公开(公告)号：US20210340650A1

公开(公告)日：2021-11-04

申请号：US17280509

申请日：2019-09-20

Applicant: POSCO

Inventor： Il-Jeong PARK ,  Myung-Soo KIM ,  Suk-Kyu LEE

IPC: C22C38/06 ,  C23C2/06 ,  C23C2/40 ,  C23C2/26 ,  C21D9/46 ,  C23C2/02

Abstract: Provided is a highly corrosion-resistant plated steel sheet having plating adhesion and resistance to liquid metal embrittlement. A highly corrosion-resistant plated steel sheet comprises a base steel sheet and a plated layer, which sequentially comprises an Fe—Al alloy layer and an MgZn2 layer from an interface with the base steel sheet.

公开(公告)号：US11148395B2

公开(公告)日：2021-10-19

申请号：US16480428

申请日：2018-01-10

Applicant: JFE STEEL CORPORATION

Inventor： Masaki Koba ,  Yusuke Fushiwaki ,  Yasunobu Nagataki

IPC: B32B15/01 ,  C22C38/14 ,  C22C38/12 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/00 ,  C21D9/46 ,  C21D8/02 ,  C21D6/00 ,  C23C2/02 ,  C23C2/28 ,  C23C2/40 ,  C23C2/06 ,  C23C2/12 ,  C23C28/02 ,  C23C30/00 ,  B32B15/04 ,  C23C28/00 ,  B32B15/18 ,  C21D1/76

Abstract: There is provided a high-strength hot-dipped steel sheet having excellent coating adhesion and a method for manufacturing the steel sheet. The steel sheet has a chemical composition, and a coating layer is disposed on the steel sheet. The chemical composition includes, by mass %, C: 0.02% or greater and 0.30% or less, Si: 0.01% or greater and 2.0% or less, Mn: 0.2% or greater and 3.0% or less, P: 0.08% or less, S: 0.02% or less, and Al: 0.001% or greater and 0.40% or less, with the balance being Fe and incidental impurities. The coating layer has a coating weight per side of 30 to 90 g/m2 and contains exfoliated base steel in an amount of 0.3 to 1.5 g/m2.

公开(公告)号：US20210301364A1

公开(公告)日：2021-09-30

申请号：US17262237

申请日：2019-07-10

Applicant: Muhr und Bender KG

Inventor： Stefan Pohl ,  Elisabeth Danger ,  Thorsten Labudde ,  Jürgen Butzkamm

IPC: C21D9/46 ,  C23C2/02 ,  C23C2/12 ,  C23C2/28 ,  C22C38/58 ,  C22C38/54 ,  C22C38/50 ,  C22C38/06 ,  C22C38/02 ,  C22C38/00 ,  C22C38/42 ,  C22C38/48 ,  C22C38/44 ,  C22C38/46 ,  C21D1/673 ,  C21D6/00 ,  C21D8/02

Abstract: Producing a hardened steel product can comprise providing a steel substrate of a hardenable steel; coating the steel substrate with an aluminum precoating, wherein the precoating is applied to the steel substrate with a thickness of at least 34 μm; flexible rolling the pre-coated steel substrate to produce a variable thickness along the length of the precoated steel substrate, wherein the precoating is rolled out to a reduced first thickness of less than 33 μm in thinner first portions and to a reduced second thickness thicker than the reduced first thickness in thicker second portions; working out a blank from the flexibly rolled steel substrate; heating the blank to austenitizing temperature, wherein diffusion processes take place between the base material and the precoating; and hot forming the heated blank, wherein the heated blank is formed and rapidly cooled such that a hardened steel product with coating is produced.

公开(公告)号：US20210292915A1

公开(公告)日：2021-09-23

申请号：US17253515

申请日：2019-07-03

Applicant: Bayerische Motoren Werke Aktiengesellschaft

Inventor： Clemens BERGMANN

IPC: C23F13/14 ,  C23C2/02 ,  C25F3/24 ,  C23F3/04 ,  C23C2/06

Abstract: A method for coating a motor vehicle part includes coating and subsequently painting. In the coating, a motor vehicle bodyshell part is coated with a metallic zinc coat as cathodic corrosion protection. In the subsequent painting, the coated motor vehicle bodyshell part is painted. The motor vehicle bodyshell part is chemically polished and/or electrochemically polished prior to the coating with the metallic zinc coat.

公开(公告)号：US11091817B2

公开(公告)日：2021-08-17

申请号：US16324975

申请日：2017-08-29

Applicant: JFE Steel Corporation

Inventor： Lingling Yang ,  Noriaki Kohsaka ,  Tatsuya Nakagaito ,  Yoshimasa Funakawa

IPC: C21D8/02 ,  C21D9/46 ,  C22C38/14 ,  C22C38/60 ,  C21D9/56 ,  C22C38/00 ,  C22C38/06 ,  C22C38/08 ,  C22C38/10 ,  C22C38/12 ,  C22C38/16 ,  C22C38/22 ,  C22C38/28 ,  C22C38/32 ,  C22C38/34 ,  C22C38/38 ,  C23C2/02 ,  C23C2/06 ,  C23C2/40

Abstract: Provided are a high-strength steel sheet having high strength of a yield strength of 550 MPa or more and a method for manufacturing the same.
The high-strength steel sheet has a specified chemical composition and a microstructure, where observed in a cross section in a thickness direction perpendicular to a rolling direction, including a martensite phase having a volume fraction of 50% to 80%, and a ferrite phase having an average grain diameter of 13 μm or less, wherein a volume fraction of ferrite grains having an aspect ratio of 2.0 or less with respect to the whole ferrite phase is 70% or more, and wherein an average length in a longitudinal direction (in a width direction of the steel sheet) of the ferrite grains is 20 μm or less, and a yield strength (YP) of 550 MPa or more.

公开(公告)号：US11078564B2

公开(公告)日：2021-08-03

申请号：US16062945

申请日：2016-12-22

Applicant: POSCO

Inventor： Sang-Heon Kim

IPC: B32B15/01 ,  C23C2/06 ,  C23C2/40 ,  C22C18/04 ,  C22C38/00 ,  C22C18/00 ,  C23C2/26 ,  C23C2/02 ,  C21D9/46

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 μm 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.

公开(公告)号：US11078552B2

公开(公告)日：2021-08-03

申请号：US16082158

申请日：2017-01-30

Applicant: JFE STEEL CORPORATION

Inventor： Fusae Shiimori ,  Shinjiro Kaneko ,  Yasunobu Nagataki

IPC: C21D8/02 ,  C21D9/46 ,  C22C38/06 ,  C23C2/06 ,  C23C2/28 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/38 ,  C23C2/12 ,  C23C2/02 ,  C22C38/08 ,  C22C38/12 ,  C22C38/14 ,  C22C38/16 ,  C22C38/22

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 μm 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.

公开(公告)号：US11066721B2

公开(公告)日：2021-07-20

申请号：US16065419

申请日：2016-11-08

Applicant: JFE STEEL CORPORATION

Inventor： Masaki Koba ,  Yoshitsugu Suzuki ,  Hiroyuki Masuoka

IPC: C21D6/00 ,  C21D8/02 ,  C21D9/46 ,  C22C38/14 ,  C22C38/12 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/00 ,  C23C2/28 ,  C23C2/40 ,  B32B15/01 ,  C23C2/02 ,  C23C2/06 ,  C23C2/26 ,  C23G1/08 ,  C23C28/00 ,  C23C2/04 ,  C23C28/02 ,  B32B15/18 ,  C23C30/00 ,  B32B7/04 ,  C21D8/04 ,  B32B15/04 ,  B32B7/02 ,  C23G1/00

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 μm or less on the surface of the steel sheet, and a tensile strength of 590 MPa or more.

公开(公告)号：US20210180151A1

公开(公告)日：2021-06-17

申请号：US17178518

申请日：2021-02-18

Applicant: JFE Steel Corporation

Inventor： Katsutoshi Takashima ,  Yoshimasa Funakawa

IPC: C21D9/46 ,  C22C38/58 ,  C22C38/38 ,  C22C38/14 ,  C22C38/12 ,  C22C38/04 ,  C21D8/02 ,  C22C38/16 ,  C22C38/46 ,  C22C38/40 ,  C21D6/00 ,  C22C38/44 ,  C22C38/42 ,  C22C38/28 ,  C22C38/48 ,  C22C38/18 ,  C22C38/54 ,  C22C38/08 ,  C23C2/12 ,  B32B15/01 ,  B32B15/04 ,  C23C28/02 ,  C23C2/02 ,  C23C30/00 ,  B32B15/18 ,  C23C2/04 ,  C22C38/00 ,  C22C38/02 ,  C22C38/06 ,  C22C38/20 ,  C22C38/22 ,  C22C38/24 ,  C22C38/26 ,  C22C38/32 ,  C22C38/50 ,  C23C2/06 ,  C23C2/28 ,  C23C2/40

Abstract: A method for producing a hot-rolled steel sheet, a method for producing a cold-rolled full-hard steel sheet, and a method for producing a heat-treated sheet are provided herein. The methods comprising hot rolling a steel material of a composition comprising, in mass %, C: 0.05 to 0.12%, Si: 0.80% or less, Mn: 1.30 to 2.10%, P: 0.001 to 0.050%, S: 0.005% or less, Al: 0.01 to 0.10%, N: 0.010% or less, one or more selected from Cr in an amount of 0.05 to 0.50%, and Mo in an amount of 0.05 to 0.50%, one or more selected from Ti in an amount of 0.01 to 0.10%, Nb in an amount of 0.01 to 0.10%, and V in an amount of 0.01 to 0.10%, and the balance Fe and unavoidable impurities.

公开(公告)号：US11021776B2

公开(公告)日：2021-06-01

申请号：US15803401

申请日：2017-11-03

Applicant: NUCOR CORPORATION

Inventor： Weiping Sun

IPC: C21D8/00 ,  C22C38/16 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/00 ,  C23C2/06 ,  C22C38/12 ,  C21D8/02 ,  C23C2/28 ,  C23C2/40 ,  C23C2/02

Abstract: A hot rolled, ultra-high strength, complex metallographic structured or multi-phase structured steel that improves formability during stamping or forming process, while possessing one or more of the following properties: excellent castability, rollability and coatability, excellent structural performance, excellent stretch formability, excellent stretch flangeability, excellent dent resistance, excellent durability, excellent impact performance, excellent intrusion and crash resistance without the purposeful addition of boron.