公开(公告)号：US20240344165A1

公开(公告)日：2024-10-17

申请号：US18681807

申请日：2021-08-27

Applicant: NIPPON STEEL CORPORATION

Inventor： Yasuhiro ITO ,  Mai NAGANO ,  Hiroyuki KAWATA ,  Satoshi HIRONAKA

IPC: C21D9/46 ,  C21D8/02 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C23C2/06 ,  C23C2/40

CPC classification number: C21D9/46 ,  C21D8/0226 ,  C21D8/0236 ,  C21D8/0273 ,  C22C38/001 ,  C22C38/002 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C23C2/06 ,  C23C2/40

Abstract: Adopted are a steel sheet contains, as a chemical composition, by mass %, C: 0.040% to 0.105%, Mn: 1.00% to 2.30%, Si: 0.005% to 1.500%, Al: 0.005% to 0.700%, P: 0.100% or less, S: 0.0200% or less, N: 0.0150% or less, O: 0.0100% or less, and a remainder: Fe and impurities, in which ΔC that is calculated from C20, which is a C content at a 20 μm depth position from a surface, C60, which is a C content at a 60 μm depth position from the surface, and the following expression (1) is in a range of 0.20 to 0.90 mass %/mm, and a press-formed article that is obtained by press-forming the steel sheet.








Δ
⁢
C

=


(


C
60

-

C

2
⁢
0



)

/

(
0.04
)






(
1
)

公开(公告)号：US12116673B2

公开(公告)日：2024-10-15

申请号：US17347868

申请日：2021-06-15

Applicant: ArcelorMittal

Inventor： Luc Diez ,  Clémence Filou ,  Gunhild Föjer ,  Manel Ben Saad

IPC: C23C2/06 ,  C23C2/26 ,  C23C2/36 ,  C23C22/34 ,  C23C22/78 ,  C23C22/82

CPC classification number: C23C22/78 ,  C23C2/06 ,  C23C2/26 ,  C23C2/36 ,  C23C22/34 ,  C23C22/82

Abstract: A process for the manufacture of a pre-painted sheet. The process includes supplying a steel substrate, depositing a metallic coating on at least one face by hot-dipping of the substrate in a bath including 4.4% to 5.25% by weight aluminum and 0.3% to 0.56% by weight magnesium. The rest of the bath includes exclusively zinc, unavoidable impurities resulting from the process and optionally one or more additional elements including Si, Ti, Ca, Mn, La, Ce and Bi. The content by weight of each additional element in the metallic coating is less than 0.3% and the presence of nickel is excluded. The process further includes solidifying the metallic coating, surface preparation of the metallic coating and painting of the metallic coating. The present invention further provides a pre-painted sheet.

公开(公告)号：US20240326399A1

公开(公告)日：2024-10-03

申请号：US18353843

申请日：2023-07-17

Applicant: POSCO CO., LTD

Inventor： Tae-Jin SONG ,  Min-Seo KOO

IPC: B32B38/00 ,  B23K20/04 ,  B23K20/227 ,  B23K20/24 ,  B23K31/02 ,  B23K101/16 ,  B23K101/18 ,  B23K103/04 ,  B23K103/18 ,  B32B15/01 ,  B32B15/04 ,  B32B15/18 ,  C21D1/18 ,  C21D1/25 ,  C21D8/02 ,  C21D8/04 ,  C21D9/48 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/08 ,  C22C38/12 ,  C22C38/14 ,  C22C38/18 ,  C22C38/22 ,  C22C38/26 ,  C22C38/28 ,  C22C38/32 ,  C22C38/34 ,  C22C38/38 ,  C22C38/40 ,  C22C38/44 ,  C22C38/48 ,  C22C38/50 ,  C22C38/54 ,  C23C2/02 ,  C23C2/06 ,  C23C2/12 ,  C23C2/18 ,  C23C2/34 ,  C23C2/40 ,  C23C30/00

CPC classification number: B32B38/004 ,  B23K20/04 ,  B23K20/227 ,  B23K20/24 ,  B23K31/02 ,  B32B15/01 ,  B32B15/011 ,  B32B15/015 ,  B32B15/04 ,  B32B15/043 ,  B32B15/18 ,  C21D1/18 ,  C21D8/0226 ,  C21D8/0236 ,  C21D8/041 ,  C21D8/0426 ,  C21D8/0436 ,  C21D8/0463 ,  C21D8/0473 ,  C21D9/48 ,  C22C38/001 ,  C22C38/002 ,  C22C38/02 ,  C22C38/06 ,  C22C38/08 ,  C22C38/12 ,  C22C38/14 ,  C22C38/18 ,  C22C38/22 ,  C22C38/26 ,  C22C38/28 ,  C22C38/32 ,  C22C38/34 ,  C22C38/38 ,  C22C38/40 ,  C22C38/44 ,  C22C38/48 ,  C22C38/50 ,  C22C38/54 ,  C23C2/02 ,  C23C2/022 ,  C23C2/024 ,  C23C2/026 ,  C23C2/06 ,  C23C2/12 ,  C23C2/18 ,  C23C2/34 ,  C23C2/40 ,  C23C30/00 ,  C23C30/005 ,  B23K2101/16 ,  B23K2101/18 ,  B23K2103/04 ,  B23K2103/18 ,  B32B15/012 ,  B32B15/013 ,  B32B2038/0048 ,  B32B2250/03 ,  B32B2250/40 ,  B32B2307/536 ,  B32B2307/552 ,  B32B2307/72 ,  C21D1/25 ,  C21D2211/001 ,  C21D2211/002 ,  C21D2211/004 ,  C21D2211/005 ,  C21D2211/008 ,  C21D2251/02 ,  C22C38/04 ,  Y10T428/12451 ,  Y10T428/12493 ,  Y10T428/12729 ,  Y10T428/12757 ,  Y10T428/12799 ,  Y10T428/12958 ,  Y10T428/12965 ,  Y10T428/12972 ,  Y10T428/12979 ,  Y10T428/12993 ,  Y10T428/2495 ,  Y10T428/24959 ,  Y10T428/24967 ,  Y10T428/24992 ,  Y10T428/26 ,  Y10T428/263 ,  Y10T428/264 ,  Y10T428/265

Abstract: A method of manufacturing a low-density clad steel sheet, including: preparing a base material, a lightweight steel sheet including C: 0.3 to 1.0%, Mn: 4.0 to 16.0%, Al: 4.5 to 9.0%, and Fe; preparing cladding materials, each being martensitic carbon steel including C: 0.1 to 0.45%, Mn: 0.1 to 3.0%, and Fe; disposing the base material between the cladding materials to obtain a laminate; welding an edge of the laminate, and heating the welded laminate to 1050 to 1350° C.; finish-rolling the heated laminate to 750 to 1050° C. with a rolling reduction ratio of 30% or more in a first pass, to obtain a hot-rolled steel sheet; coiling the hot-rolled steel sheet at 400 to 700° C.; applying a cold-reduction ratio of 35 to 90% to obtain a cold-rolled steel sheet; and annealing the cold-rolled steel sheet at 550° C. or higher and A3+200° C. or lower of the cladding materials.

公开(公告)号：US12104255B2

公开(公告)日：2024-10-01

申请号：US17866628

申请日：2022-07-18

Applicant: ArcelorMittal

Inventor： Tiago Machado Amorim ,  Christian Allely ,  Gregory Leuillier

IPC: C23C2/12 ,  C21D1/673 ,  C21D8/00 ,  C21D8/02 ,  C23C2/06 ,  C23C2/26 ,  C23C2/28 ,  C22C21/10 ,  C22F1/053 ,  C23C22/07

CPC classification number: C23C2/12 ,  C21D1/673 ,  C21D8/0257 ,  C23C2/06 ,  C23C2/26 ,  C23C2/261 ,  C23C2/28 ,  C23C2/29 ,  C21D2211/002 ,  C21D2211/005 ,  C21D2211/008

Abstract: A hardened part coated with a phosphatable coating is provided. The part is made by a method that includes providing a steel sheet pre-coated with a metallic coating including from 4.0 to 20.0% by weight of zinc, from 1.0 to 3.5% by weight of silicon, optionally from 1.0 to 4.0% by weight of magnesium, and optionally additional elements chosen from Pb, Ni, Zr, or Hf, the content by weight of each additional element being less than 0.3% by weight, the balance being aluminum and unavoidable impurities and residuals elements. The steel sheet is cut to obtain a blank, the blank is thermally treated at a temperature between 840 and 950° C. to obtain a fully austenitic microstructure in the steel, the blank is transferred into a press tool and hot-formed to obtain a part. The part is cooled to obtain a martensitic or martensitic-bainitic microstructure or made of at least 75% of equiaxed ferrite, from 5 to 20% of martensite and bainite in amount less than or equal to 10%.

公开(公告)号：US20240318287A1

公开(公告)日：2024-09-26

申请号：US18579575

申请日：2022-03-18

Applicant: JFE STEEL CORPORATION

Inventor： Sho HIGUCHI ,  Yoshiyasu KAWASAKI ,  Tatsuya NAKAGAITO ,  Takako YAMASHITA ,  Tomomi KANAZAWA ,  Shunsuke YAMAMOTO

IPC: C22C38/04 ,  C21D6/00 ,  C21D8/02 ,  C22C38/02 ,  C22C38/06 ,  C23C2/06 ,  C23C2/28

CPC classification number: C22C38/04 ,  C21D6/005 ,  C21D8/0205 ,  C21D8/0226 ,  C21D8/0236 ,  C21D8/0273 ,  C22C38/02 ,  C22C38/06 ,  C23C2/06 ,  C23C2/29 ,  C21D2211/001 ,  C21D2211/002 ,  C21D2211/005 ,  C21D2211/008

Abstract: A galvanized steel sheet combining high strength with excellent formability, specifically, excellent ductility, hole expansion formability, local ductility, strain hardenability, and dimensional accuracy when forming a member. The base steel sheet has a defined chemical composition and a steel microstructure as follows: ferrite area ratio: 35.0% or more and 95.0% or less, bainitic ferrite area ratio: 1.0% or more and 40.0% or less, tempered martensite area ratio: 50.0% or less (including 0%), retained austenite area ratio: 1.5% or more, fresh martensite area ratio: 20.0% or less (including 0 %), SBF+STM+2×SMA: 10.0% or more and less than 65.0%, SBF+STM: 3.0 % or more and 60.0% or less, SMA1/SMA: 0.40 or less, IDR [% Cγ]: 0.16% or more, and tensile strength: 590 MPa or more and less than 980 MPa.

公开(公告)号：US12054829B2

公开(公告)日：2024-08-06

申请号：US17762533

申请日：2020-09-24

Applicant: POSCO ,  STEEL & CONVERGENCE TECHNOLOGY RESEARCH ASSOCIATION ,  POSCO COATED & COLOR STEEL CO., LTD.

Inventor： Sung-Joo Kim ,  Kyung-Kwan Park ,  Moon-Hi Hong ,  Heung-Yun Kim ,  Tae-Yeul Park ,  Myung-Soo Kim ,  Il-Ryoung Sohn ,  Tae-Chul Kim ,  Dae-Young Kang

IPC: C23C2/06 ,  B32B15/01 ,  B32B15/04 ,  B32B15/18 ,  C21D7/06 ,  C22C18/00 ,  C22C18/04 ,  C23C2/00 ,  C23C2/02 ,  C23C2/28 ,  C23C2/40 ,  C23C28/00 ,  C23C28/02 ,  C23C30/00

CPC classification number: C23C2/06 ,  B32B15/01 ,  B32B15/013 ,  B32B15/04 ,  B32B15/043 ,  B32B15/18 ,  C21D7/06 ,  C22C18/00 ,  C22C18/04 ,  C23C2/0035 ,  C23C2/02 ,  C23C2/285 ,  C23C2/29 ,  C23C2/40 ,  C23C28/02 ,  C23C28/021 ,  C23C28/023 ,  C23C28/025 ,  C23C28/322 ,  C23C28/3225 ,  C23C30/00 ,  C23C30/005 ,  Y10T428/12951 ,  Y10T428/12958 ,  Y10T428/12972 ,  Y10T428/12979 ,  Y10T428/12993 ,  Y10T428/24942 ,  Y10T428/24983 ,  Y10T428/263 ,  Y10T428/265

Abstract: Provided are a plated steel sheet and a method for manufacturing same, the plated steel sheet comprising: a base steel sheet; a Zn—Mg—Al plating layer provided on at least one surface of the base steel sheet; and an Fe—Al inhibition layer provided between the base steel sheet and the Zn—Mg—Al plating layer. The plating layer comprises, by weight %, 4 to 10% of Mg and 5.1-25% of Al and the remainder being Zn and unavoidable impurities with respect to components not including iron (Fe) diffused from the base steel sheet. The plating layer comprises a 24-50% MgZn2 phase in phase fraction. In the MgZn2 phase, an Al single phase is present in the ratio of 1-30% relative to the cross-sectional area of the total MgZn2 phase.

公开(公告)号：US20240254585A1

公开(公告)日：2024-08-01

申请号：US18293772

申请日：2022-08-01

Applicant: POSCO CO., LTD

Inventor： Tae-Jin SONG ,  Won HUR

IPC: C21D9/46 ,  C21D1/18 ,  C21D6/00 ,  C21D8/02 ,  C22C38/00 ,  C22C38/02 ,  C22C38/06 ,  C22C38/22 ,  C22C38/26 ,  C22C38/28 ,  C22C38/32 ,  C22C38/38 ,  C23C2/06

CPC classification number: C21D9/46 ,  C21D1/18 ,  C21D6/002 ,  C21D6/005 ,  C21D6/008 ,  C21D8/0205 ,  C21D8/0226 ,  C21D8/0263 ,  C21D8/0278 ,  C22C38/001 ,  C22C38/002 ,  C22C38/02 ,  C22C38/06 ,  C22C38/22 ,  C22C38/26 ,  C22C38/28 ,  C22C38/32 ,  C22C38/38 ,  C21D2211/001 ,  C21D2211/002 ,  C21D2211/005 ,  C21D2211/008 ,  C23C2/06

Abstract: Provided are a hot-rolled steel sheet having excellent formability and a manufacturing method therefore. The steel sheet includes: carbon (C): 0.05 to 0.17%, silicon (Si): 0.01 to 1.5%, manganese (Mn): 1.5 to 3.0%, aluminum (Al): 0.01 to 0.1%, chromium (Cr): 2.0% or less (including 0%), molybdenum (Mo): 2.0% or less (including 0%), titanium (Ti): 0.01 to 0.15%, phosphorus (P): 0.001 to 0.05%, sulfur (S): 0.0001 to 0.05%, nitrogen (N): 0.0001 to 0.02%, with a balance of Fe and other unavoidable impurities, satisfies: (1.5×[Si]+1.2×[Cr]+0.7×[Mo]+8.0×[Ti])/[C]>20 where each element refers to a weight content, and a microstructure including 70 to 90% of acicular ferrite or bainitic ferrite by area fraction, as a matrix structure, and one or more second phases among low-temperature bainite, tempered martensite, and MA phase.

公开(公告)号：US20240240299A1

公开(公告)日：2024-07-18

申请号：US18622583

申请日：2024-03-29

Applicant: POSCO CO., LTD

Inventor： Ki-Cheol KANG ,  Sang-Ho UHM ,  Chang-Woon JEE ,  Yeon-Chae JEONG ,  Kwang-Tai MIN

IPC: C23C2/06 ,  C21D8/02 ,  C21D9/46 ,  C22C38/00 ,  C22C38/02 ,  C22C38/06 ,  C22C38/22 ,  C22C38/24 ,  C22C38/26 ,  C22C38/32 ,  C22C38/38 ,  C23C2/02 ,  C23C2/28 ,  C23C2/40

CPC classification number: C23C2/06 ,  C21D8/0205 ,  C21D8/0226 ,  C21D8/0236 ,  C21D9/46 ,  C22C38/001 ,  C22C38/002 ,  C22C38/008 ,  C22C38/02 ,  C22C38/06 ,  C22C38/22 ,  C22C38/24 ,  C22C38/26 ,  C22C38/32 ,  C22C38/38 ,  C23C2/02 ,  C23C2/0222 ,  C23C2/0224 ,  C23C2/024 ,  C23C2/28 ,  C23C2/40

Abstract: A welded member includes: a first steel sheet including a base steel sheet and a zinc-based plating layer formed on a surface of the base steel sheet; and a second steel sheet spot-welded on the first steel sheet and facing the zinc-based plating layer of the first steel sheet, a spot-welded zone being formed between the first steel sheet and the second steel sheet. A surface layer of the base steel sheet has a decarburization ratio of 30% or more. The decarburization ratio is represented by equation: Decarburization ratio (%) of surface layer=(1−average carbon concentration in surface layer/bulk carbon concentration)*100 where the surface layer refers to a region of the base steel sheet from the surface thereof to a depth of 35 μm. A shoulder portion of the spot-welded zone includes a B-type crack having a length of 100 μm or less, and no C-type crack.

公开(公告)号：US20240240278A1

公开(公告)日：2024-07-18

申请号：US18288201

申请日：2021-04-27

Applicant: NIPPON STEEL CORPORATION

Inventor： Takuya MITSUNOBU ,  Keitaro MATSUDA ,  Jun MAKI ,  Takehiro TAKAHASHI ,  Hiroshi TAKEBAYASHI

IPC: C21D9/46 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C23C2/06 ,  C23C2/40

CPC classification number: C21D9/46 ,  C22C38/001 ,  C22C38/002 ,  C22C38/02 ,  C22C38/04 ,  C23C2/06 ,  C23C2/40

Abstract: A steel sheet comprising, by mass %, C: 0.05 to 0.40%, Si: 0.2 to 3.0%, and Mn: 0.1 to 5.0%, wherein a surface layer of the steel sheet contains granular oxides, an average grain size of the granular oxides is 300 nm or less, a number density of granular oxides is 4.0/μm2 or more, the steel sheet comprises an Si—Mn depleted layer having a thickness of 3.0 μm or more from the surface of the steel sheet, and Si and Mn contents of the Si—Mn depleted layer not containing oxides at the ½ position of the thickness are respectively less than 10% of the Si and Mn contents at the sheet thickness center part of the steel sheet, and a plated steel sheet using the same are provided.

公开(公告)号：US20240229212A1

公开(公告)日：2024-07-11

申请号：US18562665

申请日：2022-04-21

Applicant: NIPPON STEEL CORPORATION

Inventor： Taihei KANETO ,  Takashi OKE ,  Nayuta KAWAZU ,  Atsushi KOMURO ,  Tomohiro MIYASHITA

IPC: C23C2/06 ,  C21D1/74 ,  C21D6/00 ,  C21D8/02 ,  C21D9/46 ,  C22C18/00 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/08 ,  C22C38/10 ,  C22C38/12 ,  C22C38/14 ,  C22C38/16 ,  C22C38/26 ,  C22C38/28 ,  C22C38/32 ,  C22C38/42 ,  C22C38/44 ,  C22C38/46 ,  C22C38/48 ,  C22C38/50 ,  C22C38/52 ,  C22C38/54 ,  C22C38/56 ,  C22C38/60 ,  C23C2/28 ,  C23C2/40

CPC classification number: C23C2/06 ,  C21D1/74 ,  C21D6/001 ,  C21D6/002 ,  C21D6/004 ,  C21D6/005 ,  C21D6/007 ,  C21D6/008 ,  C21D8/0205 ,  C21D8/0226 ,  C21D8/0236 ,  C21D8/0263 ,  C21D8/0278 ,  C21D9/46 ,  C22C18/00 ,  C22C38/001 ,  C22C38/002 ,  C22C38/004 ,  C22C38/005 ,  C22C38/008 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/08 ,  C22C38/10 ,  C22C38/12 ,  C22C38/14 ,  C22C38/16 ,  C22C38/26 ,  C22C38/28 ,  C22C38/32 ,  C22C38/42 ,  C22C38/44 ,  C22C38/46 ,  C22C38/48 ,  C22C38/50 ,  C22C38/52 ,  C22C38/54 ,  C22C38/56 ,  C22C38/60 ,  C23C2/285 ,  C23C2/40 ,  C21D2211/001 ,  C21D2211/002 ,  C21D2211/005 ,  C21D2211/008

Abstract: The hot dip galvannealed steel sheet of the present disclosure has a base steel sheet and a plating layer. The base steel sheet has a predetermined chemical composition by mass %. An existence ratio ER of internal oxides identified under predetermined conditions by observation of the cross-section of the base steel sheet is 40% or less and an interval I of internal oxides is 300 μm or more. The hot dip galvannealed steel sheet of the present disclosure is excellent in appearance etc.