C: 0.01 to 0.3%, Si: less than 0.1%, Mn: 0.4 to 3%, Cr: 0.5 to 3%, and Al: 0.01 to 0.3%, further containing one or both of Mo: 0.2 to 1.5%, and V: 0.05 to 1.0%, having a balance of Fe and unavoidable impurities, and comprising a structure having 50% or more of bainite.Type: ApplicationFiled: October 19, 2009Publication date: August 4, 2011Inventors: Tetsushi Chida, Manabu Kubota, Toshimi Tarui, Daisuke Hirakami