Patents Examined by Deborah Yee
  • Patent number: 9790579
    Abstract: The present invention provides a high tensile strength steel plate having a chemical composition containing, in percent by mass, 0.03% to 0.12% of C, 0.01% to 0.30% of Si, 0.5% to 1.95% of Mn, 0.008% or less of P, 0.005% or less of S, 0.015% to 0.06% of Al, 0.011% to 0.05% of Nb, 0.005% to 0.02% of Ti, 0.001% to 0.006% of N, 0.0005% to 0.003% of Ca, optionally, one or two or more of Cr, Mo, V, Cu, and Ni, in which Ceq is 0.44 or less, Ti/N is 1.5 to 3.5, and parameter formulas composed of specific elements for controlling the sulfide morphology and the degree of center segregation in the steel are satisfied, and the balance being Fe and incidental impurities, in which the hardness of the center segregation area of the steel sheet is further specified.
    Type: Grant
    Filed: March 1, 2012
    Date of Patent: October 17, 2017
    Assignee: JFE Steel Corporation
    Inventors: Masao Yuga, Shigeki Kitsuya, Yusuke Terazawa, Minoru Suwa, Kenji Hayashi
  • Patent number: 9783876
    Abstract: A stainless steel for oil wells which has excellent high-temperature corrosion resistance and can stably obtain a strength of not less than 758 MPa is provided. The stainless steel for oil wells contains, by masse, C: not more than 0.05%, Si: not more than 1.0%, Mn: 0.01 to 1.0%, P: not more than 0.05%, S: less than 0.002%, Cr: 16 to 18%, Mo: 1.8 to 3%, Cu: 1.0 to 3.5%, Ni: 3.0 to 5.5%, Co: 0.01 to 1.0%, Al: 0.001 to 0.1%, O: not more than 0.05%, and N: not more than 0.05%, the balance being Fe and impurities, and satisfies Formulas (1) and (2): Cr+4Ni+3Mo+2Cu?44??(1) Cr+3Ni+4Mo+2Cu/3?46??(2) where each symbol of element in Formulas (1) and (2) is substituted by the content (mass %) of a corresponding element.
    Type: Grant
    Filed: February 27, 2013
    Date of Patent: October 10, 2017
    Assignee: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Shinjiro Nakatsuka, Taro Ohe, Hisashi Amaya, Hideki Takabe, Yohei Otome, Yusaku Tomio, Masanao Seo, Tomohiko Omura, Kunio Kondo
  • Patent number: 9777357
    Abstract: According to aspects of the invention, provided are an Fe—Cr—Al-based stainless steel sheet which has improved manufacturability by improving the toughness of a hot-rolled steel sheet and a cold-rolled steel sheet without deteriorating oxidation resistance at a high temperature and shape stability when used at a high temperature, and a stainless steel foil which is manufactured by rolling the stainless steel sheet. V and B are added in combination to Fe—Cr—Al-based stainless steel in amounts within specified ranges. Specifically, V content is controlled to be 0.010% or more and 0.050% or less and B content is controlled to be 0.0001% or more and 0.0050% or less, in which the relationship {V content (V %)}/{B content (B %)}>10 is satisfied.
    Type: Grant
    Filed: December 5, 2013
    Date of Patent: October 3, 2017
    Assignee: JFE Steel Corporation
    Inventors: Akito Mizutani, Mitsuyuki Fujisawa, Hiroki Ota, Hiroyuki Ogata
  • Patent number: 9777351
    Abstract: The present invention discloses a method for heat treatment of hypereutectoid steel rail, including the following steps: holding the temperature of the steel rail of which temperature is above 900° C. after finish rolling, conducting a first cooling stage for the steel rail at the first cooling speed after the temperature holding to reduce the temperature of railhead surface layer of the steel rail to 700-750° C., conducting a second cooling stage for the steel rail at the second cooling speed to reduce the temperature of railhead surface layer of the steel rail to 550° C., conducting a third cooling stage for the steel rail at the third cooling speed to reduce the temperature of railhead surface layer of the steel rail to 450° C. or less, and continuing to cool the steel rail in the air.
    Type: Grant
    Filed: December 24, 2014
    Date of Patent: October 3, 2017
    Assignee: Pangang Group Panzhihua Iron & Steel Research Institute Co., Ltd.
    Inventors: Ming Zou, Zhenyu Han, Jihai Jia, Hua Guo, Yong Deng, Chunjian Wang, Jun Yuan, Hui Yao
  • Patent number: 9777358
    Abstract: A thick-walled high-strength steel plate with excellent low-temperature toughness (Charpy impact and CTOD properties of a weld bond) in a multilayer weld zone, and a method for manufacturing the steel plate.
    Type: Grant
    Filed: September 4, 2013
    Date of Patent: October 3, 2017
    Assignee: JFE STEEL CORPORATION
    Inventors: Katsuyuki Ichimiya, Masao Yuga, Kenji Hayashi
  • Patent number: 9777355
    Abstract: There are provided a precipitation strengthening type martensitic steel having both a tensile strength of a 1500 MPa class and a high Charpy absorption energy of 30 J or higher, and a manufacturing process thereof. The precipitation strengthening type martensitic steel includes, in terms of mass %, 0.05% or less of C, 0.2% or less of Si, 0.4% or less of Mn, 7.5 to 11.0% of Ni, 10.5 to 13.5% of Cr, 1.75 to 2.5% of Mo, 0.9 to 2.0% of Al, less than 0.1% of Ti, and a remainder of Fe and impurities, and contains 0.1 to 6.0% of austenite in terms of a volume fraction.
    Type: Grant
    Filed: September 19, 2013
    Date of Patent: October 3, 2017
    Assignee: HITACHI METALS, LTD.
    Inventors: Jun Sato, Tomonori Ueno, Eiji Shimohira
  • Patent number: 9758892
    Abstract: A steel sheet for electroplating includes, by mass %, C: 0.0005% to 0.0050%, Si: 0.20% to 1.0%, Mn: 0.40% to 2.5%, P: 0.05% or less, Ti: 0.010% to 0.050%, Nb: 0.010% to 0.040%, B: 0.0005% to 0.0030%, S: 0.02% or less, Al: 0.01% to 0.30%, N: 0.0010% to 0.01%, and the balance including Fe and impurities, in which when Si content is represented by [Si] and Mn content is represented by [Mn], “[Mn]+5[Si]” is 2.0 to 7.0, and the steel sheet has surface property in which an average of displacements of a measurement point obtained based on a moving average of continuous 31 points in total including 15 front points and 15 back points in a cross-sectional profile of a surface obtained by measuring the average of displacements in an evaluation length of 10 ?m or more at an interval of 0.07 ?m, is 0.005 ?m to 0.10 ?m.
    Type: Grant
    Filed: April 12, 2013
    Date of Patent: September 12, 2017
    Assignee: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Hironori Sato, Masao Kurosaki, Masahiro Fuda, Natsuko Sugiura, Yuji Yamaguchi
  • Patent number: 9758848
    Abstract: A high strength steel sheet including, by mass, C: 0.03% or more and 0.25% or less, Si: 0.4% or more and 2.5% or less, Mn: 3.5% or more and 10.0% or less, P: 0.1% or less, S: 0.01% or less, Al: 0.01% or more and 2.5% or less, N: 0.008% or less, Si+Al: 1.0% or more, the balance being Fe and inevitable impurities. The area ratio of ferrite is 30% or more and 80% or less, the area ratio of martensite is 0% or more and 17% or less, the volume fraction of retained austenite is 8% or more, and the average grain size of retained austenite is 2 ?m or less.
    Type: Grant
    Filed: April 20, 2012
    Date of Patent: September 12, 2017
    Assignee: JFE Steel Corporation
    Inventors: Yoshiyasu Kawasaki, Hiroshi Hasegawa, Shinjiro Kaneko, Yasunobu Nagataki
  • Patent number: 9738960
    Abstract: The high strength steel sheet has a chemical composition including 0.08% to 0.20% of C, 0.3% or less of Si, 0.1% to 3.0% of Mn, 0.10% or less of P, 0.030% or less of S, 0.10% or less of Al, 0.010% or less of N, 0.20% to 0.80% of V, and the remainder composed of Fe and incidental impurities on a percent by mass basis, and a microstructure which includes 95% or more of ferrite phase on an area percentage basis, in which fine precipitates are dispersed having a distribution in such a way that the number density of precipitates having a particle size of less than 10 nm is 1.0×105/?m3 or more and the standard deviation of natural logarithm values of precipitate particle sizes with respect to precipitates having a particle size of less than 10 nm is 1.5 or less.
    Type: Grant
    Filed: April 18, 2013
    Date of Patent: August 22, 2017
    Assignee: JFE Steel Corporation
    Inventors: Taro Kizu, Yoshimasa Funakawa, Hidekazu Ookubo, Tokunori Kanemura, Masato Shigemi, Shoji Kasai, Shinji Yamazaki, Yusuke Yasufuku
  • Patent number: 9738957
    Abstract: A wear resistant steel plate that exhibits excellent impact wear resistant properties and that is suitable for use in construction machinery, shipbuilding, steel pipes or tubes, civil engineering, construction and so on, and a method for manufacturing the same. The wear resistant steel plate includes a specific steel composition, where DI* defined by Formula 1 is 100-250, and has a surface layer part containing 90% or more in area ratio of martensite, a Brinell hardness of 450 HBW 10/3000 or more, and a central part in thickness direction of the steel plate containing 70% or more in area ratio of lower bainite, the central part representing a zone extending from a ½ position of the steel plate thickness to distances of 0.5 mm toward both surfaces of the steel plate. DI*=33.85×(0.1×C)0.5×(0.7×Si+1)×(3.33×Mn+1)×(0.35×Cu+1)×(0.36×Ni+1)×(2.16×Cr+1)×(3×Mo+1)×(1.75×V+1)×(1.5×W+1)??Formula 1 where the symbols of elements represent the contents by mass % of the elements, respectively.
    Type: Grant
    Filed: July 29, 2013
    Date of Patent: August 22, 2017
    Assignee: JFE STEEL CORPORATION
    Inventors: Keiji Ueda, Shinichi Miura, Nobuyuki Ishikawa
  • Patent number: 9725782
    Abstract: In a hot stamped steel, when [C] represents an amount of C (mass %), [Si] represents an amount of Si (mass %), and [Mn] represents an amount of Mn (mass %), an expression of 5×[Si]+[Mn])/[C]>10 is satisfied, a metallographic structure includes 80% or more of a martensite in an area fraction, and optionally, further includes one or more of 10% or less of a pearlite in an area fraction, 5% or less of a retained austenite in a volume ratio, 20% or less of a ferrite in an area fraction, and less than 20% of a bainite in an area fraction, TS×?, which is a product of TS that is a tensile strength and ? that is a hole expansion ratio is 50000 MPa·% or more, and a hardness of the martensite measured with a nanoindenter satisfies H2/H1<1.10 and ?HM<20.
    Type: Grant
    Filed: January 11, 2013
    Date of Patent: August 8, 2017
    Assignee: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Toshiki Nonaka, Satoshi Kato, Kaoru Kawasaki, Toshimasa Tomokiyo
  • Patent number: 9718125
    Abstract: The invention relates to a steel plate, the chemical composition of which comprises, the contents being expressed by weight: 0.010%?C?0.20%, 0.06%?Mn?3%, Si?1.5%, 0.005%?Al?1.5%, S?0.030%, P?0.040%, 2.5%?Ti?7.2%, (0.45×Ti)?0.35%?B?(0.45×Ti)+0.70%, and optionally one or more elements chosen from: Ni?1%, Mo?1%, Cr?3%, Nb?0.1%, V?0.1%, the balance of the composition consisting of iron and inevitable impurities resulting from the smelting.
    Type: Grant
    Filed: October 14, 2014
    Date of Patent: August 1, 2017
    Assignee: ArcelorMittal France
    Inventors: Frederic Bonnet, Olivier Bouaziz, Jean-Claude Chevallot
  • Patent number: 9708680
    Abstract: A hot rolled steel sheet for a square column for building structural members, the hot rolled steel sheet having a composition of, in terms of % by mass, C: 0.07 to 0.18%, Mn: 0.3 to 1.5%, P: 0.03% or less, S: 0.015% or less, N: 0.006% or less, Al: 0.01 to 0.06%, and the balance being Fe and unavoidable impurities, and having a microstructure that includes a primary phase constituted of ferrite and a second phase constituted of pearlite or pearlite and bainite, wherein a second phase frequency defined by equation (1) below is 0.20 to 0.42 and a mean crystal grain diameter of the primary phase and the second phase together is 7 to 15 ?m Second phase frequency=(Number of second phase grains intersecting line segments of particular length)/(Number of primary phase grains and second phase grains intersecting line segments of particular length)??(1).
    Type: Grant
    Filed: April 12, 2012
    Date of Patent: July 18, 2017
    Assignee: JFE Steel Corporation
    Inventors: Chikara Kami, Yuta Tamura, Takato Tamai, Shuji Kawamura
  • Patent number: 9708681
    Abstract: A seamless steel pipe has a composition containing, by mass %, C: 0.15 to 0.50%, Si: 0.1 to 1.0%, Mn: 0.3 to 1.0%, P: 0.015% or less, S: 0.005% or less, Al: 0.01 to 0.1%, N: 0.01% or less, Cr: 0.1 to 1.7%, Mo: 0.40 to 1.1%, V: 0.01 to 0.12%, Nb: 0.01 to 0.08%, Ti: 0.03% or less, and B: 0.0005 to 0.003%, a structure composed of a tempered martensite phase as a main phase with a prior austenite grain size of 8.5 or more, and a hardness distribution in which in four portions 90° apart from each other in the circumferential direction, hardness is 295 HV10 or less in any one of an inner surface-side region at 2.54 to 3.81 mm from the inner surface of the pipe, an outer surface side-region at the same distance from the outer surface of the pipe, and a center of the thickness.
    Type: Grant
    Filed: December 18, 2012
    Date of Patent: July 18, 2017
    Assignee: JFE STEEL CORPORATION
    Inventors: Kenichiro Eguchi, Yasuhide Ishiguro, Yukio Miyata
  • Patent number: 9708697
    Abstract: In a steel sheet having a specific chemical composition and having a microstructure including ferrite that is a soft first phase by 20-50% in terms of the area ratio, the remainder being tempered martensite and/or tempered bainite that is a hard second phase, the microstructure of steel of a surface layer section of the steel sheet from the surface to the depth of 100 ?m and a center section of t/4-3t/4 (t is the sheet thickness) is controlled.
    Type: Grant
    Filed: May 29, 2013
    Date of Patent: July 18, 2017
    Assignee: Kobe Steel, Ltd.
    Inventors: Tomokazu Masuda, Katsura Kajihara, Toshio Murakami, Masaaki Miura, Muneaki Ikeda
  • Patent number: 9708678
    Abstract: The invention relates to a method for producing a shaped and at least regionally hardened sheet metal component, particularly a sheet steel component (15), with at least one perforation (16) produced in it, in which method a preform (13) is heated to forming temperature, subsequently shaped and then at least regionally hardened by corresponding cooling, wherein the at least one perforation (16) in the preform (13) is produced during the course of a punching process before the preform (13) is hardened. According to the invention, the metal piece (14) separated from the preform (13) by punching is fed back to its original position or a corresponding position in the perforation (16), remains there for the duration of the quenching process and is only pressed out during or after removal of the sheet steel component (13) from the die (1), in which it is held during quenching.
    Type: Grant
    Filed: July 10, 2013
    Date of Patent: July 18, 2017
    Assignee: Kirchhoff Automotive Deutschland GmbH
    Inventor: Markus Löcker
  • Patent number: 9702030
    Abstract: A precipitation hardening type martensitic stainless steel of an embodiment contains: Cr: 8.5 to 12.5%; Mo: 1 to 2%; Ni: 8.5 to 11.5%; Ti: 0.6 to 1.4%; C: 0.0005 to 0.05%; Al: 0.0005 to 0.25%; Cu: 0.005 to 0.75%; Nb: 0.0005 to 0.3%; Si: 0.005 to 0.75%; Mn: 0.005 to 1%; and N: 0.0001 to 0.03% by mass, and the balance of Fe and unavoidable impurities.
    Type: Grant
    Filed: June 28, 2013
    Date of Patent: July 11, 2017
    Assignee: KABUSHIKI KAISHA TOSHIBA
    Inventors: Reki Takaku, Haruki Ohnishi, Masayuki Yamada, Yoriharu Murata, Kenichi Imai
  • Patent number: 9695488
    Abstract: A steel is used for providing a bolt that has a high strength and still exhibits excellent hydrogen embrittlement resistance. The steel contains C of 0.30% to 0.50%, Si of 1.0% to 2.5%, Mn of 0.1% to 1.5%, P of greater than 0% to 0.015%, S of greater than 0% to 0.015%, Cr of 0.15% to 2.4%, Al of 0.010% to 0.10%, N of 0.001% to 0.10%, Cu of 0.1% to 0.50%, Ni of 0.1% to 1.0%, Ti of 0.05% to 0.2%, and V of 0% to 0.2%, with the remainder including iron and inevitable impurities, in which a ratio [Ni]/[Cu] is 0.5 or more, and a total content [Ti]+[V] is 0.085% to 0.30%.
    Type: Grant
    Filed: November 26, 2012
    Date of Patent: July 4, 2017
    Assignee: Kobe Steel, Ltd.
    Inventors: Yosuke Matsumoto, Atsushi Inada, Masamichi Chiba
  • Patent number: 9689050
    Abstract: A rolled steel sheet or blank is provided, the composition of which comprises the elements listed below in percent by weight: C?0.1%; 0.5%?Mn?7%; 0.5%?Si?3.5%; 0.5%<Ti?2%; 2%<Ni?7%; Al?0.10%; Cr?2%; Cu?2%; Co?2%; Mo?2%; S?0.005%; P?0.03%; Nb?0.1%; V?0.1%; B<0.005%; N?0.008%, and the silicon and titanium contents are such that: Si + Ti ? 2.5 ? % , Ti Si ? 0.3 the remainder of the composition consisting of iron and unavoidable impurities resulting from processing. A method for the fabrication of a part for a land motor vehicle from the sheet or blank by hot stamping is also provided. The microstructure of the part consisting essentially of martensite and intermetallic precipitates of type Fe2TiSi with an area percentage between 1 and 5% intermetallic precipitates.
    Type: Grant
    Filed: September 6, 2011
    Date of Patent: June 27, 2017
    Assignee: ARCELORMITTAL INVESTIGACIÓN Y DESARROLLO S.L.
    Inventors: Olivier Bouaziz, David Barbier, Coralie Jung
  • Patent number: 9689061
    Abstract: A tool steel, in particular a hot-work steel, has the following composition: 0.26 to 0.55% by weight C; less than 2% by weight Cr; 0 to 10% by weight Mo; 0 to 15% by weight W; wherein the W and Mo contents in total amount to 1.8 to 15% by weight; carbide-forming elements Ti, Zr, Hf, Nb, Ta forming a content of from 0 to 3% by weight individually or in total; 0 to 4% by weight V; 0 to 6% by weight Co; 0 to 1.6% by weight Si; 0 to 2% by weight Mn; 0 to 2.99% by weight Ni; 0 to 1% by weight S; remainder: iron and inevitable impurities. The hot-work steel has a significantly higher thermal conductivity than known tool steels.
    Type: Grant
    Filed: September 26, 2013
    Date of Patent: June 27, 2017
    Assignee: Rovalma, S.A.
    Inventor: Isaac Valls Angles