公开(公告)号：US20220112589A1

公开(公告)日：2022-04-14

申请号：US17421954

申请日：2020-04-16

Applicant: NIPPON STEEL CORPORATION

Inventor： Takuya MITSUNOBU ,  Jun MAKI ,  Hiroshi TAKEBAYASHI ,  Takehiro TAKAHASHI ,  Kohei TOKUDA

IPC: C23C2/06 ,  C23C2/40 ,  C23C2/28 ,  C22C18/04 ,  C22C21/00

Abstract: A plated steel sheet having excellent post-coating corrosion resistance includes: a steel; and a plating layer that is provided on a surface of the steel, in which the plating layer includes, by mass %, Al: 5.00% to 35.00%, Mg: 2.50% to 13.00%, Fe: 5.00% to 35.00%, Si: 0% to 2.00%, Ca: 0% to 2.00%, and a remainder consisting of Zn and impurities, and in a cross section of the plating layer, the area fraction of a Fe2Al5 phase is 5.0% to 60.0%, the area fraction of an eutectic structure of Zn and MgZn2 is 10.0% to 80.0%, the area fraction of a massive MgZn2 phase is 5.0% to 40.0%, and the area fraction of a remainder is 10.0% or less.

公开(公告)号：US20240117476A1

公开(公告)日：2024-04-11

申请号：US18274970

申请日：2022-03-14

Applicant: NIPPON STEEL CORPORATION

Inventor： Masaaki URANAKA ,  Takuya MITSUNOBU ,  Keitaro MATSUDA ,  Hiroshi TAKEBAYASHI ,  Jun MAKI

IPC: C22C38/06 ,  C22C38/02 ,  C22C38/04 ,  C23C2/06

CPC classification number: C22C38/06 ,  C22C38/02 ,  C22C38/04 ,  C23C2/06

Abstract: High strength steel sheet and plated steel sheet having high plateability, LME resistance, and hydrogen embrittlement resistance, that is, steel sheet containing C: 0.05 to 0.40%, Si: 0.2 to 3.0%, Mn: 0.1 to 5.0%, and sol. Al: 0.4 to 1.50%, having an internal oxidation layer including fine granular oxides in a surface layer of the steel sheet, a number density of fine granular oxides in the internal oxidation layer being 4.0/μm2 or more, and including a surface depleted layer with a steel composition not including oxides which satisfies, by mass %, Si≤0.6% and Al≥0.05% at a depth of ½ of the average depth of the internal oxidation layer calculated from the cross-sectional SEM image of the steel sheet, and a plated steel sheet using the same.

公开(公告)号：US20240091842A1

公开(公告)日：2024-03-21

申请号：US17768161

申请日：2019-11-29

Applicant: NIPPON STEEL CORPORATION

Inventor： Yuki SUZUKI ,  Soshi FUJITA ,  Jun MAKI ,  Kazuhisa KUSUMI ,  Masahiro FUDA

IPC: B21D35/00 ,  C23C2/12

CPC classification number: B21D35/007 ,  C23C2/12

Abstract: A plated steel sheet for hot stamping according to one aspect of the present invention includes a steel sheet, a plating layer formed on either surface or both surfaces of the steel sheet and having an Al content of 60 mass % or more, and a surface film layer formed on the plating layer. A thickness t of the plating layer is 10 to 60 μm. An average crystal grain diameter of the plating layer in a thickness range from an interface between the plating layer and the surface film layer to a position at ⅔ of the thickness t is 2t/3 or less and 15.0 μm or less. A surface film layer contains particles containing one or more elements selected from A group elements consisting of Sc, V, Mn, Fe, Co, Ce, Nb, Mo, and W. A total content of the A group elements is 0.01 to 10.0 g/m2. An average grain diameter of the particles containing the A group elements is 0.05 to 3.0 μm.

公开(公告)号：US20230416888A1

公开(公告)日：2023-12-28

申请号：US18463110

申请日：2023-09-07

Applicant: NIPPON STEEL CORPORATION

Inventor： Jun MAKI ,  Soshi FUJITA ,  Toyomitsu NAKAMURA

IPC: C22C38/54 ,  B23K11/00 ,  B23K35/02 ,  B23K35/30 ,  C21D9/08 ,  C22C38/00 ,  C22C38/02 ,  C22C38/06 ,  C22C38/42 ,  C22C38/44 ,  C22C38/48 ,  C22C38/50 ,  C25D3/44 ,  C25D7/04

CPC classification number: C22C38/54 ,  B23K11/002 ,  B23K35/0261 ,  B23K35/3053 ,  C21D9/08 ,  C22C38/001 ,  C22C38/002 ,  C22C38/02 ,  C22C38/06 ,  C22C38/42 ,  C22C38/44 ,  C22C38/48 ,  C22C38/50 ,  C25D3/44 ,  C25D7/04 ,  B23K2103/04

Abstract: An Al plated electric resistance welded steel pipe for hardening use suppressing the formation of scale to the inside of the plating layer while performing hot forming and an Al plated hollow member using that Al plated electric resistance welded steel pipe, wherein the Al plated electric resistance welded steel pipe for hardening use is comprised of a base material made of a tubular steel plate and having a predetermined chemical composition and an electric resistance welded zone provided at a seam portion of the steel plate and extending in a longitudinal direction of the steel plate, the base material is further provided with an intermetallic compound layer positioned on the surface of the steel plate and including an Al—Fe—Si-based intermetallic compound and an Al plating layer positioned on the surface of the intermetallic compound layer and containing Al and Si, and 70×X/D≤Y/t≤30 is satisfied, wherein X (μm) is a thickness of the intermetallic compound layer, Y (μm) is a thickness of the Al plating layer, t (mm) is a pipe thickness of the steel pipe, and D (mm) is an outside diameter of the steel pipe.

公开(公告)号：US20230116894A1

公开(公告)日：2023-04-13

申请号：US17914389

申请日：2020-05-18

Applicant: NIPPON STEEL CORPORATION

Inventor： Michiko KONNO ,  Jun MAKI ,  Shinichi YAMAGUCHI ,  Soshi FUJITA

IPC: C21D8/02 ,  C22C38/54 ,  C22C38/44 ,  C22C38/42 ,  C22C38/50 ,  C22C38/06 ,  C22C38/04 ,  C23C28/00 ,  C21D9/46

Abstract: Provided is a hot stamped body comprising a steel base material, an Al-plating layer formed on at least one surface of the steel base material, a coating formed on the Al-plating layer and containing ZnO particles and CeO2 particles having an average particle size smaller than an average particle size of the ZnO particles, and a Zn- and Al-containing complex oxide layer formed between the Al-plating layer and the coating. Further, provided is a method for producing a hot stamped body comprising forming an Al-plating layer on at least one side of a steel sheet, coating a surface of the Al-plating layer with an aqueous solution containing ZnO particles and CeO2 particles, then heating it to form a coating containing ZnO particles and CeO2 particles on the Al-plating layer, and hot pressing the steel sheet. Further, provided is an Al-plated steel sheet comprising a steel base material, an Al-plating layer formed on at least one surface of the steel base material, and a coating formed on the Al-plating layer and containing ZnO particles and CeO2 particles having an average particle size smaller than an average particle size of the ZnO particles.

公开(公告)号：US20220356547A1

公开(公告)日：2022-11-10

申请号：US17619268

申请日：2020-04-16

Applicant: NIPPON STEEL CORPORATION

Inventor： Kohei TOKUDA ,  Mamoru SAITO ,  Jun MAKI ,  Takuya MITSUNOBU ,  Yasuto GOTO

IPC: C22C18/04 ,  B32B15/01 ,  C23C2/06 ,  C23C2/40

Abstract: A hot-dip coated steel product including: a steel product; and a coating layer including a Zn—Al—Mg alloy layer disposed on a surface of the steel product, in which the Zn—Al—Mg alloy layer includes a Zn phase, an Al phase, and a MgZn2 phase, and contains a Mg—Sn intermetallic compound phase in the Zn phase, and the coating layer has a chemical composition satisfying a predetermined average composition, a total area proportion of the Al phase and the MgZn2 phase is 70% or more, an area proportion of the Zn phase is 30% or less, an average value of cumulative circumferential lengths of the Al phase is less than 88 mm/mm2, and a total frequency in number of the Al phase having a circumferential length of 50 μm or more is less than 100.

公开(公告)号：US20220316022A1

公开(公告)日：2022-10-06

申请号：US17440646

申请日：2020-04-17

Applicant: NIPPON STEEL CORPORATION

Inventor： Hiroyasu FUJII ,  Jun MAKI ,  Kazutoshi TAKEDA ,  Hiroyuki MIMURA ,  Yusuke KANTO ,  Shuichi YAMAZAKI

IPC: C21D8/12 ,  H01F1/18

Abstract: A non-oriented electrical steel sheet according to one embodiment of this invention includes a base metal steel sheet and a composite coating film composed of a Zn-containing phosphate and an organic resin, the composite coating film being formed on a surface of the base metal steel sheet. A molar ratio of Zn to all metal components in the composite coating film is 10 mol % or more, and after the non-oriented electrical steel sheet is boiled for 20 minutes in boiled distilled water, an amount of soluble Zn in the distilled water is 1.0 mg/m2 or more. The method for determining the amount of soluble Zn is in accordance with JIS K 0102: 2016 “Testing Methods for Industrial Wastewater”, 53.3 “ICP Emission Spectroscopy”.

公开(公告)号：US20220152983A1

公开(公告)日：2022-05-19

申请号：US17435613

申请日：2020-04-16

Applicant: NIPPON STEEL CORPORATION

Inventor： Takuya MITSUNOBU ,  Jun MAKI ,  Hiroshi TAKEBAYASHI ,  Takehiro TAKAHASHI ,  Kohei TOKUDA

IPC: B32B15/01 ,  C22C38/04 ,  C22C38/02 ,  C22C18/00 ,  C23C2/06 ,  C23C2/20 ,  C23C2/28 ,  C23C2/40

Abstract: A plated steel includes: a steel; and a plating layer that is provided on a surface of the steel, in which the plating layer includes, by mass %, Al: 5.00% to 35.00%, Mg: 2.50% to 13.00%. Fe: 5.00% to 40.00%, Si: 0% to 2.00%, Ca: 0% to 2.00%, and a remainder of Zn and impurities, and in a cross section of the plating layer, the area fraction of a Zn solid-solution Fe2Al5 phase in which 5% or more of Zn is solid-soluted is 10% to 60% and the area fraction of a MgZn2 phase is 10% to 90%.

公开(公告)号：US20220119921A1

公开(公告)日：2022-04-21

申请号：US17427544

申请日：2020-04-16

Applicant: NIPPON STEEL CORPORATION

Inventor： Takuya MITSUNOBU ,  Jun MAKI ,  Hiroshi TAKEBAYASHI ,  Takehiro TAKAHASHI ,  Kohei TOKUDA

IPC: C22C18/04 ,  C22C38/02 ,  C23C2/28 ,  C23C2/06 ,  B32B15/01 ,  C22C38/04 ,  C23C2/40

Abstract: A plated steel sheet having excellent chemical convertibility includes: a steel; and a plating layer that is provided on a surface of the steel, in which the plating layer includes, by mass %, Al: 5.00% to 35.00%, Mg: 2.50% to 13.00%, Fe: 5.00% to 35.00%, Si: 0% to 2.00%, Ca: 0.03% to 2.00%, and a remainder consisting of Zn and impurities, and in a surface of the plating layer, the area fraction of a Fe—Al phase is 0% to 30%, the area fraction of a rod-like lamellar structure of Zn and MgZn2 is 5% to 90%, the area fraction of a massive MgZn2 phase is 10% to 70%, and the area fraction of a remainder is 10% or less.

公开(公告)号：US20220010450A1

公开(公告)日：2022-01-13

申请号：US17291846

申请日：2019-12-20

Applicant: NIPPON STEEL CORPORATION

Inventor： Takehiro TAKAHASHI ,  Yasuto GOTO ,  Jun MAKI

IPC: C25D5/14

Abstract: A Ni-coated steel sheet according to an aspect of the present invention includes: a base steel sheet; a diffusion alloy layer disposed on the base steel sheet; and a Ni-coated layer disposed on the diffusion alloy layer, in which a depth-hardness curve obtained by continuously performing Vickers hardness measurement on a cross section perpendicular to a rolled surface of the base steel sheet from a surface layer of the Ni-coated layer to the base steel sheet using a nanoindenter includes, in the diffusion alloy layer, a peak indicating a Vickers hardness of 1.50 times or more a Vickers hardness of the surface layer of the Ni-coated layer.