公开(公告)号：US20240033804A1

公开(公告)日：2024-02-01

申请号：US18484254

申请日：2023-10-10

Applicant: NIPPON STEEL CORPORATION

Inventor： Takashi YASUTOMI ,  Shigeru YONEMURA ,  Tohru YOSHIDA

IPC: B21D28/34 ,  B23D15/04 ,  B23D35/00 ,  B26D1/01 ,  B26D7/06 ,  B26D7/26

CPC classification number: B21D28/34 ,  B23D15/04 ,  B23D35/005 ,  B26D1/01 ,  B26D7/06 ,  B26D7/2628 ,  B26D2001/0066

Abstract: A shearing method of a plate-shaped workpiece for applying a shear force in a thickness direction of the plate-shaped workpiece includes: a step for starting applying the shear force on the workpiece with a clearance between action points in a surface direction orthogonal to the thickness direction of the workpiece; a step for applying the shear force after the start of applying the shear force until a fractured surface is created in the workpiece; and a step for increasing the clearance depending on a deformation of the workpiece in the thickness direction after starting applying the shear force until the fractured surface is created in the workpiece.

公开(公告)号：US20230140766A1

公开(公告)日：2023-05-04

申请号：US17908553

申请日：2021-04-21

Applicant: NIPPON STEEL CORPORATION

Inventor： Eisaku SAKURADA ,  Takashi YASUTOMI ,  Genki ABUKAWA

IPC: C21D8/02 ,  C21D9/46 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/22 ,  C22C38/24 ,  C22C38/26 ,  C22C38/28 ,  C22C38/32 ,  C23C2/40 ,  B21C47/02

Abstract: This hot-rolled steel sheet has a predetermined chemical composition and predetermined metallographic structure, a ratio between a maximum depth of a region where, on one surface, a rotation angle between a normal line of the one surface and a (011) pole near the normal line of the one surface is 5° or less and a maximum depth of a region where, on the other surface, a rotation angle between a normal line of the other surface and a (011) pole near the normal line of the other surface is 5° or less is 1.00 to 1.20, and a tensile strength is 1150 MPa or more.

公开(公告)号：US20250144693A1

公开(公告)日：2025-05-08

申请号：US18835697

申请日：2022-02-03

Applicant: NIPPON STEEL CORPORATION

Inventor： Yoshiaki HONDA ,  Yuji SAKIYAMA ,  Takashi YASUTOMI ,  Masahiro NAKATA

IPC: B21D28/00

Abstract: A steel material reduced in tensile residual stress at a sheared edge, in particular a fractured surface, is disclosed. The steel material of the present disclosure has a sheared edge, the sheared edge has a rollover, a fractured surface, and a burr, the fractured surface includes a first part and a second part, the first part is formed by a first crack propagating from the rollover side to the burr side, the second part is formed by a second crack propagating from the burr side to the rollover side, and an area ratio of the first part in the fractured surface is greater than an area ratio of the second part in the fractured surface.

公开(公告)号：US20240068066A1

公开(公告)日：2024-02-29

申请号：US18280105

申请日：2022-02-22

Applicant: NIPPON STEEL CORPORATION

Inventor： Yasuaki TANAKA ,  Shohei YABU ,  Hiroshi SHUTO ,  Koutarou HAYASHI ,  Takashi YASUTOMI ,  Eisaku SAKURADA

IPC: C21D9/46 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/14 ,  C22C38/60

CPC classification number: C21D9/46 ,  C22C38/001 ,  C22C38/002 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/14 ,  C22C38/60

Abstract: There is provided a steel sheet having a chemical composition comprising, in mass %, C: 0.05 to 0.25%, Si: 0.2 to 2.0%, Mn: 1.2 to 3.0%, P: 0.030% or less, S: 0.050% or less, Al: 0.01 to 0.55%, N: 0.0100% or less, and Ti: 0.010 to 0.250%, with the balance: Fe and impurities, wherein a random intensity ratio of a texture in a near-surface portion of the steel sheet is 8.0 or less, and a minimum angle formed between a maximum strength orientation in a {110} pole figure of the texture and a normal direction of a rolled surface of the steel sheet is 10° or less.

公开(公告)号：US20230250521A1

公开(公告)日：2023-08-10

申请号：US18008639

申请日：2021-08-06

Applicant: NIPPON STEEL CORPORATION

Inventor： Yuji SAKIYAMA ,  Takashi YASUTOMI ,  Katsuya NAKANO ,  Yoshiaki HONDA ,  Masahiro NAKATA

IPC: C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/60 ,  C22C38/00 ,  C22C38/22 ,  C22C38/32 ,  C22C38/46 ,  C22C38/48 ,  C22C38/42 ,  B32B15/01

CPC classification number: C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/60 ,  C22C38/001 ,  C22C38/22 ,  C22C38/32 ,  C22C38/46 ,  C22C38/48 ,  C22C38/42 ,  B32B15/011 ,  B32B2311/30 ,  B32B2307/536 ,  B32B2307/54

Abstract: Provided is a steel sheet comprising a sheet thickness center part and a first surface layer part and a second surface layer part respectively arranged at two sides of the sheet thickness center part, wherein the first surface layer part and second surface layer part respectively independently have thicknesses of more than 10 μm to 30% or less of the sheet thickness, the first surface layer part and second surface layer part have average Vickers hardnesses different from the average Vickers hardness of a sheet thickness ½ position, and a first hardness cumulative value at a region from a surface of the first surface layer part side to 30% of the sheet thickness is 1.05 times or more of a second hardness cumulative value at a region from a surface of the second surface layer part side to 30% of the sheet thickness.

公开(公告)号：US20230097055A1

公开(公告)日：2023-03-30

申请号：US17794672

申请日：2021-04-21

Applicant: NIPPON STEEL CORPORATION

Inventor： Eisaku SAKURADA ,  Takashi YASUTOMI ,  Genki ABUKAWA

IPC: C21D9/46 ,  C22C38/38 ,  C22C38/34 ,  C22C38/32 ,  C22C38/28 ,  C22C38/26 ,  C22C38/24 ,  C22C38/22 ,  C22C38/06 ,  C21D8/02

Abstract: Adopted are a hot-rolled steel sheet having a predetermined chemical composition, in which a region, where a rotation angle between a normal line of a surface and a (011) pole near the normal line becomes 5° or less, is 0.150 or less from the surface in terms of a sheet thickness direction position standardized by a sheet thickness, and a region, where the rotation angle becomes 20° or more, is 0.250 or more from the surface in terms of the sheet thickness direction position standardized by the sheet thickness and a manufacturing method thereof.

公开(公告)号：US20220250177A1

公开(公告)日：2022-08-11

申请号：US17438056

申请日：2020-01-09

Applicant: NIPPON STEEL CORPORATION

Inventor： Takashi YASUTOMI ,  Akinobu KOBAYASHI

IPC: B23D15/08 ,  B21D28/14 ,  B21D28/26 ,  B21D28/34 ,  B23D35/00

Abstract: There is provided a cutting method for cutting a workpiece using a cutting tool comprising a die and a punch, including: arranging the workpiece between the die and the punch, and in a state in which a wedge-shaped first cutting part of the die and a wedge-shaped second cutting part of the punch are opposed, pushing the punch relatively to the die side to cut the workpiece; wherein: a front end angle θ1 of the first cutting part and a front end angle θ2 of the second cutting part are each 100 or more and 1200 or less, and a front end radius R1 of the first cutting part and a front end radius R2 of the second cutting part are each 0.5% or more and 35.0% or less of a sheet thickness.

公开(公告)号：US20230416859A1

公开(公告)日：2023-12-28

申请号：US18031104

申请日：2021-11-18

Applicant: NIPPON STEEL CORPORATION

Inventor： Hideto HIROSHIMA ,  Takashi YASUTOMI ,  Eisaku SAKURADA

IPC: C21D9/46 ,  C22C38/38 ,  C22C38/32 ,  C22C38/28 ,  C22C38/26 ,  C22C38/24 ,  C22C38/22 ,  C22C38/14 ,  C22C38/12 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/00 ,  C21D8/02 ,  C21D6/00 ,  C21D1/18

CPC classification number: C21D9/46 ,  C21D2211/001 ,  C22C38/32 ,  C22C38/28 ,  C22C38/26 ,  C22C38/24 ,  C22C38/22 ,  C22C38/14 ,  C22C38/12 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/002 ,  C22C38/001 ,  C21D8/0205 ,  C21D8/0226 ,  C21D8/0263 ,  C21D6/002 ,  C21D6/005 ,  C21D6/008 ,  C21D1/18 ,  C21D2211/002 ,  C21D2211/005 ,  C21D2211/008 ,  C21D2211/009 ,  C22C38/38

Abstract: This steel sheet has a predetermined chemical composition, has a microstructure in which a number density of alloy carbides present at grain boundaries and having a major axis of 10 to 100 nm is 1.0×108 to 1.0×1011/cm2 and a number density of alloy carbides present in grains and having a major axis of 10 nm or less is 1.0×1016 to 1.0×1019/cm3, and has a tensile strength of 1,030 MPa or more.

公开(公告)号：US20230407430A1

公开(公告)日：2023-12-21

申请号：US18036996

申请日：2021-11-19

Applicant: NIPPON STEEL CORPORATION

Inventor： Takashi YASUTOMI ,  Eisaku SAKURADA

IPC: C21D9/46 ,  C22C38/38 ,  C22C38/32 ,  C22C38/28 ,  C22C38/26 ,  C22C38/24 ,  C22C38/22 ,  C22C38/14 ,  C22C38/12 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/00 ,  C21D8/02 ,  C21D6/00 ,  C21D1/18

CPC classification number: C21D9/46 ,  C22C38/38 ,  C22C38/32 ,  C22C38/28 ,  C22C38/26 ,  C22C38/24 ,  C22C38/22 ,  C22C38/14 ,  C22C38/12 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/002 ,  C22C38/001 ,  C21D8/0205 ,  C21D8/0226 ,  C21D8/0263 ,  C21D6/002 ,  C21D6/005 ,  C21D6/008 ,  C21D1/18 ,  C21D8/021 ,  C21D8/0278 ,  C21D2211/002 ,  C21D2211/008

Abstract: This steel sheet has predetermined chemical composition and microstructure, in a crystal orientation distribution function of a texture at a sheet thickness ¼ position, when A/B that is a ratio of a maximum value A of pole densities at Φ=20° to 60° and φ1=30° to 90° in a cross section of φ2=45° to a maximum value B of pole densities at Φ=120° to 60° and φ1=30° to 90° in the cross section of φ2=45° is 1.50 or less, a total of the maximum value A and the maximum value B is 6.00 or less, and a tensile strength is 1030 MPa or more.

公开(公告)号：US20230257844A1

公开(公告)日：2023-08-17

申请号：US18012882

申请日：2021-08-06

Applicant: NIPPON STEEL CORPORATION

Inventor： Katsuya NAKANO ,  Yuji SAKIYAMA ,  Takashi YASUTOMI ,  Yoshiaki HONDA ,  Masahiro NAKATA

IPC: C21D9/46 ,  C21D8/02 ,  C21D6/00 ,  C22C38/60 ,  C22C38/14 ,  C22C38/12 ,  C22C38/16 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/00 ,  C22C38/10 ,  C22C38/08 ,  C22C38/18 ,  C21D3/04

CPC classification number: C21D9/46 ,  C21D8/0205 ,  C21D8/0226 ,  C21D8/0236 ,  C21D6/005 ,  C21D6/008 ,  C22C38/60 ,  C22C38/14 ,  C22C38/12 ,  C22C38/16 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/008 ,  C22C38/002 ,  C22C38/10 ,  C22C38/08 ,  C22C38/18 ,  C22C38/001 ,  C22C38/005 ,  C21D3/04 ,  C21D8/0257

Abstract: Provided is a steel sheet comprising a sheet thickness center part and a first surface layer softened part and a second surface layer softened part respectively arranged at two sides of the sheet thickness center part, wherein the first surface layer softened part and second surface layer softened part have 10 μm or more average thicknesses and have average Vickers hardnesses of 0.90 time or less of the average Vickers hardness of a sheet thickness ½ position, and the first surface layer softened part has an average Vickers hardness of 1.05 times or more the average Vickers hardness of the second surface layer softened part.