Next To Fe-base Component (e.g., Galvanized) Patents (Class 428/659)
  • Patent number: 11408046
    Abstract: High strength steel sheet having a tensile strength of 800 MPa or more comprising a middle part in sheet thickness and a soft surface layer arranged at one side or both sides of the middle part in sheet thickness, wherein each soft surface layer has a thickness of more than 10 ?M and 30% or less of the sheet thickness, the soft surface layer has an average Vickers hardness of more than 0.60 time and 0.90 time or less the average Vickers hardness of the sheet thickness 1/2 position, and the soft surface layer has a nano-hardness standard deviation of 0.8 or less is provided.
    Type: Grant
    Filed: February 20, 2018
    Date of Patent: August 9, 2022
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Yuya Suzuki, Katsuya Nakano, Genki Abukawa, Kunio Hayashi
  • Patent number: 11408059
    Abstract: A high-strength galvanized steel sheet includes a steel sheet having a steel composition having a specific component composition, a steel structure containing martensite and bainite at more than or equal to 70% (including 100%), ferrite at less than 20% (including 0%), and retained austenite at less than 5% (including 0%) in terms of area ratio, the amount of diffusible hydrogen in steel being less than or equal to 0.20 mass ppm; and a galvanizing layer provided on a surface of the steel sheet, having a content amount of Fe of 8 to 15% in mass %, and having an coating weight per one surface of 20 to 120 g/m2, wherein the amount of Mn oxides contained in the galvanizing layer is less than or equal to 0.050 g/m2, and a tensile strength is more than or equal to 1100 MPa and a yield ratio is more than or equal to 0.85.
    Type: Grant
    Filed: August 20, 2018
    Date of Patent: August 9, 2022
    Assignee: JFE STEEL CORPORATION
    Inventors: Hiromi Yoshitomi, Yasuaki Okita, Masaki Koba, Yoshihiko Ono, Hiroshi Matsuda
  • Patent number: 11396691
    Abstract: Provided is an alloy-plated steel material that can be used in home appliances, automobiles, and construction materials and the like and, more particularly, to an alloy-plated steel material having excellent corrosion resistance and high surface quality.
    Type: Grant
    Filed: December 22, 2017
    Date of Patent: July 26, 2022
    Assignee: POSCO
    Inventors: Il-Ryoung Sohn, Jong-Sang Kim, Tae-Chul Kim, Jung-Kuk Kim
  • Patent number: 11390932
    Abstract: A high-strength hot-dip galvanized steel sheet has a hot-dip galvanized layer on a surface of the steel sheet, a specific component composition, and a steel microstructure containing, on an area percentage basis, 0% to 15% of ferrite and upper bainite in total, 80% to 100% of lower bainite and martensite in total, and 0% to 10% of retained austenite, and containing precipitates having a particle size of 100 to 2,000 nm in an amount of 109 to 1012 particles/m2 in a region extending to a position 100 to 300 ?m from the surface layer of the steel sheet, in which the ratio of the average amount of C at a position 5 ?m from the surface layer of the steel sheet to the average amount of C at a position 70 ?m from the surface layer of the steel sheet in the thickness direction is 0.20 to 0.80.
    Type: Grant
    Filed: August 23, 2019
    Date of Patent: July 19, 2022
    Assignee: JFE STEEL CORPORATION
    Inventors: Hiroshi Hasegawa, Tatsuya Nakagaito
  • Patent number: 11390929
    Abstract: A method for manufacturing a hot-stamped part includes reheating a steel slab at a temperature of 1,200° C. to 1,250° C., the steel slab including, by wt %, 0.20 to 0.50% carbon (C), 0.05 to 1.00% silicon (Si), 0.10 to 2.50% manganese (Mn), more than 0% and not more than 0.015% phosphorus (P), more than 0% and not more than 0.005% sulfur (S), 0.05 to 1.00% chromium (Cr), 0.001 to 0.009% boron (B), 0.01 to 0.09% titanium (Ti), and a balance of iron (Fe) and inevitable impurities; finish-rolling the reheated steel slab at a temperature of 880° C. to 950° C.; cooling the hot-rolled steel plate without using water, and coiling the cooled steel plate at a temperature of 680° C. to 800° C. to form a hot-rolled decarburized layer on a surface of the steel plate; pickling the coiled steel plate, followed by cold rolling; annealing the cold-rolled steel plate in a reducing atmosphere; plating the annealed steel plate; and hot-stamping the plated steel plate.
    Type: Grant
    Filed: December 29, 2017
    Date of Patent: July 19, 2022
    Assignee: Hyundai Steel Company
    Inventors: Byung Gil Yoo, Hyeong Hyeop Do, Chee Woong Song, Hee Joong Lim, Sung Yul Huh
  • Patent number: 11384407
    Abstract: Provided are a high-strength galvannealed steel sheet, and a manufacturing method therefor. The manufacturing method is for a high-strength galvannealed steel sheet which includes a zinc coated layer with a coating weight of 20 to 120 g/m2 per side on a surface of a steel sheet having a chemical composition containing, in mass %, C: 0.03 to 0.35%, Si: 0.01 to 1.00%, Mn: 3.6 to 8.0%, Al: 0.001 to 1.00%, P: 0.100% or less, and S: 0.010% or less, with the balance being Fe and inevitable impurities. The method includes: setting a cold rolling reduction ratio to 20% or more and 35% or less when cold rolling is performed on the steel sheet, and setting a maximum steel sheet temperature to be reached in an annealing furnace to 600° C. or higher and 700° C. or lower when annealing is further performed on the steel sheet.
    Type: Grant
    Filed: June 5, 2017
    Date of Patent: July 12, 2022
    Assignee: JFE STEEL CORPORATION
    Inventors: Satoshi Maeda, Yoichi Makimizu, Yoshitsugu Suzuki, Yoshiyasu Kawasaki
  • Patent number: 11377709
    Abstract: Disclosed is a hot-pressed member that can exhibit very high tensile strength after hot pressing, excellent delayed fracture resistance, and high tensile shear stress after resistance spot welding by properly adjusting its chemical composition and its microstructure such that at least 20 Nb-based precipitates having a grain size of less than 0.10 ?m are present on average per 100 ?m2 of a cross section parallel to a thickness direction of the member, a prior austenite average grain size is 8 ?m or less, an average aspect ratio of prior austenite grains is 2.5 or less, and a volume fraction of martensite is 90% or more, and such that a standard deviation of Vickers hardness measured every 200 ?m on a surface of the member is 40 or less.
    Type: Grant
    Filed: March 30, 2018
    Date of Patent: July 5, 2022
    Assignee: JFE STEEL CORPORATION
    Inventors: Katsutoshi Takashima, Takashi Kobayashi, Yoshimasa Funakawa, Seiji Nakajima
  • Patent number: 11332816
    Abstract: Provided is a plated steel material which can be used for an automobile, a household appliance, a building material, and the like and, more specifically, to a zinc alloy plated steel material having excellent surface quality and corrosion resistance, and a method for manufacturing the same.
    Type: Grant
    Filed: December 13, 2018
    Date of Patent: May 17, 2022
    Assignee: POSCO
    Inventors: Il-Ryoung Sohn, Tae-Chul Kim, Jung-Kuk Kim, Kyung-Jin An, Jung-Hoon Kim, Jong-Un Jung, Jin-Seo Park
  • Patent number: 11332803
    Abstract: A high-strength hot-dip galvanized steel sheet contains predetermined amounts of C, Si, Mn, P, S, N, O, sol. Al, Ti, and B, 0.1 to 1.5 mass % of Cr+2×Mo, and a balance in a form of Fe and inevitable impurities. A steel structure includes, in area %, ferrite: 1 to 50%, martensite: 20 to 70%, residual austenite: 0 to 5%, pearlite: 0 to 5%, MA and cementite having 0.2 ?m or more grain size: 0 to 5% in total, and a balance in a form of bainite. A number density of MA or cementite having 0.2 ?m or more grain size and isolated in ferrite or bainite grains is 100 pcs/1000 ?m2 or less, and an average hardness of martensite is in a range from 330 to 500 Hv.
    Type: Grant
    Filed: March 22, 2018
    Date of Patent: May 17, 2022
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Takafumi Yokoyama, Yuji Yamaguchi, Masahiro Nakata, Kunio Hayashi, Satoshi Uchida, Takuma Kawanaka
  • Patent number: 11319607
    Abstract: Disclosed are a high-strength and high-toughness steel plate with an 800 MPa grade tensile strength and a method for manufacturing the same, the chemical composition of the steel plate in weight percentage being: C: 0.15-0.25%, Si: 1.0-2.0%, Mn: 1.2-2.0%, P?0.015%, S?0.005%, Al: 0.5-1.0%, N: ?0.006%, Nb: 0.02-0.06%, O?0.003%, and the balance being Fe and other inevitable impurities, and 1.5%?Si+Al?2.5%. By adopting an isothermal heat treatment a high-strength and high-toughness steel plate with an 800 MPa grade tensile strength, which has a microstructure mainly including bainite ferrite and residual austenite, is obtained impact energy.
    Type: Grant
    Filed: November 24, 2015
    Date of Patent: May 3, 2022
    Assignee: BAOSHAN IRON & STEEL CO., LTD.
    Inventors: Huanrong Wang, Ana Yang, Wei Wang
  • Patent number: 11319620
    Abstract: A martensitic steel alloy is provided. The martensitic steel alloy includes carbon from 0.22 to 0.36 wt. %, manganese from 0.5% to 2.0% wt. %, and chromium in an amount less than 0.10 wt. %. and a carbon equivalent Ceq of less than 0.44 in which Ceq=C+Mn/6+(Cr+Mo+V)/5+(Ni+Cu)/15. Ceq is the carbon equivalent, C, Mn, Cr, Mo, V, Ni, and Cu are in wt. % of the elements in the alloy. The alloy has an ultimate tensile strength of at least 1700 MPa.
    Type: Grant
    Filed: September 13, 2019
    Date of Patent: May 3, 2022
    Assignee: ArcelorMittal
    Inventors: Rongjie Song, Narayan S. Pottore
  • Patent number: 11306382
    Abstract: A Zn—Al—Mg coating on a steel strip. Specific amounts of Mg and Al are chosen, in a relationship wherein the amount of Al is higher than the amount of Mg. Also provided is a method for providing a steel strip having a Zn—Al—Mg coating provided by hot dip coating with a coating bath, wherein the thickness of the coating is controlled using gas knifes above the coating bath.
    Type: Grant
    Filed: July 20, 2017
    Date of Patent: April 19, 2022
    Assignee: TATA STEEL IJMUIDEN B.V.
    Inventors: Jaap Peter Van Eenennaam, Shangping Chen, Edgar Matthijs Toose
  • Patent number: 11279984
    Abstract: A cold rolled steel sheet, the steel containing, in weight percentage, 0.19%?carbon?0.24%, 1.9%?manganese?2.2%, 1.4%?silicon?1.6%, 0.01%?aluminum?0.06%, 0.2%?chromium?0.5%, phosphorus?0.02%, sulfur?0.003%, the balance including iron and unavoidable impurities, the steel sheet having a microstructure containing 5% to 15% of tempered martensite, 10% to 15% of residual austenite, the balance containing bainite, bainite content being at least 70%, is described. Also described is a manufacturing method and with use of such grade for making vehicle parts.
    Type: Grant
    Filed: December 19, 2017
    Date of Patent: March 22, 2022
    Assignee: ArcelorMittal
    Inventors: Jean-Marc Pipard, Marc Olivier Thenot, Pierre Targy
  • Patent number: 11255006
    Abstract: A steel alloy workpiece and a method for making a press-hardened steel (PHS) component using the steel alloy workpiece is provided. The steel alloy workpiece includes between about 1.0 and 5.0 weight percent chromium, between about 0.5 and 2.0 weight percent silicon, and a surface having a predetermined imprinted pattern. The imprinted pattern includes one of a plurality of overlapping nested sinusoidal waves and a honey-comb pattern, and ascribes a surface roughness of between about 1.0 microns and 2.5 microns. The method includes providing the steel alloy workpiece, heating the workpieces at a predetermined time and temperature, hot stamping the workpieces into the PHS component, quenching the PHS component at a predetermined quench rate, and e-coating the PHS component. The e-coating is applied directly onto the surface of the PHS component.
    Type: Grant
    Filed: July 11, 2019
    Date of Patent: February 22, 2022
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Qi Lu, Yang Guo
  • Patent number: 11248287
    Abstract: Zn alloy plated steel material having excellent weldability and processed-part corrosion resistance and a method for production of Zn alloy plated steel material are provided. In the Zn alloy plated steel material comprising base steel material and a Zn alloy plating layer, the Zn alloy plating layer includes, by wt %, Al: 0.1-5.0%, Mg: 0.1-5.0%, as well as a remainder of Zn and inevitable impurities. The Zn alloy plated steel material includes a lower interface layer and an upper interface layer between the base steel material and the Zn alloy plating layer, wherein the lower interface layer is formed on the base steel material and has a dense structure, and the upper interface layer is formed on the lower interface layer and has a network-type or island-type structure.
    Type: Grant
    Filed: January 27, 2020
    Date of Patent: February 15, 2022
    Assignee: POSCO
    Inventors: Min-Suk Oh, Sang-Heon Kim, Tae-Chul Kim, Jong-Sang Kim, Hyun-Chu Yun, Bong-Hwan Yoo, Il-Ryoung Sohn
  • Patent number: 11236413
    Abstract: A coated metal sheet is provided. The coated metal sheet includes a steel substrate, a metal coating on at least one face of the steel substrate, the metal coating comprising at least 40% by weight of zinc; and a layer coating an outer surface of the metal coating, the layer including an amino acid in a neutral or salt form, the amino acid being selected from among alanine, arginine, aspartic acid, cysteine, glutamine, lysine, methionine, proline, serine, threonine, or of a mixture thereof, the amount of said amino acid or of said mixture being from 0.1 to 200 mg/m2, and optionally a base or a mixture of bases, or an acid or a mixture of acids.
    Type: Grant
    Filed: October 15, 2019
    Date of Patent: February 1, 2022
    Assignee: ARCELORMITTAL
    Inventors: Lydia Rachiele, Herve Derule, Delphine Thai
  • Patent number: 11214847
    Abstract: A high-strength hot-rolled steel sheet for an electric resistance welded steel pipe has decreased variations in in-plane material properties, high strength, and excellent ductility. The high-strength hot-rolled steel sheet has a composition containing, in mass %, C: 0.10 to 0.18%, Si: 0.1 to 0.5%, Mn: 0.8 to 2.0%, P: 0.001 to 0.020%, S: 0.005% or less, Al: 0.001 to 0.1%, Cr: 0.4 to 1.0%, Cu: 0.1 to 0.5%, Ni: 0.01 to 0.4%, Nb: 0.01 to 0.07%, N: 0.008% or less, and further Mo: 0.5% or less and/or V: 0.1% or less so that Moeq defined as Moeq=Mo+0.36Cr+0.77Mn+0.07Ni is 1.4 to 2.2, and Mo and V are contained to satisfy 0.05?Mo+V?0.5; and has a microstructure containing, in volume fraction, 80% or more of a bainite phase as a primary phase and 4 to 20% of a martensite phase and a retained austenite phase in total as a secondary phase, where the bainite phase has an average grain size of 1 to 10 ?m.
    Type: Grant
    Filed: January 23, 2017
    Date of Patent: January 4, 2022
    Assignee: JFE Steel Corporation
    Inventors: Hiroshi Nakata, Motohiko Urabe, Shuji Kawamura
  • Patent number: 11208705
    Abstract: A high-strength cold-rolled steel sheet which is a steel sheet having a tensile strength of 980 MPa or more has a predetermined chemical component composition, a metallographic microstructure of the steel sheet contains, by area ratio, ferrite and granular bainite: 10% or more and 50% or less in total, one or both of upper bainite and lower bainite: 10% or more and 50% or less in total, tempered martensite: more than 0% and 30% or less, retained austenite: 5% or more, and one or more of pearlite, cementite, and martensite: 0% to 10% in total, and an area ratio of the ferrite with respect to a total area ratio of the ferrite and the granular bainite is 25% or less.
    Type: Grant
    Filed: November 15, 2017
    Date of Patent: December 28, 2021
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Yuri Toda, Kunio Hayashi, Katsuya Nakano, Eisaku Sakurada, Akihiro Uenishi, Kengo Takeda
  • Patent number: 11208702
    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: January 31, 2019
    Date of Patent: December 28, 2021
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Akifumi Sakakibara, Tatsuo Yokoi, Hiroshi Shuto, Yuuki Kanzawa, Masafumi Azuma
  • Patent number: 11203807
    Abstract: A coating for a carrier material made of a steel material for joining to an aluminum material includes a first sublayer on the core part side and a second sublayer on the outside. On average, the coating includes approximately 1 to 10 wt. % silicon and iron, the remainder being aluminum. The first sublayer at least approximately includes 42 wt. % iron, 11 wt. % silicon, and no more than approximately 45 wt. % aluminum, which constitutes the remainder, and has a thickness of no more than approximately 3.5 ?m. The second sublayer includes approximately 1 to 10 wt. % silicon, the remainder being aluminum, and has a thickness of approximately 5 to approximately 95 ?m.
    Type: Grant
    Filed: November 23, 2017
    Date of Patent: December 21, 2021
    Assignee: Universität Siegen
    Inventor: Xiangfan Fang
  • Patent number: 11193180
    Abstract: A high-strength steel sheet having a chemical composition containing, by mass %, C: 0.15% to 0.25%, Si: 1.00% to 2.20%, Mn: 2.00% to 3.50%, P: 0.05% or less, S: 0.005% or less, Al: 0.01% to 0.50%, N: 0.010% or less, B: 0.0003% to 0.0050%, one, two, or more selected from Ti: 0.005% to 0.05%, Cu: 0.003% to 0.50%, Ni: 0.003% to 0.50%, Sn: 0.003% to 0.50%, Co: 0.003% to 0.05%, and Mo: 0.003% to 0.50%, and the balance being Fe and inevitable impurities and a microstructure including, in terms of volume fraction, 15% or less (including 0%) of ferrite, 2% to 15% of retained austenite, 10% or less (including 0%) of martensite, and the balance being bainite and tempered martensite, in which the average number of cementite grains having a grain diameter of 0.04 ?m or more existing in the bainite and tempered martensite grains is 10 or more.
    Type: Grant
    Filed: March 22, 2017
    Date of Patent: December 7, 2021
    Assignee: JFE STEEL CORPORATION
    Inventors: Katsutoshi Takashima, Yoshimasa Funakawa, Takashi Kobayashi
  • Patent number: 11180822
    Abstract: Disclosed is provided a low yield ratio and superhigh-strength hot-rolled Q&P steel and a method for manufacturing the same, having the following chemical composition in weight percentage: C: 0.2-0.3%, Si: 1.0-2.0%, Mn: 1.5-2.5%, P: ?0.015%, S: ?0.005%, Al: 0.5-1.0%, N: ?0.006%, Nb: 0.02-0.06%, Ti: ?0.03%, O: ?0.003%, and the balance being Fe and inevitable impurities. The manufacture method comprises a stepped cooling process to finally obtain the steel with a three-phase structure containing a certain volume fraction of proeutectoid ferrite; martensite; and residual austenite, and having an excellent comprehensive performance with a yield strength of ?600 MPa, a tensile strength of ?1300 MPa, a good elongation, and a low yield ratio. The obtained Q&P steel also shows an excellent match of high plasticity suitable for easy deformabilities and wear-resistances.
    Type: Grant
    Filed: November 24, 2015
    Date of Patent: November 23, 2021
    Assignee: BAOSHAN IRON & STEEL CO., LTD.
    Inventors: Huanrong Wang, Ana Yang, Wei Wang
  • Patent number: 11124853
    Abstract: A method for producing a cold rolled steel sheet having a tensile strength ?1470 MPa and a total elongation TE?19%, the method comprising the steps of annealing at an annealing temperature AT?Ac3 a non-treated steel sheet whose chemical composition contains in weight %: 0.34%?C?0.40%, 1.50%?Mn?2.30%, 1.50?Si?2.40%, 0<Cr?0.5%, 0<Mo?0.3%, 0.01%?Al?0.07%, the remainder being Fe and unavoidable impurities, quenching the annealed steel sheet by cooling it to a quenching temperature QT<Ms transformation point and between 150° C. and 250° C., and making a partitioning treatment by reheating the quenched steel sheet to a partitioning temperature PT between 350° C. and 420° C. and maintaining the steel sheet at this temperature during a partitioning time Pt between 15 seconds and 120 seconds.
    Type: Grant
    Filed: May 15, 2019
    Date of Patent: September 21, 2021
    Assignee: ARCELORMITTAL
    Inventors: Olga A. Girina, Damon Panahi
  • Patent number: 11111567
    Abstract: A non-oriented electrical steel sheet including, as a chemical composition, by mass %: C: 0.0030 % or less; Si: 2.00 % to 4.00 %; Al: 0.01 % to 3.00 %; Mn: 0.10 % to 2.00 %; P: 0.005 % to 0.200 %; S: 0.0030 % or less; Cu: more than 1.0 % and 3.0 % or less; Ni: 0.10 % to 3.0 %; one or more coarse precipitate forming element: more than 0.0005 % and 0.0100 % or less in total; a parameter Q (Q=[Si] +2 [Al] [Mn]) is 2.00 or more; Sn: 0.00 % to 0.40 %; Cr: 0.0 % to 10.0 %, and a remainder: Fe and impurities, wherein a number of Cu particles having a diameter of less than 100 nm is 5 or more per 10 ?m2, a {100} crystal orientation intensity is 2.4 or more, a thickness is 0.10 mm to 0.60 mm, and an average grain size is 70 ?m to 200 ?m.
    Type: Grant
    Filed: March 25, 2019
    Date of Patent: September 7, 2021
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Tesshu Murakawa, Hiroshi Fujimura, Satoshi Kano
  • Patent number: 11085100
    Abstract: A high strength steel sheet having a high Young's modulus, the steel sheet having a chemical composition including, by mass %, C: 0.060% or more and 0.150% or less, Si: 0.50% or more and 2.20% or less, Mn: 1.00% or more and 3.00% or less, and one or both of Ti: 0.001% or more and 0.200% or less and Nb: 0.001% or more and 0.200% or less, in which the contents of C, N, S, Ti, and Nb satisfy the equation 500?C*?1300. The steel sheet has a microstructure including ferrite in an amount of 20% or more and martensite in an amount of 5% or more, in terms of area ratio, such that the average grain size of the ferrite is 20.0 ?m or less and the inverse intensity ratio of ?-fiber for ?-fiber is 1.00 or more in the ferrite and the martensite.
    Type: Grant
    Filed: June 26, 2019
    Date of Patent: August 10, 2021
    Assignee: JFE STEEL CORPORATION
    Inventors: Hidekazu Minami, Takeshi Yokota, Kazuhiro Seto
  • Patent number: 11078552
    Abstract: A high-strength steel sheet exhibiting excellent ductility and stretch-flangeability, and a method for manufacturing such a high-strength steel sheet. The high-strength steel sheet has a chemical composition including specific proportions of components in which C/Mn is 0.08 to 0.20, the balance being iron and inevitable impurities, and includes microstructures including, in terms of area fraction relative to all the microstructures, 40% to 70% total of ferrite and bainitic ferrite, 5% to 35% martensite and 5% to 30% retained austenite. The proportion of martensite (including retained austenite) adjacent to bainitic ferrite is not less than 60% of all martensite (including retained austenite). The proportion of 4.0 GPa and smaller differences in microhardness measured at 0.5 ?m intervals is not less than 70%. The proportion of microstructures with 8.0 GPa or smaller microhardness is not less than 85% of all the microstructures.
    Type: Grant
    Filed: January 30, 2017
    Date of Patent: August 3, 2021
    Assignee: JFE STEEL CORPORATION
    Inventors: Fusae Shiimori, Shinjiro Kaneko, Yasunobu Nagataki
  • Patent number: 11077522
    Abstract: A method of laser spot welding a workpiece stack-up that includes at least two overlapping steel workpieces, at least one of which includes a surface coating, is disclosed. The method includes directing a laser beam at the top surface of the workpiece stack-up to create a molten steel weld pool that penetrates into the stack-up. The molten steel weld pool is then grown to penetrate further into the stack-up by increasing an irradiance of the laser beam while reducing the projected sectional area of the laser beam at a plane of the top surface of the workpiece stack-up. Increasing the irradiance of the laser beam may be accomplished by moving a focal point of the laser beam closer to the top surface or by reducing an angle of incidence of the laser beam so as to reduce the eccentricity of the projected sectional area of the laser beam.
    Type: Grant
    Filed: January 18, 2016
    Date of Patent: August 3, 2021
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: David Yang, Wu Tao, Li Sun
  • Patent number: 11078590
    Abstract: A plated steel includes: a steel; a zinc based electroplated layer formed on a surface of the steel; and an organic resin coating layer formed on a surface of the zinc based electroplated layer, in which the surface of the zinc based electroplated layer has hairline extending in a predetermined direction, Ra (ML) measured on the surface of the zinc based electroplated layer is 0.10 to 0.70 ?m, on the surface of the zinc based electroplated layer, a peak number PPI measured in a hairline orthogonal direction with a reference level of 10 ?inch satisfies PPI?350×Ra (MC) with respect to Ra (MC), on a surface of the organic resin coating layer, Ra (CC) satisfies Ra (CC)/Ra (CL)?1.10 with respect to Ra (CL), and Ra (CC) satisfies Ra (CC)<Ra (MC) with respect to Ra (MC).
    Type: Grant
    Filed: June 15, 2018
    Date of Patent: August 3, 2021
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Takashi Futaba, Kiyokazu Ishizuka, Fumio Shibao, Ikuo Kikuchi, Hidetoshi Shindo, Hiroaki Uramoto, Keita Katsumaru
  • Patent number: 11078586
    Abstract: This zinc-nickel composite plating bath contains a zinc source, a nickel source, silicon dioxide particles and an ammonium-based dispersant in such ranges that enable the achievement of a zinc-nickel composite plating film wherein the codeposition amount of nickel is 10-16 wt % and the codeposition amount of the silicon dioxide particles is 7 vol % or more. Meanwhile, the pH of this zinc-nickel composite plating bath is 5.6 to 6.8.
    Type: Grant
    Filed: September 13, 2017
    Date of Patent: August 3, 2021
    Assignee: HONDA MOTOR CO., LTD.
    Inventors: Yuki Furukawa, Yoshimitsu Ogawa, Masahiro Yamanaka
  • Patent number: 11078564
    Abstract: Provided is a hot-dip galvanized steel sheet including a base steel sheet and a hot-dip zinc-based plating layer formed on the base steel sheet. The hot-dip zinc-based plating layer includes a Zn single phase having an average equivalent circular diameter of 120 ?m or less as a microstructure. In the Zn single phase, a Zn single phase having a crystal structure of which a {0001} plane is parallel to a surface of the steel sheet, is provided in an area fraction of 70% or less.
    Type: Grant
    Filed: December 22, 2016
    Date of Patent: August 3, 2021
    Assignee: POSCO
    Inventor: Sang-Heon Kim
  • Patent number: 11066721
    Abstract: A high-strength hot-dip coated hot-rolled steel sheet excellent in terms of surface appearance quality and coating adhesiveness and a method for manufacturing. The method includes performing hot rolling followed by pickling on steel to form a pickled steel sheet, the steel having a chemical composition containing, by mass %, C: 0.02% or more and 0.30% or less, Si: 0.01% or more and 1.0% or less, Mn: 0.3% or more and 2.5% or less, P: 0.08% or less, S: 0.02% or less, Al: 0.001% or more and 0.20% or less, and Fe and inevitable impurities. The method further includes performing rolling with a rolling reduction ratio of 1% or more and 10% or less, and a hot-dip coating treatment. The obtained steel sheet has an arithmetic average roughness Ra of 2.0 ?m or less on the surface of the steel sheet, and a tensile strength of 590 MPa or more.
    Type: Grant
    Filed: November 8, 2016
    Date of Patent: July 20, 2021
    Assignee: JFE STEEL CORPORATION
    Inventors: Masaki Koba, Yoshitsugu Suzuki, Hiroyuki Masuoka
  • Patent number: 11035019
    Abstract: A steel sheet has a microstructure that contains ferrite in an area ratio of 20% or more, martensite in an area ratio of 5% or more, and tempered martensite in an area ratio of 5% or more. The ferrite has a mean grain size of 20.0 ?m or less. An inverse intensity ratio of ?-fiber to ?-fiber in the ferrite is 1.00 or more and an inverse intensity ratio of ?-fiber to ?-fiber in the martensite and the tempered martensite is 1.00 or more.
    Type: Grant
    Filed: January 27, 2016
    Date of Patent: June 15, 2021
    Assignee: JFE STEEL CORPORATION
    Inventors: Hidekazu Minami, Shinjiro Kaneko, Takeshi Yokota, Kazuhiro Seto
  • Patent number: 11001918
    Abstract: Provided is a method of manufacturing a hot-dip galvanized steel sheet. According to an aspect of the present invention, the method may include preparing a base steel sheet, forming a iron (Fe)-plated layer on the prepared base steel sheet, oxidation heating the steel sheet having the Fe-plated layer formed thereon at a temperature ranging from 600° C. to 800° C., maintaining the heated steel sheet at a temperature ranging from 750° C. to 900° C. for 5 seconds or more in a reducing atmosphere with a dew point of between ?30° C. to 5° C. including 20 ppm or less of oxygen, 1 vol % to 20 vol % of H2, and N2 as well as unavoidable gases as a remainder, cooling the maintained steel sheet, and plating the cooled steel sheet by dipping in a hot-dip galvanizing bath.
    Type: Grant
    Filed: December 22, 2017
    Date of Patent: May 11, 2021
    Assignee: POSCO
    Inventors: Myung-Soo Kim, Jong-Sang Kim, Young-Ha Kim, Joong-Chul Park
  • Patent number: 10988853
    Abstract: Stainless steel sheets including a Ni and O-containing coating on the surface that has excellent weld penetration characteristics and excellent crevice corrosion resistance, and a method for producing such stainless steel sheets. A stainless steel sheet includes a Ni and O-containing coating on a surface of the stainless steel sheet. The Ni and O-containing coating has a coating weight of greater than or equal to 0.1 g/m2 and less than or equal to 20 g/m2. The Ni and O-containing coating has a composition including, in at. %, Ni: greater than or equal to 25% and less than or equal to 60%, and O: greater than or equal to 40% and less than or equal to 70%.
    Type: Grant
    Filed: January 5, 2017
    Date of Patent: April 27, 2021
    Assignee: JFE STEEL CORPORATION
    Inventors: Junichiro Hirasawa, Shin Ishikawa, Chikara Kami, Shinji Ootsuka
  • Patent number: 10975454
    Abstract: Provided is an ultra-high strength steel sheet having excellent phosphatability and bendability. The ultra-high strength steel sheet includes, by weight percentage (wt %), carbon (C): 0.08% to 0.2%, silicon (Si): 0.05% to 1.3%, manganese (Mn): 2.0% to 3.0%, phosphorus (P): 0.001% to 0.10%, sulfur (S): 0.010% or less, aluminum (Al): 0.01% to 0.1%, chromium (Cr): 0.3% to 1.2%, boron (B): 0.0010% to 0.0030%, titanium (Ti): 0.01% to 0.05%, nitrogen (N): 0.001% to 0.01%, a remainder of iron (Fe) and other inevitable impurities, satisfying: 3.4?Ti/N?10, 1.0?Mn/(Si+Cr), and 0.7?Mn*/(Si*+Cr*)?Mn/(Si+Cr), where Ti, N, Mn, Si and Cr refer to a weight percentage (wt %), and Mn*, Si* and Cr* refer to an average of values obtained by GDS component analysis from a surface to a 0.1 ?m position in a thickness direction.
    Type: Grant
    Filed: December 7, 2016
    Date of Patent: April 13, 2021
    Assignee: POSCO
    Inventor: Seok-Jong Seo
  • Patent number: 10968502
    Abstract: A cold-rolled ultra-high strength, multi-phase structured steel is disclosed with improved stamping and forming performance during manufacturing processes, while possessing one or more of the following properties: excellent castability and rollability, excellent galvanizability and/or coatability, excellent formability, excellent fracture resistance, excellent stretch formability and stretch flangeability, excellent dent resistance, excellent durability, excellent impact performance and structural performance, excellent intrusion and crash resistance, and excellent weldability, without the purposeful addition of boron.
    Type: Grant
    Filed: November 3, 2017
    Date of Patent: April 6, 2021
    Assignee: NUCOR CORPORATION
    Inventor: Weiping Sun
  • Patent number: 10953631
    Abstract: There is provided a hot-dip galvanized steel sheet with a microstructure in a ? thickness to ? thickness range whose middle is a ¼ thickness from a surface of a base steel sheet, the microstructure contains ferrite phase is 50% or more and 97% or less by volume fraction, and a predetermined phase wherein at an interface between a hot-dip galvanizing layer and the base steel sheet, a Fe—Al alloy layer has an average thickness of 0.1 ?m to 2.0 ?m, and a difference between a maximum thickness and a minimum thickness in a steel sheet width direction is within 0.5 ?m, and in a fine-grain layer directly brought into contact with the Fe—Al alloy layer, the fine-grain has a difference between a maximum thickness and a minimum thickness of the fine-grain layer in the steel sheet width direction is within 2.0 ?m.
    Type: Grant
    Filed: July 31, 2017
    Date of Patent: March 23, 2021
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Atsushi Morishita, Taihei Kaneto, Satoshi Uchida, Tatsuya Nakada, Yuji Yamaguchi
  • Patent number: 10934600
    Abstract: A steel sheet has a microstructure that contains ferrite in an area ratio of 20% or more, martensite in an area ratio of 5% or more, and tempered martensite in an area ratio of 5% or more. The ferrite has a mean grain size of 20.0 ?m or less. An inverse intensity ratio of ?-fiber to ?-fiber in the ferrite is 1.00 or more and an inverse intensity ratio of ?-fiber to ?-fiber in the martensite and the tempered martensite is 1.00 or more.
    Type: Grant
    Filed: January 27, 2016
    Date of Patent: March 2, 2021
    Assignee: JFE STEEL CORPORATION
    Inventors: Hidekazu Minami, Shinjiro Kaneko, Takeshi Yokota, Kazuhiro Seto
  • Patent number: 10920293
    Abstract: Provided herein is a plated steel having high strength with excellent elongation, excellent hole expansibility, and excellent material uniformity, and a method for producing such a plated steel. The steel sheet provided herein has a specific composition, and a steel structure that contains ferrite as a primary phase, and 2 to 12% of perlite, and 3% or less of martensite by volume, and in which the remainder is a low-temperature occurring phase. The ferrite has an average crystal grain diameter of 25 ?m or less. The perlite has an average crystal grain diameter of 5 ?m or less. The martensite has an average crystal grain diameter of 1.5 ?m or less. The perlite has a mean free path of 5.5 ?m or more. The steel sheet has a tensile strength of 440 MPa or more.
    Type: Grant
    Filed: March 21, 2017
    Date of Patent: February 16, 2021
    Assignee: JFE Steel Corporation
    Inventors: Katsutoshi Takashima, Yoshimasa Funakawa
  • Patent number: 10920294
    Abstract: A steel sheet having low yield ratio, tensile strength of 780 MPa or more, and good bending fatigue properties. The steel sheet includes a specific chemical composition and a steel microstructure having an area percentage of a ferrite phase of 20% or more and 80% or less and an area percentage of a martensite phase of 20% or more and 80% or less, the area percentage being determined by microstructure observation, in which a surface layer portion of the steel sheet has an average ferrite grain size of 5.0 ?m or less and an inclusion density of 200 particles/mm?2 or less, and in which the steel sheet has a surface hardness of 95% or more when the steel sheet has a hardness of 100% at a position ½t, where t represents the thickness of the steel sheet, away from a surface of the steel sheet in the thickness direction.
    Type: Grant
    Filed: March 17, 2017
    Date of Patent: February 16, 2021
    Assignee: JFE STEEL CORPORATION
    Inventors: Noriaki Kohsaka, Yoshimasa Funakawa
  • Patent number: 10907236
    Abstract: A steel sheet for a drawn can has a predetermined chemical composition and has a ferrite single-phase structure with a crystal grain size number of 11.0 or more, the sheet thickness is 0.15 to 0.50 mm, in an L direction of the steel sheet after an ageing treatment at 100° C. for one hour, an yield strength YP is 220 to 290 MPa, a tensile strength TS is 330 to 390 MPa, a total elongation EL is 32% or more, an yield point elongation YP-EL is 0%, an average plastic strain ratio rm is more than 1.35, and an in-plane anisotropy ?r is ?0.30 to +0.15.
    Type: Grant
    Filed: April 19, 2018
    Date of Patent: February 2, 2021
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Masaharu Oka, Nobusato Kojima, Yuta Dairokuno, Michihiro Nono
  • Patent number: 10907232
    Abstract: A method for producing a high strength coated steel sheet having an improved ductility and an improved formability, the chemical composition of the steel containing: 0.13%?C?0.22%, 1.9%?Si?2.3%, 2.4%?Mn?3%, Al?0.5%, Ti<0.05%, Nb<0.05%, the remainder being Fe and unavoidable impurities. The sheet is annealed at temperature TA higher than Ac3 but less than 1000° C. for a time of more than 30 s, quenched by cooling to a quenching temperature QT between 200° C. and 280° C. in order to obtain a structure consisting of austenite and at least 50% of martensite, the austenite content being such that the final structure can contain between 3% and 15% of residual austenite and between 85% and 97% of the sum of martensite and bainite, without ferrite, heated up to a partitioning temperature PT between 430° C. and 490° C. and maintained at this temperature for a time Pt between 10 s and 100 s, hot dip coated and cooled to the room temperature.
    Type: Grant
    Filed: July 3, 2015
    Date of Patent: February 2, 2021
    Assignee: ARCELORMITTAL
    Inventors: Dongwei Fan, Hyun Jo Jun, Rashmi Ranjan Mohanty, Pavan K. C. Venkatasurya
  • Patent number: 10907235
    Abstract: A steel sheet according to an aspect of the present invention has a chemical composition within a predetermined range; in which a metallographic structure at a thickness ¼ portion includes, by unit area %, ferrite: 10% or more and less than 50%, granular bainite: 5% or more and less than 50%, and martensite: 20% or more and less than 60%; in the metallographic structure at the thickness ¼ portion, a total of upper bainite, lower bainite, residual austenite, and pearlite is 0% or more and less than 15% by unit area %; at the thickness ¼ portion, a product of an area ratio Vm of the martensite and an average hardness Hv of the martensite is 12,000 to 34,000; and a tensile strength is 980 MPa or higher.
    Type: Grant
    Filed: September 13, 2016
    Date of Patent: February 2, 2021
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Yuri Toda, Kunio Hayashi, Katsuya Nakano, Hiroyuki Kawata, Akihiro Uenishi
  • Patent number: 10900096
    Abstract: Provided herein is a steel sheet of a specific composition that has a micro structure containing, by volume, 75 to 95% of ferrite, 3 to 15% of martensite, 0.5 to 10% of perlite, 10% or less of unrecrystallized ferrite, and 21.5% or less of a low-temperature occurring phase representing the remainder, and in which the ferrite has an average crystal grain diameter of 6 ?m or less, and the martensite has an average crystal grain diameter of 3 ?m or less, and an average aspect ratio of 4.0 or less, and in which a Nb base precipitate having an average grain diameter of 0.10 ?m or less is contained. The steel sheet has a tensile strength of 590 MPa or more.
    Type: Grant
    Filed: March 21, 2017
    Date of Patent: January 26, 2021
    Assignee: JFE STEEL CORPORATION
    Inventors: Katsutoshi Takashima, Chikaumi Sawanishi, Yoshimasa Funakawa
  • Patent number: 10889873
    Abstract: A high strength steel sheet mainly used as an automotive exterior panel material is provided. In detail, a complex-phase steel sheet having excellent formability and a method of manufacturing the same are provided. A steel sheet may have excellent strength and ductility, and a relatively low yield ratio and an excellent surface quality may be provided.
    Type: Grant
    Filed: March 7, 2017
    Date of Patent: January 12, 2021
    Assignee: POSCO
    Inventors: Yeon Sang An, Sang Ho Han
  • Patent number: 10822683
    Abstract: A hot-dip galvanized steel sheet includes a base steel sheet and a hot-dip galvanized layer formed on at least one surface of the base steel sheet, in which the hot-dip galvanized layer includes Fe in a content of more than 0% to 5% or less, Al in a content of more than 0% to 1.0% or less, and columnar grains formed by a ? phase on the surface of the steel sheet, further, 20% or more of the entire interface between the hot-dip galvanized layer and the base steel sheet is coated with the ? phase, and a ratio of an interface formed between ? grains in which coarse oxides are present among grains and the base steel sheet with respect to the entire interface between the ? phase and the base steel sheet in the hot-dip galvanized layer is 50% or less, the base steel sheet has predetermined chemical components and a refined layer in direct contact with the interface between the base steel sheet and the hot-dip galvanized layer, an average thickness of the refined layer is 0.1 to 5.
    Type: Grant
    Filed: November 5, 2015
    Date of Patent: November 3, 2020
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Hiroyuki Kawata, Takeshi Yasui, Kohei Ueda, Naoki Maruyama, Yuji Yamaguchi, Satoshi Uchida, Ryosuke Komami, Hayato Arai, Toyomitsu Nakamura
  • Patent number: 10822672
    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: Grant
    Filed: July 13, 2015
    Date of Patent: November 3, 2020
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Yuri Toda, Masafumi Azuma, Akihiro Uenishi, Hiroyuki Kawata, Naoki Maruyama, Genichi Shigesato
  • Patent number: 10822684
    Abstract: A hot-dip galvanized steel sheet includes a base steel sheet and a hot-dip galvanized layer formed on at least one surface of the base steel sheet, in which the hot-dip galvanized layer includes Fe in a content of more than 0% to 5% or less, Al in a content of more than 0% to 1.0% or less, and columnar grains formed by a ? phase on the surface of the steel sheet, further, 20% or more of the entire interface between the hot-dip galvanized layer and the base steel sheet is coated with the ? phase, and a ratio of an interface formed between ? grains in which coarse oxides are present among ? grains and the base steel sheet with respect to the entire interface between the ? phase and the base steel sheet in the hot-dip galvanized layer is 50% or less, the base steel sheet has predetermined chemical components and a refined layer in direct contact with the interface between the base steel sheet and the hot-dip galvanized layer, an average thickness of the refined layer is 0.1 to 5.
    Type: Grant
    Filed: November 5, 2015
    Date of Patent: November 3, 2020
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Hiroyuki Kawata, Takeshi Yasui, Kohei Ueda, Naoki Maruyama, Yuji Yamaguchi, Satoshi Uchida, Ryosuke Komami, Hayato Arai, Toyomitsu Nakamura
  • Patent number: 10815553
    Abstract: Provided is a galvannealed steel sheet having high strength and excellent deep drawability, and being further excellent in slab cracking resistance and secondary working embrittlement resistance. A base metal steel sheet of the galvannealed steel sheet has a chemical composition containing, in mass %: C: 0.0080% or less; Si: 0.7% or less; Mn: 1.0 to 2.5%; P: more than 0.030 to 0.048%; S: 0.025% or less; Al: 0.005 to 0.20%; N: 0.010% or less; Ti: 0.005 to 0.040%; Nb: 0.005 to 0.060%; and B: 0.0005 to 0.0030%, with the balance being Fe and impurities, satisfying Formula (1) to (4). A galvannealed layer contains 7 to 15 mass % of Fe. 25×P+4×Si?3.6??(1) B?X1?0.0005??(2) C?(12/93)×Nb?X2??0.
    Type: Grant
    Filed: August 22, 2016
    Date of Patent: October 27, 2020
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Masaharu Oka, Nobusato Kojima, Tetsuya Okada
  • Patent number: 10808291
    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: Grant
    Filed: July 13, 2015
    Date of Patent: October 20, 2020
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Yuri Toda, Masafumi Azuma, Akihiro Uenishi, Hiroyuki Kawata, Naoki Maruyama, Genichi Shigesato