公开(公告)号：US20220241838A1

公开(公告)日：2022-08-04

申请号：US17626321

申请日：2020-07-10

Applicant: NIPPON STEEL CORPORATION

Inventor： Jun NITTA ,  Takashi YASUTOMI ,  Ryo TABATA

IPC: B21D28/34 ,  B21D28/14 ,  B23D15/08

Abstract: The present invention has as its technical problem to provide a punching method able to stably secure a stretch-flangeability equal to or greater than the case of using a punch having a flat blade at its bottom surface. The punching method of the present invention is a method of punching a metal sheet using a punching and shearing device provided with a punch having an upper blade having a horizontal part with respect to the cutting line in part and having parts other than the horizontal part comprised of inclined parts and a die having a lower blade wherein the upper blade used for the punching process has a shape where the inclined parts first contact the metal sheet at the time of a punching process.

公开(公告)号：US20200030868A1

公开(公告)日：2020-01-30

申请号：US16498364

申请日：2018-03-20

Applicant: NIPPON STEEL CORPORATION

Inventor： Takashi YASUTOMI ,  Shigeru YONEMURA ,  Tohru YOSHIDA

IPC: B21D28/34

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：US20230082468A1

公开(公告)日：2023-03-16

申请号：US17798246

申请日：2020-12-16

Applicant: NIPPON STEEL CORPORATION

Inventor： Yoshinari ISHIDA ,  Akinobu KOBAYASHI ,  Takashi YASUTOMI

IPC: F16B5/08 ,  B23K9/02

Abstract: According to one aspect of the present invention, there is provided a T-joint including a first steel sheet, a second steel sheet, and a fillet welded part, in which the sheet thickness of the second steel sheet is 6.0 mm or less, the second steel sheet is stood on a first surface of the first steel sheet, the fillet welded part joins the first surface of the first steel sheet and a first surface of the second steel sheet to each other, at least one of the first surface of the first steel sheet or the first surface of the second steel sheet includes a zinc-based plating, an abutting end portion of the second steel sheet on a second surface side of the second steel sheet has an inclined surface, and in a cross section taken along a sheet thickness direction of the first steel sheet and a sheet thickness direction of the second steel sheet, the inclined surface forms an acute angle with respect to the first surface of the first steel sheet.

公开(公告)号：US20220195548A1

公开(公告)日：2022-06-23

申请号：US17599926

申请日：2020-04-10

Applicant: NIPPON STEEL CORPORATION

Inventor： Yasuhiro ITO ,  Takashi YASUTOMI ,  Soma SONOBE

IPC: C21D8/02 ,  B21D53/88 ,  B21D35/00 ,  C21D9/46

Abstract: A blank (100) includes a main portion (110) that is made of steel having a tensile strength of 1450 MPa or more and a softened portion (120), the ratio of Vickers hardness of the softened portion (120) to the Vickers hardness of the main portion (110) is 0.7 or more and 0.95 or less, and the softened portion (120) is disposed at a position different from a position of the main portion (110) in an in-plane direction. A structural member (200) includes a first member (210), a second member (220), and a weld (W) at which the first member (210) and the second member (220) are welded to each other.

公开(公告)号：US20220143760A1

公开(公告)日：2022-05-12

申请号：US17436000

申请日：2020-03-26

Applicant: NIPPON STEEL CORPORATION

Inventor： Takashi YASUTOMI ,  Yasuhiro ITO

IPC: B23K33/00 ,  B23K31/02

Abstract: This steel sheet is a steel sheet (100) formed by causing end surfaces of a first sheet material (111) and a second sheet material (113) to abut each other in an in-plane direction and welding the first sheet material (111) and the second sheet material (113) via a strip-shaped welded part (115), and in which a softened part (120) that is softened more than other parts in the welded part (115) is formed in at least a part of the welded part (115), and on a first end surface of the steel sheet in which an end part of the welded part (115) in a longitudinal direction is formed, a region in which the softened part (120) is not formed is provided in at least a part of the end part of the welded part (115) in the longitudinal direction, and a maximum value of a depth of the softened part (120) in a sheet thickness direction is, as a ratio to a sheet thickness of the steel sheet (100), 50% or less.