Working Patents (Class 148/111)
  • Patent number: 11299791
    Abstract: A non-oriented electric steel sheet includes 2.5 wt % to 3.1 wt % of Si, 0.1 wt % to 1.3 wt % of Al, 0.2 wt % to 1.5 wt % of Mn, 0.008 wt % or less of C (excluding 0 wt %), 0.005 wt % or less of S (excluding 0 wt %), 0.005 wt % or less of N (excluding 0 wt %), 0.005 wt % or less of Ti (excluding 0 wt %), 0.001 wt % to 0.07 wt % of Mo, 0.001 wt % to 0.07 wt % of P, 0.001 wt % to 0.07 wt % of Sn, and 0.001 wt % to 0.07 wt % of Sb, in which a remainder includes Fe and inevitable impurities, an average crystal grain diameter is 70 ?m to 150 ?m, the non-oriented electric steel sheet satisfies Equations (1) and (2), 0.32?([Al]+[Mn])/[Si]?0.5??[Equation 1] 0.025?[Mo]+[P]+[Sn]+[Sb]?0.15??[Equation 2] (here, a bracket denotes the contents (wt %) of each element).
    Type: Grant
    Filed: December 9, 2016
    Date of Patent: April 12, 2022
    Assignee: POSCO
    Inventors: Hun Ju Lee, Yong Soo Kim, Su Yong Sin
  • Patent number: 11299792
    Abstract: A non-oriented electrical steel sheet according to an embodiment of the present invention includes Ti at 0.0030 wt % or less (excluding 0 wt %), Nb at 0.0035 wt % or less (excluding 0 wt %), V at 0.0040 wt % or less (excluding 0 wt %), B at 0.0003 wt % to 0.0020 wt %, and the remaining portion including Fe and other inevitably added impurities, wherein a value of ([Ti]+0.8[Nb]+0.5[V])/(10*[B]) may be 0.17 to 7.8.
    Type: Grant
    Filed: December 21, 2015
    Date of Patent: April 12, 2022
    Assignee: POSCO
    Inventors: Jae-Hoon Kim, Jong Uk Ryu, Seung Il Kim, Sin Young Jung, Su Yong Sin, Sang Woo Lee
  • Patent number: 11295881
    Abstract: A non-oriented electrical steel sheet has a predetermined chemical composition, and when an average value of Mn concentrations in a range from a surface of a base iron to a position where a depth from the surface of the base iron is 2 ?m is set to [Mn2], and an Mn concentration at a position where a depth from the surface of the base iron is 10 ?m is set to [Mn10], the base iron satisfies the following expression 1. 0.1?[Mn2]/[Mn10]?0.
    Type: Grant
    Filed: August 2, 2017
    Date of Patent: April 5, 2022
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Yoshiaki Natori, Hiroyoshi Yashiki, Masaru Takahashi, Kazutoshi Takeda, Takuya Matsumoto
  • Patent number: 11286538
    Abstract: In a grain-oriented electrical steel sheet which is manufactured from a thin slab without using an inhibitor forming component, excellent magnetic properties are stably achieved. In a method for manufacturing a grain-oriented electrical steel sheet, a slab heating and annealing are performed under specific conditions.
    Type: Grant
    Filed: February 19, 2018
    Date of Patent: March 29, 2022
    Assignee: JFE STEEL CORPORATION
    Inventors: Masanori Takenaka, Takeshi Imamura, Yuiko Ehashi, Hiroi Yamaguchi
  • Patent number: 11261513
    Abstract: A method of producing a strip from a CoFe alloy is provided. A slab consisting substantially of 35 wt %?Co?55 wt %, 0 wt %?V?3 wt %, 0 wt %?Ni?2 wt %, 0 wt %?Nb?0.50 wt %, 0 wt %?Zr+Ta?1.5 wt %, 0 wt %?Cr?3 wt %, 0 wt %?Si?3 wt %, 0 wt %?Al?1 wt %, 0 wt %?Mn?1 wt %, 0 wt %?B?0.25 wt %, 0 wt %?C?0.1 wt %, the remainder being Fe and up to 1 wt % of impurities, is hot rolled and then quenched from a temperature above 700° C. to less than 200° C. The hot rolled strip is cold rolled. The cold rolled strip is stationary annealed to produce an intermediate strip, and the intermediate strip is continuously annealed.
    Type: Grant
    Filed: March 22, 2020
    Date of Patent: March 1, 2022
    Assignee: VACUUMSCHMELZE GMBH & CO. KG
    Inventor: Niklas Volbers
  • Patent number: 11239012
    Abstract: A process for producing grain-oriented electrical steel strip by means of thin slab continuous casting and which includes continuously casting the smelt by thin slab continuous casting, subjecting the thin slabs to homogenization annealing at a maximum temperature of 1250° C. and heating to a temperature between 1350° C. and 1380° C., and continuously hot rolling the thin slabs to form a hot-rolled strip, with cooling and reeling the hot-rolled strip to form a coil and cold rolling the hot-rolled strip to a nominal thickness, with subjecting the cold-rolled strip to recrystallization, decarburization and nitridation annealing, which includes a decarburization annealing phase and a subsequent nitridation annealing phase, with an intermediate reduction annealing phase being interposed between the decarburization annealing phase and the nitridation annealing phase, whereby a cold-rolled strip is obtained, which primary recrystallized grains have a circle equivalent mean size (diameter) between 22 ?m and 25 ?m.
    Type: Grant
    Filed: March 4, 2015
    Date of Patent: February 1, 2022
    Inventors: Andreas Boettcher, Christian Klinkenberg, Ingo Schuster
  • Patent number: 11230745
    Abstract: A non-oriented electrical steel sheet according to one embodiment of the present invention comprises, by weight, 1.0% to 4.0% of Si, 0.001% to 0.01% of Al, 0.002% to 0.009% of S, 0.01% to 0.3% of Mn, 0.001% to 0.004% of N, 0.004% or less (0% exclusive) of C, 0.003% or less (0% exclusive) of Ti, 0.005% to 0.07% of Cu, 0.05% to 0.2% of either or both of Sn and P, and a balance amount of Fe and impurities.
    Type: Grant
    Filed: December 23, 2016
    Date of Patent: January 25, 2022
    Assignee: POSCO
    Inventor: Se Il Lee
  • Patent number: 11186888
    Abstract: In the production of a grain-oriented electrical steel sheet by hot rolling a slab containing Si: 2.0-8.0 mass % and no inhibitor-forming ingredients, cold rolling, subjecting to a decarburization annealing, applying an annealing separator composed mainly of MgO and containing a Ti compound(s) and subjecting to a finish annealing, an atmosphere in the heating process of the decarburization annealing is rendered into a dry atmosphere having a dew point of not higher than 0° C. and a Ti amount (Ti(a)) and a N amount (N(a)) contained in an iron matrix after the removal of a forsterite coating and a Ti amount (Ti(b)) and a N amount (N(b)) contained in the steel sheet having a forsterite coating are made to satisfy relationships as N(b)?0.0050 mass %, N(b)/N(a)?4, and Ti(b)/Ti(a)?4.
    Type: Grant
    Filed: July 6, 2016
    Date of Patent: November 30, 2021
    Assignee: JFE STEEL CORPORATION
    Inventors: Takeshi Imamura, Masanori Takenaka
  • Patent number: 11189407
    Abstract: A grain-oriented electrical steel sheet includes: a steel sheet; and an amorphous oxide layer that is formed on the steel sheet, in which a glossiness of a surface is 150% or higher.
    Type: Grant
    Filed: July 13, 2018
    Date of Patent: November 30, 2021
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Shinsuke Takatani, Yoshiyuki Ushigami, Hiroyasu Fujii, Shuichi Nakamura, Takeshi Imai
  • Patent number: 11114227
    Abstract: A non-oriented electrical steel sheet has low iron loss even under inverter excitation and can be suitably used as the iron core of a motor. The non-oriented electrical steel sheet has a specific chemical composition and an average grain size r of 40 ?m to 120 ?m. An area ratio R of a total area of grains having a grain size of ? or less of the thickness of the steel sheet to a cross-sectional area of the steel sheet is 2% or greater, and the average grain size r (?m) and the area ratio R (%) satisfy a condition represented by Expression (1), R>?2.4×r+200 (1).
    Type: Grant
    Filed: December 14, 2016
    Date of Patent: September 7, 2021
    Assignee: JFE STEEL CORPORATION
    Inventors: Masanori Uesaka, Kunihiro Senda, Takeshi Omura
  • Patent number: 11098393
    Abstract: There are provided a very thin martensitic stainless steel foil and a manufacturing method thereof, which are capable of reducing shape defects and the like. A martensitic stainless steel foil of the present invention has a thickness of at most 35 ?m, and having a steepness of at most 0.75% when the steel foil has a length of 650 mm. Preferably, a metallographic structure in a cross-section of the steel foil is a ferrite structure, in which carbides are dispersed. More preferably, the steel foil consisting of, by mass, 0.25% to 1.5% C, 10% to 18% Cr, at most 1.0% Si (exclusive of 0%), at most 1.5% Mn (exclusive of 0%), at most 3.0% Mo (inclusive of 0%), and the balance of Fe with inevitable impurities.
    Type: Grant
    Filed: March 8, 2017
    Date of Patent: August 24, 2021
    Assignee: HITACHI METALS, LTD.
    Inventor: Takuya Okamoto
  • Patent number: 11072861
    Abstract: A grain-oriented electrical steel sheet according to one embodiment of the present invention includes a steel sheet and an insulation coating, in which the insulation coating contains a first metal phosphate, which is a metal phosphate of one or two more metals selected from Al, Fe, Mg, Mn, Ni, and Zn; a second metal phosphate, which is a metal phosphate of one or two more metals selected from Co, Mo, V, W, and Zr; and colloidal silica, the insulation coating does not contain chromate, and an elution amount of phosphoric acid of the insulation coating as determined by boiling the grain-oriented electrical steel sheet in a boiled pure water for 10 minutes, then measuring an elution amount of phosphoric acid into the pure water, and dividing the amount of phosphoric acid by the area of the insulation coating of the boiled grain-oriented electrical steel sheet is 30 mg/m2 or less.
    Type: Grant
    Filed: September 28, 2016
    Date of Patent: July 27, 2021
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Kazutoshi Takeda, Fumikazu Andou, Tomoya Suenaga, Shuichi Yamazaki, Masaru Takahashi
  • Patent number: 11066717
    Abstract: A manufacturing method of an oriented electrical steel sheet according to an exemplary embodiment of the present invention includes: a step of manufacturing a steel slab including one kind or more among Si at 2 to 7%, Sn at 0.03 to 0.10%, and Sb at 0.01 to 0.05% as wt %; a step of hot-rolling the steel slab to manufacture a hot rolled sheet; a step of cold-rolling the hot rolled sheet to manufacture a cold rolled sheet; a step of decarburizing and nitriding the cold rolled sheet for primary recrystallization annealing; a step of coating and drying an annealing separating agent on the primary recrystallization-annealed cold rolled sheet; and a step of secondary recrystallization-annealing the cold rolled sheet coated with the annealing separating agent.
    Type: Grant
    Filed: December 20, 2016
    Date of Patent: July 20, 2021
    Assignee: POSCO
    Inventors: Chang Soo Park, Min Soo Han, Jong Ho Park, Hyung Don Joo, Yun Su Kim
  • Patent number: 11060162
    Abstract: The non-oriented electrical steel sheet according to one embodiment of the present invention includes: by weight, 2.0% to 4.0% of Si; 0.001% to 2.0% of Al; 0.0005% to 0.009% of S; 0.02% to 1.0% of Mn, 0.0005% to 0.004% of N; 0.004% or less of C (excluding 0%); 0.005% to 0.07% of Cu; 0.0001% to 0.007% of O; individually or in a total amount of 0.05% to 0.2% of Sn or P; and the remainder comprising Fe and impurities; wherein the non-oriented electrical steel sheet is composed of a surface portion to 2 ?m from the surface of the steel sheet in the thickness direction and a base portion exceeding 2 ?m from the surface of the steel sheet in the thickness direction, and wherein the number of surfides having a diameter of 10 nm to 100 nm is larger than the number of the nitrides having a diameter of 10 nm to 100 nm, in the same area of base portion.
    Type: Grant
    Filed: December 19, 2017
    Date of Patent: July 13, 2021
    Assignee: POSCO
    Inventors: Se Il Lee, June Soo Park, Jae Hoon Kim
  • Patent number: 11056256
    Abstract: Iron loss is reduced by increasing magnetic flux density. Disclosed is a non-oriented electrical steel sheet has a chemical composition containing, by mass %, C: 0.0050% or less, Si: 1.50% or more and 4.00% or less, Al: 0.500% or less, Mn: 0.10% or more and 5.00% or less, S: 0.0200% or less, P: 0.200% or less, N: 0.0050% or less, O: 0.0200% or less, and Ca: 0.0010% or more and 0.0050% or less, with the balance being Fe and inevitable impurities, in which the non-oriented electrical steel sheet has an Ar3 transformation temperature of 700° C. or higher, a grain size of 80 ?m or more and 200 ?m or less, and a Vickers hardness of 140 HV or more and 230 HV or less.
    Type: Grant
    Filed: August 30, 2017
    Date of Patent: July 6, 2021
    Assignee: JFE STEEL CORPORATION
    Inventors: Yoshihiko Oda, Tomoyuki Okubo, Yoshiaki Zaizen, Masanori Uesaka, Tatsuhiko Hiratani
  • Patent number: 11041222
    Abstract: The invention relates to a non-oriented electrical steel strip or sheet, in particular for electrical engineering applications, an electrical engineering component produced from such an electrical steel strip or sheet, a process for producing an electrical steel strip or sheet and the use of such an electrical steel strip or sheet in components for electrical engineering applications.
    Type: Grant
    Filed: May 11, 2018
    Date of Patent: June 22, 2021
    Assignee: thyssenkrupp AG
    Inventors: Olaf Fischer, Sebastian Sieron, Silke Strauss, Karl Telger, Marco Tietz, Anton Vidovic
  • Patent number: 11031162
    Abstract: Disclosed are an oriented electrical steel sheet and a manufacturing method thereof. An exemplary embodiment of the present invention provides a method of manufacturing an oriented electrical steel sheet, including: providing a slab including Si at 1.0 to 4.0 wt %, C at 0.1 to 0.4 wt %, and the remaining portion including Fe and other inevitably incorporated impurities; reheating the slab; producing a hot rolled steel sheet by hot rolling the slab; performing annealing of the hot rolled steel sheet; cold rolling the annealed hot rolled steel sheet; decarburizing and annealing the cold rolled steel sheet; cold rolling the decarburized and annealed steel sheet; and final annealing the cold rolled steel sheet.
    Type: Grant
    Filed: December 8, 2014
    Date of Patent: June 8, 2021
    Assignee: POSCO
    Inventors: Hyun-Seok Ko, Kyu-Seok Han, Hyung-Ki Park, Jin-Wook Seo, Jae-Soo Lim, Hyung Don Joo
  • Patent number: 11021771
    Abstract: A non-oriented electrical steel sheet contains, as a chemical composition, by mass %, C: more than 0% and 0.0050% or less, Si: 3.0% to 4.0%, Mn: 1.0% to 3.3%, P: more than 0% and less than 0.030%, S: more than 0% and 0.0050% or less, sol. Al: more than 0% and 0.0040% or less, N: more than 0% and 0.0040% or less, O: 0.0110% to 0.0350%, Sn: 0% to 0.050%, Sb: 0% to 0.050%, Ti: more than 0% and 0.0050% or less, and a remainder including Fe and impurities, in which Sn+Sb: 0.050% or less, Si?0.5×Mn: 2.0% or more, and an O content in a sheet thickness central portion excluding a surface layer portion which is a range from a front surface and a rear surface to a position of 10 ?m in a depth direction is less than 0.0100%.
    Type: Grant
    Filed: January 16, 2018
    Date of Patent: June 1, 2021
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Hiroyoshi Yashiki, Yoshiaki Natori, Kazutoshi Takeda, Susumu Mukawa, Takuya Matsumoto, Koji Fujita, Takashi Morohoshi, Masafumi Miyazaki
  • Patent number: 11008633
    Abstract: A steel containing C: not more than 0.0050%, Si: 0.1-5.0%, Mn: 0.02-3.0%, sol. Al: not more than 0.0050%, P: not more than 0.2%, S: not more than 0.0050%, N: not more than 0.0040%, T. Ca: 0.0010-0.0080%, T. O: not more than 0.0100% and having (T. Ca/T. O) of not less than 0.50 but not more than 2.0 by decarburizing to a C content of not more than 0.0050%, adding Si, decreasing Al as much as possible, and adding Ca is melted to form a slab. The slab is subjected to a hot rolling at a coiling temperature of not lower than 550° C., a cold rolling and a finish annealing, or the slab is subjected to a hot rolling, a hot band annealing at a temperature of 900-1150° C., a cold rolling and a finish annealing to thereby produce a non-oriented electrical steel sheet.
    Type: Grant
    Filed: January 13, 2017
    Date of Patent: May 18, 2021
    Assignee: JFE Steel Corporation
    Inventors: Masanori Uesaka, Tadashi Nakanishi, Seiji Nabeshima, Tomoyuki Okubo, Yoshihiko Oda, Hiroaki Nakajima
  • Patent number: 10975451
    Abstract: Methods for producing non-oriented electrical steel sheets comprising steps including hot rolling a slab having a chemical composition comprising C: not more than 0.01 mass %, Si: not more than 6 mass %, Mn: 0.05-3 mass %, P: not more than 0.2 mass %, Al: not more than 2 mass %, N: not more than 0.005 mass %, S: not more than 0.01 mass %, Ga: not more than 0.0005 mass %, and the remainder being Fe and inevitable impurities, pickling without conducting hot band annealing or after conducting hot band annealing or self-annealing, subjecting to one or more cold rollings including an intermediate annealing therebetween and a finish annealing, and forming an insulation coating, an average heating rate from 500 to 800° C. in the heating process of the finish annealing is not less than 50° C./s, whereby a non-oriented electrical steel sheet having excellent magnetic properties is obtained even if hot band annealing is omitted.
    Type: Grant
    Filed: June 27, 2016
    Date of Patent: April 13, 2021
    Assignee: JFE STEEL CORPORATION
    Inventors: Hiroaki Nakajima, Tomoyuki Okubo, Tadashi Nakanishi, Yoshihiko Oda
  • Patent number: 10907234
    Abstract: A grain-oriented electrical steel sheet includes: a chemical composition represented by, in mass %, Si: 1.8% to 7.0%, Cu: 0.03% to 0.60%, and the balance: Fe and impurities; and a primary coating film containing forsterite on a surface of the steel sheet, in which a Cu/Fe light-emitting intensity ratio at an interface region between the primary coating film and the surface of the steel sheet is 0.30 or less.
    Type: Grant
    Filed: October 26, 2016
    Date of Patent: February 2, 2021
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Hiroshi Fujimura, Fumiaki Takahashi, Takashi Kataoka
  • Patent number: 10900113
    Abstract: In a grain-oriented electrical steel sheet manufacturing process of processing a steel slab having a predetermined composition to a final sheet thickness and then performing primary recrystallization annealing and nitriding treatment, the nitriding treatment is performed in at least two stages of temperatures including high-temperature nitriding and low-temperature nitriding, and a residence time in the high-temperature nitriding is 3 seconds or more and 600 seconds or less. In this way, nitrogen is efficiently diffused into the steel of the steel sheet before secondary recrystallization to precipitate AlN. Such a method can manufacture a grain-oriented electrical steel sheet having excellent magnetic property.
    Type: Grant
    Filed: September 4, 2015
    Date of Patent: January 26, 2021
    Assignee: JFE STEEL CORPORATION
    Inventors: Yukihiro Shingaki, Hirotaka Inoue
  • Patent number: 10844452
    Abstract: The disclosure contains, in mass % or mass ppm: C: 0.005% or less, Si: 2.0% to 5.0%, Mn: 0.01% to 0.5%, sol.Al: 10 ppm or less, N: 15 ppm or less, S and Se: each 10 ppm or less, and three or more selected from Sn, Sb, Cr, P, Mo and B whose contents satisfy a relational expression of 0.16?[% Sn]+[% Sb]+[% Cr]+2×[% P]+[% Mo]+[% B]?0.50, the balance being Fe and inevitable impurities, where a number of times of repeated bending in a bend test is 10 or more.
    Type: Grant
    Filed: June 9, 2016
    Date of Patent: November 24, 2020
    Assignee: JFE STEEL CORPORATION
    Inventors: Yukihiro Shingaki, Yasuyuki Hayakawa, Masanori Takenaka
  • Patent number: 10815545
    Abstract: A grain-oriented electrical steel plate of an exemplary embodiment of the present invention has a groove formed on a surface, wherein a curvature radius RBb at a position where a depth of the groove is maximum is 0.2 ?m to 100 ?m, and a curvature radius RSb on the groove surface from the position where the depth of the groove is maximum to a quarter-way position of the depth D of the groove is 4 ?m to 130 ?m.
    Type: Grant
    Filed: December 21, 2015
    Date of Patent: October 27, 2020
    Assignee: POSCO
    Inventors: Oh-Yeoul Kwon, Won-Gul Lee, Seong-Cheol Hong, Gyoo-Taek Lee, Jong-Tae Park, Choong Soo Lim
  • Patent number: 10793929
    Abstract: Disclosed are a grain-oriented electrical steel sheet and a method of manufacturing the same. The method for manufacturing a grain-orientated electrical steel sheet according to an exemplary embodiment of the present invention includes: providing an electrical steel sheet before forming primary recrystallization or after forming the primary recrystallization; and forming a groove in a surface of the electrical steel sheet by radiating laser and simultaneously spraying gas onto the electrical steel sheet, in which energy density Ed and a laser scanning speed Vs of the radiated laser satisfy the following conditions, 1.0 J/mm2?Ed?5.0 J/mm2, 0.0518 mm/?sec?Vs?0.2 mm/?sec.
    Type: Grant
    Filed: July 22, 2014
    Date of Patent: October 6, 2020
    Assignee: POSCO
    Inventors: Oh Yeoul Kwon, Sun Mi Shin, Chang Ho Moon, Won Gul Lee
  • Patent number: 10745773
    Abstract: This device scans a high-energy beam in a direction traversing a feed path of a grain-oriented electrical steel sheet having subjected to final annealing so as to irradiate a surface of the steel sheet being passed through with the high-energy beam to thereby perform magnetic domain refinement, the device including an irradiation mechanism for scanning the high-energy beam in a direction orthogonal to the feed direction of the steel sheet, in which the irradiation mechanism has a function of having the scanning direction of the high-energy beam oriented diagonally, relative to the orthogonal direction, toward the feed direction at an angle determined based on a sheet passing speed of the steel sheet on the feed path.
    Type: Grant
    Filed: December 25, 2012
    Date of Patent: August 18, 2020
    Assignee: JFE STEEL CORPORATION
    Inventors: Seiji Okabe, Shigehiro Takajo, Yasushi Kitani
  • Patent number: 10704115
    Abstract: Disclosed is a non-oriented electrical steel sheet that is low in iron loss and exhibits excellent magnetic properties even when subjected to final annealing at high temperature. The non-oriented electrical steel sheet can be obtained from a steel (low-Al steel) having a chemical composition containing, in mass %, C: 0.005% or less, Si: 1.0% to 4.5%, Mn: 0.02% to 2.0%, Sol. Al: 0.001% or less, P: 0.2% or less, S+Se: 0.0010% or less, N: 0.005% or less, O: 0.005% or less, and Cu: 0.02% to 0.30%, and the balance consisting of Fe and incidental impurities.
    Type: Grant
    Filed: October 21, 2015
    Date of Patent: July 7, 2020
    Assignee: JFE STEEL CORPORATION
    Inventors: Tomoyuki Okubo, Yoshihiko Oda, Tadashi Nakanishi
  • Patent number: 10676801
    Abstract: The present invention relates generally to steel compositions, methods of manufacturing the compositions and using the compositions to produce rimfire ammunition cartridges. The steel compositions for use in the rimfire cartridges are processed through cold-rolling and annealing steps to create suitable physical properties.
    Type: Grant
    Filed: December 16, 2015
    Date of Patent: June 9, 2020
    Assignee: Greer Steel Company
    Inventors: Douglas B. Campbell, Todd Daenzer
  • Patent number: 10610964
    Abstract: A grain-oriented electrical steel sheet includes: a base steel sheet; a primary film formed on a surface of the base steel sheet; and a tension insulation coating formed on a surface of the primary film, in which a magnetic domain control is performed by irradiating the tension insulation coating with a laser from above. When a strip-like sample having a length of 300 mm in a direction parallel to a rolling direction of the grain-oriented electrical steel sheet and a length of 60 mm in a direction parallel to a transverse direction is extracted from the grain-oriented electrical steel sheet, a range from a surface of the tension insulation coating to a depth position of 5 ?m toward the base steel sheet side from an interface between the base steel sheet and the primary film is removed by pickling at least one surface of the sample, and a warpage amount of the sample is thereafter measured, the warpage amount satisfies predetermined conditions.
    Type: Grant
    Filed: May 8, 2015
    Date of Patent: April 7, 2020
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Satoshi Arai, Hideyuki Hamamura, Kenichi Murakami, Hiroyasu Fujii, Hideyuki Kobayashi, Norikazu Fujii, Masato Mizokami
  • Patent number: 10584406
    Abstract: An electrical steel sheet has a composition including C: less than 0.010 mass %, Si: 1.5˜10 mass % and the balance being Fe and incidental impurities, wherein a main orientation in a texture of a steel sheet is <111>//ND and an intensity ratio relative to randomly oriented specimen of the main orientation is not less than 5 and, preferably an intensity ratio relative to randomly oriented specimen of {111}<112> orientation is not less than 10, an intensity ratio relative to randomly oriented specimen of {310}<001> orientation is not more than 3 and Si concentration has a gradient that it is high at a side of a surface layer and low at a central portion in the thickness direction and a maximum value of the Si concentration is not less than 5.5 mass % and a difference between maximum and minimum values is not less than 0.5 mass %.
    Type: Grant
    Filed: January 22, 2013
    Date of Patent: March 10, 2020
    Assignee: JFE Steel Corporation
    Inventors: Takeshi Imamura, Minoru Takashima, Tatsuhiko Hiratani
  • Patent number: 10541071
    Abstract: An electrical steel sheet includes: a specific chemical composition; a crystal grain diameter of 20 ?m to 300 ?m; and a texture satisfying Expression 1, Expression 2, and Expression 3 when the accumulation degree of the (001)[100] orientation is represented as ICube and the accumulation degree of the (011)[100] orientation is represented as IGoss. IGoss+ICube?10.5??Expression 1 IGoss/ICube?0.50??Expression 2 ICube?2.
    Type: Grant
    Filed: June 26, 2015
    Date of Patent: January 21, 2020
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Hirotoshi Tada, Satoshi Kano, Ichiro Tanaka, Hiroyoshi Yashiki
  • Patent number: 10434606
    Abstract: Provided is a grain-oriented electrical steel sheet including a steel sheet having a steel sheet surface in which a groove, which extends in a direction intersecting a rolling direction and of which a groove depth direction matches a sheet thickness direction, is formed. When an average value of a groove depth in a sheet thickness direction at a central portion of the groove in a longitudinal groove direction is set as an average groove depth D, a straight line, which connects a first point at which a groove depth in the sheet thickness direction becomes 0.05×D and a second point at which the groove depth becomes 0.
    Type: Grant
    Filed: April 19, 2016
    Date of Patent: October 8, 2019
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Hideyuki Hamamura, Tatsuhiko Sakai, Fumiaki Takahashi, Hisashi Mogi, Shunsuke Okumura, Hirofumi Imai
  • Patent number: 10385414
    Abstract: An unoriented silicon steel having high magnetic conductivity and low iron loss at a working magnetic density of 1.0-1.5 T and method for manufacturing same. By proper deoxidation control in a RH refining and high-temperature treatment for a short time in a normalizing step, the method can reduce the amount of inclusions in the silicon steel and improve grain shape, so as to improve the magnetic conductivity and iron loss of the unoriented silicon steel at a magnetic density of 1.0-1.5 T.
    Type: Grant
    Filed: March 29, 2012
    Date of Patent: August 20, 2019
    Assignee: Baoshan Iron & Steel Co., Ltd.
    Inventors: Liang Zou, Bo Wang, Xiandong Liu, Aihua Ma, Shishu Xie, Hongxu Hei
  • Patent number: 10347405
    Abstract: An alloy of Fe100-a-b-c-d-x-y-zCuaNbbMcTdSixByZz and up to 1 atomic % impurities; M is one or more of Mo or Ta, T is one or more of V, Cr, Co or Ni and Z is one or more of C, P or Ge, wherein 0.0 atomic %?a<1.5 atomic %, 0.0 atomic %?b<3.0 atomic %, 0.2 atomic %?c?4.0 atomic %, 0.0 atomic %?d<5.0 atomic %, 12.0 atomic %<x<18.0 atomic %, 5.0 atomic %<y<12.0 atomic % and 0.0 atomic %?z<2.0 atomic %, and wherein 2.0 atomic %?(b+c)?4.0 atomic %, produced in the form of a strip and having a nanocrystalline structure in which at least 50% by volume of the grains have an average size of less than 100 nm, a remanence ratio Jr/Js<0.02, Jr being the remanent polarization and Js being the saturation polarization, and a coercitive field strength Hc which is less than 1% of the anisotropic field strength Ha and/or less than 10 A/m.
    Type: Grant
    Filed: October 11, 2013
    Date of Patent: July 9, 2019
    Assignee: VACUUMSCHMELZE GMBH & CO. KG.
    Inventors: Giselher Herzer, Mie Marsilius, Christian Polak
  • Patent number: 10297375
    Abstract: A method of manufacturing a grain-oriented electrical steel sheet, includes: a laser processing process of forming a laser processed portion by irradiating a region on one end side of a steel sheet in a width direction after being subjected to a cold rolling process with a laser beam along a rolling direction of the steel sheet; and a finish annealing process of coiling the steel sheet with the laser processed portion formed thereon in a coil shape and performing a finish annealing on the coil-shaped steel sheet. In the laser processing process, a melted-resolidified portion having a depth of greater than 0% and equal to or less than 80% of a sheet thickness of the steel sheet is formed by the irradiation of the laser beam at a position corresponding to the laser processed portion.
    Type: Grant
    Filed: November 6, 2013
    Date of Patent: May 21, 2019
    Assignee: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Koji Hirano, Yoshio Nakamura, Shohji Nagano, Seiichiro Cho
  • Patent number: 10240220
    Abstract: Embodiments of the present invention comprises melting scrap steel into molten steel; decarburizing the molten steel and adding alloys; transferring the steel to ladles and casting the steel into slabs; hot rolling the slabs into sheets; pickling the sheets; annealing the sheets; cold rolling the sheets; and performing one or more of tension leveling, a rough rolling, or a coating process on the sheets after cold rolling, without an intermediate annealing process between the cold rolling and the tension leveling, the rough rolling, or the coating process. The sheet is sent to the customer for stamping and customer annealing. The new process provides an electrical steel with the similar, same, or better magnetic properties than an electrical steel manufactured using the traditional processing with an intermediate annealing step after cold rolling.
    Type: Grant
    Filed: January 11, 2013
    Date of Patent: March 26, 2019
    Assignee: NUCOR CORPORATION
    Inventors: Theodore E. Hill, Eric E. Gallo
  • Patent number: 10214791
    Abstract: A non-oriented electrical steel sheet containing: in mass%, C: 0.005% or less; Si: 0.1% to 2.0%; Mn: 0.05% to 0.6%; P: 0.100% or less; and Al: 0.5% or less, in which 10 pieces/?m3 or less in number density of non-magnetic precipitate AlN having an average diameter of 10 nm to 200 nm are contained, and an average magnetic flux density B50 in a rolling direction and in a direction perpendicular to rolling is 1.75 T or more. This non-oriented electrical steel sheet can be manufactured by two methods of a method of performing hot rolling annealing at a temperature of 750° C. to an Ac1 transformation point and a method of setting a coil winding temperature to 780° C. or higher and performing self annealing.
    Type: Grant
    Filed: May 30, 2017
    Date of Patent: February 26, 2019
    Assignee: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Masahiro Fujikura, Yoshiyuki Ushigami, Tesshu Murakawa, Shinichi Kanao, Makoto Atake, Takeru Ichie, Kojiro Hori
  • Patent number: 10208372
    Abstract: A grain-oriented electrical steel sheet being a grain-oriented electrical steel sheet containing Si of 0.8 mass % to 7 mass %, Mn of 0.05 mass % to 1 mass %, B of 0.0005 mass % to 0.0080 mass %, each content of Al, C, N, S, and Se of 0.005 mass % or less, and a balance being composed of Fe and inevitable impurities and having a glass coating film made of composite oxide mainly composed of forsterite on the steel sheet surface, in which when glow discharge optical emission spectrometry (GDS) to the surface of a secondary coating film formed on the surface of the glass coating film under a predetermined condition is performed, a peak, of B, in emission intensity having a peak position in emission intensity different from a peak position, of Mg, in emission intensity is obtained and the peak position, of B, in emission intensity from the steel sheet surface is deeper than the peak position, of Mg, in emission intensity.
    Type: Grant
    Filed: January 12, 2012
    Date of Patent: February 19, 2019
    Assignee: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Fumiaki Takahashi, Yoshiyuki Ushigami, Kazumi Mizukami, Shuichi Nakamura, Norikazu Fujii, Norihiro Yamamoto, Masahide Urago
  • Patent number: 10192662
    Abstract: In a method for producing a grain-oriented electrical steel sheet by comprising a series of steps of hot rolling a raw steel material comprising C: 0.002-0.10 mass %, Si: 2.0-8.0 mass %, and Mn: 0.005-1.0 mass %, subjecting the steel sheet to a hot band annealing as required, cold rolling to obtain a cold rolled sheet having a final sheet thickness, subjecting the steel sheet to primary recrystallization annealing combined with decarburization annealing, applying an annealing separator to the steel sheet surface and then subjecting to final annealing, rapid heating is performed at a rate of not less than 50° C./s in a region of 200-700° C. in the heating process of the primary recrystallization annealing, and the steel sheet is held at any temperature of 250-600° C. in the above region for 1-10 seconds, while a soaking process of the primary recrystallization annealing is controlled to a temperature range of 750-900° C., a time of 90-180 seconds and PH2O/PH2 in an atmosphere of 0.25-0.
    Type: Grant
    Filed: February 12, 2014
    Date of Patent: January 29, 2019
    Assignee: JFE Steel Corporation
    Inventors: Makoto Watanabe, Takeshi Imamura, Ryuichi Suehiro, Toshito Takamiya
  • Patent number: 10192669
    Abstract: A vector-magnetic-property-controlling material according to the present embodiment is subjected to a scratching process in two directions that intersect on the surface of a steel material. An iron core according to the present embodiment is configured from an oriented magnetic steel material which has been subjected to a scratching process in two directions that intersect on the surface thereof.
    Type: Grant
    Filed: November 21, 2014
    Date of Patent: January 29, 2019
    Assignees: TOSHIBA INDUSTRIAL PRODUCTS & SYSTEMS CORPORATION, NATIONAL UNIVERSITY CORPORATION OITA UNIVERSITY
    Inventors: Masato Enokizono, Hiromu Shiota, Eiji Shimomura, Tsuyoshi Masuda
  • Patent number: 10176910
    Abstract: The present invention provides a non-oriented silicon steel with excellent magnetic properties and a manufacturing process therefor. During the manufacturing process of the present invention, the temperature T of the molten steel of steel tapped from a converter during steelmaking and the carbon content [C] and the free oxygen content [O] comply with the following formula: 7.27×103?[O][C]e(?5000/T)?2.99×104, and the final annealing step uses tension annealing at a low temperature for a short time. A non-oriented silicon steel with a low iron loss, and excellent anisotropy of iron loss can be obtained by means of the manufacturing process of the present invention.
    Type: Grant
    Filed: December 11, 2012
    Date of Patent: January 8, 2019
    Assignee: Baoshan Iron & Steel Co., Ltd.
    Inventors: Shishu Xie, Xiandong Liu, Xiao Chen, Hongxu Hei, Bo Wang, Aihua Ma, Liang Zou, Huawei Zhang, Wei Cao, Feng Zhang, Junliang Liu
  • Patent number: 10134513
    Abstract: Provided is a method for manufacturing a high silicon steel sheet having excellent producibility and magnetic properties. The method includes: casting a molten metal as a strip having a thickness of 5 mm or less, the molten metal comprising, by weight %, C: 0.05% or less (excluding 0%), N: 0.05% or less (excluding 0%), Si: 4% to 7%, Al: 0.5% to 3%, Si+Al: 4.5% to 8%, and the balance of Fe and inevitable impurities; hot-rolling the cast strip at a temperature of 800° C. or higher; annealing the hot-rolled strip at a temperature within a range of 900° C. to 1200° C.; cooling the annealed strip; warm-rolling the quenched strip at a temperature within a range of 300° C. to 700° C.; and finally annealing the warm-rolled strip at a temperature within a range of 800° C. to 1200° C.
    Type: Grant
    Filed: December 20, 2012
    Date of Patent: November 20, 2018
    Assignee: POSCO
    Inventors: Byung-Deug Hong, Jin-Mo Koo, Jae-Kon Lee, Sung-Jin Park, Sang-Hoon Kim
  • Patent number: 10125416
    Abstract: The present invention provides a steel for nitrocarburizing having excellent mechanical workability before nitrocarburizing, and showing excellent fatigue properties after nitrocarburizing, which is suitable for applying in mechanical structural components for automobiles etc. prepared by adjusting the composition so that it contains in mass %, C: 0.01% or more and less than 0.10%, Si: 1.0% or less, Mn: 0.5% to 3.0%, P: 0.02% or less, S: 0.06% or less, Cr: 0.3% to 3.0%, Mo: 0.005% to 0.4%, V: 0.02% to 0.5%, Nb: 0.003% to 0.15%, Al: 0.005% to 0.2%, and Sb: 0.0005% to 0.02%, and the balance including Fe and incidental impurities, and setting the area ratio of bainite phase to the whole microstructure to more than 50%.
    Type: Grant
    Filed: July 22, 2013
    Date of Patent: November 13, 2018
    Assignees: JFE STEEL CORPORATION, JFE BARS AND SHAPES
    Inventors: Yasuhiro Omori, Kiyoshi Uwai, Shinji Mitao, Takashi Iwamoto, Keisuke Ando, Kunikazu Tomita
  • Patent number: 10096414
    Abstract: Disclosed are a non-oriented electrical steel sheet and a method of manufacturing the same. The non-oriented electrical steel sheet of the present invention includes 0.005 wt % or less of C, 1.0-4.0 wt % of Si, 0.1-0.8 wt % of Al, 0.01-0.1 wt % of Mn, 0.02-0.3 wt % of P, 0.005 wt % or less of N, 0.001-0.005 wt % of S, 0.005 wt % or less of Ti, 0.01-0.2 wt % of at least one of Sn and Sb, and the remainder including Fe and other impurities unavoidably added thereto, wherein Mn, Al, P, and S may respectively fulfill the empirical formula 0.8?{[Mn]/(100*[S])+[Al]}[P]?40, wherein [Mn], [Al], [P], and [S] respectively refer to weight percentages of Mn, Al, P, and S.
    Type: Grant
    Filed: December 28, 2012
    Date of Patent: October 9, 2018
    Assignee: POSCO
    Inventors: Junesoo Park, Byung-Keun Bae, Yong-Soo Kim, Su-Yong Sin
  • Patent number: 10020103
    Abstract: A grain oriented electrical steel sheet reduces local exfoliation of insulating coating films and thus has excellent corrosion resistance and insulation properties. The grain oriented electrical steel sheet may be obtained by, assuming that a1 (?m) is a film thickness of the insulating coating at the floors of linear grooves and a2 (?m) is a film thickness of the insulating coating on a surface of the steel sheet at portions other than the linear grooves, controlling a1 and a2 to satisfy the following formulas (1) and (2): 0.3 ?m?a2?3.5 ?m??(1), and a1/a2?2.5??(2).
    Type: Grant
    Filed: September 28, 2011
    Date of Patent: July 10, 2018
    Assignee: JFE Steel Corporation
    Inventors: Makoto Watanabe, Seiji Okabe, Toshito Takamiya
  • Patent number: 9997283
    Abstract: Provided is a grain-oriented electric steel sheet having superior magnetic property and to a grain-oriented electric steel sheet including 2.0 to 4.5 weight % of Si, 0.001 to 0.10 weight % of C, 0.010 weight % or lower of Al, 0.08 weight % or lower of Mn, 0.005 weight % or lower of N, 0.002 to 0.050 weight % of S, the remainder being Fe and other unavoidable impurities. The steel sheet having been subjected to secondary recrystallization using at least any one of grain boundary-segregated elementary S and an FeS precipitate as a grain growth inhibitor.
    Type: Grant
    Filed: December 9, 2015
    Date of Patent: June 12, 2018
    Assignee: POSCO
    Inventors: Kyu-Seok Han, Jae-Soo Lim, Byung-Deug Hong, Chan-Hee Han
  • Patent number: 9978488
    Abstract: A steel slab having a chemical composition including C: not more than 0.005 mass %, Si: not more than 4 mass %, Mn: 0.03-2 mass %, P: not more than 0.2 mass %, S: not more than 0.004 mass %, Al: not more than 2 mass %, N: not more than 0.004 mass %, Se: not more than 0.0010 mass % and the balance being Fe and inevitable impurities is subjected to hot rolling, cold rolling and recrystallization annealing up to 740° C. at an average heating rate of not less than 100° C./s to produce a semi-processed non-oriented electrical steel sheet being high in the magnetic flux density and low in the iron loss after stress relief annealing.
    Type: Grant
    Filed: November 21, 2013
    Date of Patent: May 22, 2018
    Assignee: JFE STEEL CORPORATION
    Inventors: Yoshiaki Zaizen, Yoshihiko Oda, Hiroaki Toda, Kazuhiro Hanazawa
  • Patent number: 9953752
    Abstract: A method for producing grain-oriented electrical steel sheets includes subjecting a steel slab to hot rolling to obtain a hot rolled sheet, the steel slab having a composition consisting of, by mass % or mass ppm, C: 0.08% or less, Si: 2.0% to 4.5% and Mn: 0.5% or less, S, Se, and O: less than 50 ppm each, sol.Al: less than 100 ppm, N: 80 ppm or less, and the balance being Fe and incidental impurities, and satisfying the relation of sol.Al (ppm)?N (ppm)×(26.98/14.00)?30 ppm; then subjecting the hot rolled sheet to annealing and rolling to obtain a cold rolled sheet; then subjecting the cold rolled sheet to nitriding treatment, under specific condition, before, during or after primary recrystallization annealing; then applying an annealing separator on the cold rolled sheet; and subjecting the cold rolled sheet to secondary recrystallization annealing.
    Type: Grant
    Filed: December 25, 2013
    Date of Patent: April 24, 2018
    Assignee: JFE STEEL CORPORATION
    Inventors: Yukihiro Shingaki, Hiroi Yamaguchi, Yuiko Wakisaka, Hiroshi Matsuda, Takashi Terashima
  • Patent number: 9947446
    Abstract: The pickling loss when a hot-rolled steel sheet having a predetermined chemical composition is annealed at 1000° C. for 30 seconds in a nitrogen atmosphere and then immersed in a solution of 7% HCl at 80° C. for 60 seconds is in a range of 40 g/m2 or more and 100 g/m2 or less. A hot-rolled steel sheet for production of a non-oriented electrical steel sheet with not only excellent magnetic properties such as iron loss and magnetic flux density but also excellent recyclability and steel sheet surface appearance can thus be obtained.
    Type: Grant
    Filed: October 11, 2013
    Date of Patent: April 17, 2018
    Assignee: JFE Steel Corporation
    Inventors: Hiroaki Toda, Yoshiaki Zaizen, Tadashi Nakanishi, Yoshihiko Oda
  • Patent number: 9939382
    Abstract: The location where forsterite is present is checked in a region from which light excited by an electron beam is emitted when a material containing forsterite is irradiated with an electron beam. The material is preferably a grain oriented electrical steel sheet having a forsterite layer. In addition, it is preferable that the accelerating voltage be 10 kV or more when an electron beam is radiated when the material is a grain oriented electrical steel sheet having a tension coating layer on the forsterite layer.
    Type: Grant
    Filed: March 24, 2014
    Date of Patent: April 10, 2018
    Assignee: JFE Steel Corporation
    Inventors: Masayasu Nagoshi, Takako Yamashita, Yukio Usui, Shigehiro Takajo, Kazuhiro Hanazawa