公开(公告)号：US12098440B2

公开(公告)日：2024-09-24

申请号：US18033729

申请日：2021-08-31

Applicant: NIPPON STEEL CORPORATION

Inventor： Takafumi Yokoyama ,  Yusuke Tsunemi ,  Tatsuya Obuchi ,  Akinobu Minami ,  Takuya Kuwayama

IPC: C22C38/58 ,  B32B15/01 ,  B32B15/04 ,  B32B15/18 ,  C21D1/18 ,  C21D6/00 ,  C21D8/02 ,  C21D9/46 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/08 ,  C22C38/10 ,  C22C38/12 ,  C22C38/14 ,  C22C38/16 ,  C22C38/18 ,  C22C38/20 ,  C22C38/22 ,  C22C38/24 ,  C22C38/26 ,  C22C38/28 ,  C22C38/32 ,  C22C38/38 ,  C22C38/42 ,  C22C38/44 ,  C22C38/46 ,  C22C38/50 ,  C22C38/52 ,  C22C38/60 ,  C23C2/02 ,  C23C2/28 ,  C23C30/00 ,  C23C2/06 ,  C23C2/40 ,  C23G1/08

CPC classification number: C21D9/46 ,  B32B15/013 ,  B32B15/04 ,  B32B15/043 ,  B32B15/18 ,  C21D1/18 ,  C21D6/001 ,  C21D6/002 ,  C21D6/004 ,  C21D6/005 ,  C21D6/007 ,  C21D6/008 ,  C21D8/02 ,  C21D8/0205 ,  C21D8/0226 ,  C21D8/0236 ,  C21D8/0263 ,  C21D8/0273 ,  C21D8/0278 ,  C22C38/00 ,  C22C38/001 ,  C22C38/002 ,  C22C38/005 ,  C22C38/008 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/08 ,  C22C38/10 ,  C22C38/12 ,  C22C38/14 ,  C22C38/16 ,  C22C38/18 ,  C22C38/20 ,  C22C38/22 ,  C22C38/24 ,  C22C38/26 ,  C22C38/28 ,  C22C38/32 ,  C22C38/38 ,  C22C38/42 ,  C22C38/44 ,  C22C38/46 ,  C22C38/50 ,  C22C38/52 ,  C22C38/58 ,  C22C38/60 ,  C23C2/02 ,  C23C2/0224 ,  C23C2/024 ,  C23C2/285 ,  C23C30/00 ,  C23C30/005 ,  C21D2211/001 ,  C21D2211/002 ,  C21D2211/003 ,  C21D2211/005 ,  C21D2211/008 ,  C21D2211/009 ,  C23C2/06 ,  C23C2/28 ,  C23C2/40 ,  C23G1/08 ,  Y10T428/12757 ,  Y10T428/12799 ,  Y10T428/12965 ,  Y10T428/12972 ,  Y10T428/12993

Abstract: Provided are a steel sheet having a predetermined chemical composition, and a steel microstructure comprising, by vol %, ferrite: 1 to 50%, ratio of nonrecrystallized ferrite in the ferrite: 0 to 50%, tempered martensite: 1% or more, retained austenite: 5% or more, fresh martensite: 0 to 10%, total of pearlite and cementite: 0 to 5%, and balance: bainite, and, when analyzing the surface by an EPMA, an area ratio of regions with an AlS/SiS ratio of 0.2 or less is 50% or less, and a tensile strength is 980 MPa or more, and a method for producing the same.

公开(公告)号：US20240309481A1

公开(公告)日：2024-09-19

申请号：US18262810

申请日：2022-02-09

Applicant: BAOSHAN IRON & STEEL CO., LTD.

Inventor： Shuangcheng WANG ,  Quanshe SUN

IPC: C21D9/46 ,  C21D1/18 ,  C21D6/00 ,  C21D8/02 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/20 ,  C22C38/32

CPC classification number: C21D9/46 ,  C21D1/18 ,  C21D6/002 ,  C21D6/005 ,  C21D6/008 ,  C21D8/0205 ,  C21D8/0226 ,  C21D8/0263 ,  C22C38/001 ,  C22C38/002 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/20 ,  C22C38/32 ,  C21D2211/005 ,  C21D2211/009

Abstract: Disclosed is a low-cost hot-rolled steel plate for high temperature enameling. In addition to Fe and inevitable impurities, the plate further comprises a chemical composition in mass percentage as follows: C: 0.03-0.12%, Si: 0.1-0.5%, Mn: 0.3-1.5%, P: 0.03-0.10%, Al: 0.02-0.10%, Cr: 0.01-0.20%, Cu: 0.01-0.30%, N: 0.007-0.020%, and B: 0.0006-0.003%. The low-cost hot-rolled steel plate for high temperature enameling does not contain Ti, Nb, and V. The chemical composition further satisfies: P×(N−14×B/11)×103>0.3, and in the calculation, P, N, and B are respectively substituted with the numerical value before the percent sign in the mass percentage of the corresponding chemical element. Further disclosed is a manufacturing method for a low-cost hot-rolled steel plate for high temperature enameling, which comprises the following steps: (1) smelting and casting; (2) heating; (3) hot rolling: controlling the rough rolling temperature at above 850° C., the finish rolling start temperature at 900-1050° C., and the finish rolling end temperature at 840-900° C.; (4) laminar cooling: controlling the cooling rate at 10-35° C./s; and (5) coiling.

公开(公告)号：US12084737B2

公开(公告)日：2024-09-10

申请号：US18471144

申请日：2023-09-20

Applicant: Yanshan University

Inventor： Zhinan Yang ,  Fucheng Zhang ,  Jianjun Wang ,  Hongguang Li ,  Zhuanqin Liang ,  Qingchao Wang ,  Changbo Liu ,  Dongyun Sun ,  Xinliang Gao ,  Chen Chen

IPC: C21D9/04 ,  C21D1/84 ,  C21D6/00 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/44 ,  C22C38/46 ,  C22C38/48 ,  C22C38/50 ,  C22C38/54

CPC classification number: C21D9/04 ,  C21D1/84 ,  C21D6/004 ,  C21D6/005 ,  C21D6/008 ,  C22C38/001 ,  C22C38/002 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/44 ,  C22C38/46 ,  C22C38/48 ,  C22C38/50 ,  C22C38/54 ,  C21D2211/002 ,  C21D2211/005 ,  C21D2211/009

Abstract: A gradient-structured ultra-fine bainitic low-alloy rail steel and a preparation method thereof are provided in the present application, belonging to the technical field of steel metallurgy. The rail steel to be treated is subjected to three thermal processing treatments so that the gradient-structured ultra-fine bainitic rail steel has a gradient structure consisting of a ferrite-pearlite dual phase microstructure and an ultra-fine bainite microstructure. The gradient structure of the present application enables the matrix of the rail to be a ferrite-pearlite composite phase structure, and only the surface layer of the service surface to be ultrafine bainite.

公开(公告)号：US20240287663A1

公开(公告)日：2024-08-29

申请号：US18568329

申请日：2022-07-12

Applicant: NIPPON STEEL CORPORATION

Inventor： Kyohei ISHIKAWA

IPC: C22C38/54 ,  C21D1/18 ,  C21D6/00 ,  C21D8/02 ,  C21D9/46 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/12 ,  C22C38/14 ,  C22C38/16 ,  C22C38/22 ,  C22C38/24 ,  C22C38/26 ,  C22C38/28 ,  C22C38/32 ,  C22C38/34 ,  C22C38/38 ,  C22C38/42 ,  C22C38/44 ,  C22C38/48

CPC classification number: C22C38/54 ,  C21D1/18 ,  C21D6/002 ,  C21D6/004 ,  C21D6/005 ,  C21D6/008 ,  C21D8/0205 ,  C21D8/0226 ,  C21D8/0236 ,  C21D8/0257 ,  C21D8/0263 ,  C21D8/0278 ,  C21D9/46 ,  C22C38/001 ,  C22C38/002 ,  C22C38/005 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/12 ,  C22C38/14 ,  C22C38/16 ,  C22C38/22 ,  C22C38/24 ,  C22C38/26 ,  C22C38/28 ,  C22C38/32 ,  C22C38/34 ,  C22C38/38 ,  C22C38/42 ,  C22C38/44 ,  C22C38/48 ,  C21D2211/001 ,  C21D2211/002 ,  C21D2211/005 ,  C21D2211/008 ,  C21D2211/009

Abstract: Provided is a high strength steel sheet comprising a sheet thickness center part and a surface layer soft part formed at one side or both sides of the sheet thickness center part, wherein the sheet thickness center part has a predetermined chemical composition and has a microstructure comprising tempered martensite: 85% or more, the surface layer soft part has a thickness of more than 10 μm to 5.0% or less of the sheet thickness, a microstructure comprising ferrite: 80% or more, and an internal oxide layer having a thickness of 3 μm or more from the surface, an average Vickers hardness (Hc) of the sheet thickness center part and an average Vickers hardness (Hs) of the surface layer soft part satisfy Hs/Hc≤0.50, and a void area ratio in a region from the surface down to a 10 μm depth position is 3.0% or less.

公开(公告)号：US20240254582A1

公开(公告)日：2024-08-01

申请号：US18019183

申请日：2021-08-11

Applicant: POSCO Co., Ltd

Inventor： Wan-Keun Kim ,  Duk-Gyu Kim

IPC: C21D8/02 ,  C21D9/46 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/08 ,  C22C38/12 ,  C22C38/14

CPC classification number: C21D8/0226 ,  C21D8/0263 ,  C21D9/46 ,  C22C38/001 ,  C22C38/002 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/08 ,  C22C38/12 ,  C22C38/14 ,  C21D2211/002 ,  C21D2211/005 ,  C21D2211/009

Abstract: The present invention relates to a steel sheet suitable as a material for transporting oil and gas, more particularly, to a hot-rolled steel sheet having excellent impact toughness in a welded zone after electric resistance welding (ERW), and to a hot-rolled steel sheet having excellent impact toughness at a cryogenic temperature of −20° C. or lower, that makes the sheet applied in a cold area, and a method for manufacturing same.

公开(公告)号：US12049687B2

公开(公告)日：2024-07-30

申请号：US17773401

申请日：2020-10-26

Applicant: POSCO

Inventor： Sung-Il Kim ,  Hyun-Taek Na

IPC: C22C38/28 ,  C21D8/02 ,  C21D9/46 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/26 ,  C23C2/06 ,  C23C2/12 ,  C23C2/40 ,  C23G1/00

CPC classification number: C22C38/28 ,  C21D8/0226 ,  C21D9/46 ,  C22C38/001 ,  C22C38/002 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/26 ,  C23C2/06 ,  C23C2/12 ,  C23C2/40 ,  C23G1/00 ,  C21D2211/001 ,  C21D2211/002 ,  C21D2211/005 ,  C21D2211/008 ,  C21D2211/009 ,  Y10T428/12799

Abstract: Thick high-strength steel having a high yield ratio and excellent durability, and a method for manufacturing same are provided. The thick high-strength steel having a high yield ratio and excellent durability of the present invention comprises, in percentage by weight, C: 0.05 to 0.15%, Si: 0.01 to 1.0%, Mn: 1.0 to 2.3%, Al: 0.01 to 0.1%, Cr: 0.005 to 1.0%, P: 0.001 to 0.05%, S: 0.001 to 0.01%, N: 0.001 to 0.01%, Nb: 0.005 to 0.07%, Ti 0.005 to 0.11%, Fe and unavoidable impurities.

公开(公告)号：US20240240298A1

公开(公告)日：2024-07-18

申请号：US18559094

申请日：2022-05-16

Applicant: Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.)

Inventor： Sae HAMAMOTO ,  Haruka ARAKI ,  Michitaka TSUNEZAWA

IPC: C23C2/06 ,  C21D8/02 ,  C21D9/46 ,  C22C38/00 ,  C22C38/02 ,  C22C38/06 ,  C22C38/42 ,  C22C38/44 ,  C22C38/46 ,  C22C38/48 ,  C22C38/50 ,  C22C38/54 ,  C22C38/58 ,  C22C38/60 ,  C23C2/40

CPC classification number: C23C2/06 ,  C21D8/0226 ,  C21D8/0236 ,  C21D8/0247 ,  C21D9/46 ,  C22C38/001 ,  C22C38/002 ,  C22C38/005 ,  C22C38/02 ,  C22C38/06 ,  C22C38/42 ,  C22C38/44 ,  C22C38/46 ,  C22C38/48 ,  C22C38/50 ,  C22C38/54 ,  C22C38/58 ,  C22C38/60 ,  C23C2/40 ,  C21D2211/001 ,  C21D2211/002 ,  C21D2211/005 ,  C21D2211/008 ,  C21D2211/009

Abstract: A high-strength hot-dip galvannealed steel sheet may include a plating layer on a surface of a base steel sheet. The base steel sheet may satisfy a predetermined chemical composition, in a metallographic structure of the base steel sheet, wherein a volume ratio of martensite (including tempered martensite and self-tempered martensite) is 82 vol % or more, a volume ratio of ferrite, pearlite and bainite is 13 vol % or less in total, and volume ratio of retained austenite is 5 vol % or less, in an image obtained by observing the metallographic structure of the base steel sheet with a scanning electron microscope, the number of laths at a total length of 300 μm, the number being measured by an intercept method is 200 or more, a yield strength is 970 MPa or more, and a tensile strength is 1,470 MPa or more.

公开(公告)号：US20240218478A1

公开(公告)日：2024-07-04

申请号：US18471144

申请日：2023-09-20

Applicant: Yanshan University

Inventor： Zhinan YANG ,  Fucheng ZHANG ,  Jianjun WANG ,  Hongguang LI ,  Zhuanqin LIANG ,  Qingchao WANG ,  Changbo LIU ,  Dongyun SUN ,  Xinliang GAO ,  Chen CHEN

IPC: C21D9/04 ,  C21D1/84 ,  C21D6/00 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/44 ,  C22C38/46 ,  C22C38/48 ,  C22C38/50 ,  C22C38/54

CPC classification number: C21D9/04 ,  C21D1/84 ,  C21D6/004 ,  C21D6/005 ,  C21D6/008 ,  C22C38/001 ,  C22C38/002 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/44 ,  C22C38/46 ,  C22C38/48 ,  C22C38/50 ,  C22C38/54 ,  C21D2211/002 ,  C21D2211/005 ,  C21D2211/009

Abstract: A gradient-structured ultra-fine bainitic low-alloy rail steel and a preparation method thereof are provided in the present application, belonging to the technical field of steel metallurgy. The rail steel to be treated is subjected to three thermal processing treatments so that the gradient-structured ultra-fine bainitic rail steel has a gradient structure consisting of a ferrite-pearlite dual phase microstructure and an ultra-fine bainite microstructure. The gradient structure of the present application enables the matrix of the rail to be a ferrite-pearlite composite phase structure, and only the surface layer of the service surface to be ultrafine bainite.

公开(公告)号：US20240191319A1

公开(公告)日：2024-06-13

申请号：US18553034

申请日：2022-04-01

Applicant: Salzgitter Flachstahl GmbH

Inventor： Jan Roik ,  Manuel Maikranz-Valentin ,  Konstantin D. Molodov

IPC: C21D9/52 ,  C21D1/18 ,  C21D6/00 ,  C22C38/00 ,  C22C38/02 ,  C22C38/06 ,  C22C38/20 ,  C22C38/22 ,  C22C38/24 ,  C22C38/26 ,  C22C38/28 ,  C22C38/32 ,  C22C38/38

CPC classification number: C21D9/52 ,  C21D1/18 ,  C21D6/002 ,  C21D6/005 ,  C21D6/008 ,  C22C38/001 ,  C22C38/002 ,  C22C38/02 ,  C22C38/06 ,  C22C38/20 ,  C22C38/22 ,  C22C38/24 ,  C22C38/26 ,  C22C38/28 ,  C22C38/32 ,  C22C38/38 ,  C21D2211/001 ,  C21D2211/002 ,  C21D2211/005 ,  C21D2211/008 ,  C21D2211/009

Abstract: A steel strip made of a high-strength multiphase steel with a tensile strength of at least 780 MPa in the longitudinal direction and consists of the following elements in % by weight: 0.08≤C≤0.23, 1.5≤Mn≤3.5, 0.25≤Si+Al≤2, 0.0020≤N≤0.0160, P

公开(公告)号：US20240183017A1

公开(公告)日：2024-06-06

申请号：US18285505

申请日：2022-05-10

Applicant: NIPPON STEEL CORPORATION

Inventor： Yuri TODA ,  Daisuke MAEDA ,  Tamaki SUZUKI ,  Ko SATAKE ,  Yuma ASADA

IPC: C22C38/60 ,  B21D22/02 ,  C21D8/02 ,  C21D9/46 ,  C22C38/00 ,  C22C38/20 ,  C22C38/22 ,  C22C38/24 ,  C22C38/26 ,  C22C38/28 ,  C22C38/30 ,  C22C38/32 ,  C22C38/44 ,  C22C38/48 ,  C22C38/50 ,  C22C38/54

CPC classification number: C22C38/60 ,  B21D22/022 ,  C21D8/0205 ,  C21D8/0226 ,  C21D8/0236 ,  C21D8/0263 ,  C21D9/46 ,  C22C38/001 ,  C22C38/002 ,  C22C38/005 ,  C22C38/008 ,  C22C38/20 ,  C22C38/22 ,  C22C38/24 ,  C22C38/26 ,  C22C38/28 ,  C22C38/30 ,  C22C38/32 ,  C22C38/44 ,  C22C38/48 ,  C22C38/50 ,  C22C38/54 ,  C21D2211/001 ,  C21D2211/005 ,  C21D2211/009

Abstract: This hot-stamping formed body has a predetermined chemical composition and has a microstructure in which an average grain size of prior austenite grains is 5 to 25 μm, and a standard deviation of grain sizes of the prior austenite grains is 0.1 to 2.0 μm. In addition, this steel sheet for hot stamping has a predetermined chemical composition and has a microstructure in which an average value of the pole densities of ferrite in the orientation group consisting of {100} to {223} is 10.0 or less, in entire ferrite, a number proportion of ferrite containing a carbide having an equivalent circle diameter of 0.2 μm or more in grains is 20% or more, and the steel sheet for hot stamping has a microstructure in which an area ratio of pearlite is 10% to 90% and an ratio of ferrite is 10% to 90%.