公开(公告)号：US20250003037A1

公开(公告)日：2025-01-02

申请号：US18811384

申请日：2024-08-21

Applicant: ArcelorMittal

Inventor： Sebastian COBO ,  Emmanuel LUCAS ,  Matthieu SALIB ,  Guillaume STECHMANN

IPC: C22C38/04 ,  C21D8/02 ,  C22C38/00 ,  C22C38/02 ,  C22C38/06 ,  C22C38/14

Abstract: A steel sheet has a chemical composition including in wt % C: 0.2-0.4%, Mn: 0.8-2.0%, Si: 0.1-0.5%, Al: 0.01-0.1%, Ti: 0.01-0.1%, B: 0.0005-0.005%, P≤0.040%, Ca≤0.01%, S≤0.006%, N≤0.01%. The steel sheet includes from the bulk to the surface of the coated steel sheet a bulk and a skin layer occupying the outermost 10% of the thickness on either side of the bulk. The bulk includes an inclusion population in which the sum of clustering indexes of MnS and TiN/Ti(C,N) inclusions is less than or equal to 300 μm/mm2. This allows to manufacture hot pressed parts having a tensile strength equal to or greater than 1300 MPa and a bending anisotropy equal to or lower than 7°.

公开(公告)号：US20250137105A1

公开(公告)日：2025-05-01

申请号：US18988516

申请日：2024-12-19

Applicant: ArcelorMittal

Inventor： Sebastian COBO ,  Emmanuel LUCAS ,  Matthieu SALIB ,  Guillaume STECHMANN

IPC: C22C38/04 ,  C21D8/02 ,  C22C38/00 ,  C22C38/02 ,  C22C38/06 ,  C22C38/14

Abstract: A steel sheet hasa chemical composition including in wt % C: 0.2-0.4%, Mn: 0.8-2.0%, Si: 0.1-0.5%, Al: 0.01-0.1%, Ti: 0.01-0.1%, B: 0.0005-0.005%, P≤0.040%, Ca≤0.01%, S≤0.006%, N≤0.01%. The steel sheet includes from the bulk to the surface of the coated steel sheet a bulk and a skin layer occupying the outermost 10% of the thickness on either side of the bulk. The bulk includes an inclusion population in which the sum of clustering indexes of MnS and TiN/Ti(C,N) inclusions is less than or equal to 300 μm/mm2. This allows to manufacture hot pressed parts having a tensile strength equal to or greater than 1300 MPa and a bending anisotropy equal to or lower than 7°.

公开(公告)号：US20250137083A1

公开(公告)日：2025-05-01

申请号：US19011522

申请日：2025-01-06

Applicant: ArcelorMittal

Inventor： Alice DUMONT ,  Guillaume STECHMANN ,  Emmanuel LUCAS ,  Matthieu SALIB

IPC: C21D9/00 ,  C21D1/18 ,  C21D6/00 ,  C21D7/13 ,  C21D8/00 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/28 ,  C22C38/32

Abstract: A steel sheet having a chemical composition including in wt % C: 0.2-0.4%, Mn: 0.8-2.0%, Si: 0.1-0.5%, Al: 0.01-0.1%, Ti: 0.01-0.1%, B: 0.0005-0.005%, P≤0.040%, Ca≤0.01%, S≤0.006%, N≤0.01%. The steel sheet includes from the bulk to the surface of the coated steel sheet a bulk and a skin layer occupying the outermost 10% of the thickness on either side of the bulk. The bulk is topped by a skin layer occupying the outermost 10% of the thickness on either side of the bulk, the density of TiN/Ti(C,N) inclusions in the skin being smaller than 240 particles/mm2 and the clustering index of MnS inclusions in the skin being lower than 110 μm/mm2. This allows to manufacture hot pressed parts having a tensile strength equal to or greater than 1300 MPa and a bending angle normalized to 1.5 mm and measured in the transverse direction strictly greater than 48°.

公开(公告)号：US20240102138A1

公开(公告)日：2024-03-28

申请号：US18266682

申请日：2021-12-03

Applicant: ARCELORMITTAL

Inventor： Clément PHILIPPOT ,  Sandra LEGUILLARD ,  David DUSSAUSSOIS ,  Matthieu SALIB

IPC: C22C38/38 ,  B21C47/02 ,  C21D8/02 ,  C21D8/04 ,  C22C38/02 ,  C22C38/06 ,  C22C38/28 ,  C22C38/32 ,  C23C2/02 ,  C23C2/12 ,  C23C2/28 ,  C23C2/40

CPC classification number: C22C38/38 ,  B21C47/02 ,  C21D8/0205 ,  C21D8/0226 ,  C21D8/0273 ,  C21D8/0278 ,  C21D8/0436 ,  C22C38/02 ,  C22C38/06 ,  C22C38/28 ,  C22C38/32 ,  C23C2/0224 ,  C23C2/12 ,  C23C2/29 ,  C23C2/40 ,  C21D2211/002 ,  C21D2211/005 ,  C21D2211/008

Abstract: A coated steel sheet and press hardened steel part having a composition including, by weight percent: C 0.26-0.40%, Mn 0.5-1.8%, Si 0.1-1.25%, Al 0.01-0.1%, Cr 0.1-1.0%, Ti 0.01-0.1%, B 0.001-0.004%, P 0.020%, S 0.010%, N 0.010% the remainder of the composition being iron and unavoidable impurities resulting from the smelting. The press hardened steel part includes a bulk having a microstructure including, in surface fraction, more than 95% of martensite and less than 5% of bainite, a coating layer at the surface of the steel part, a ferritic interdiffusion layer between the coating layer and the bulk, and a ratio between the ferritic grain width in the interdiffusion layer GWint over prior austenite grain size in the bulk PAGSbulk, satisfying following equation (GWint/PAGSbulk)−1≥30%.