公开(公告)号：US20210197525A1

公开(公告)日：2021-07-01

申请号：US16613981

申请日：2019-04-05

Applicant: NIPPON STEEL CORPORATION

Inventor： Soshi FUJITA ,  Yuki SUZUKI ,  Masahiro FUDA ,  Jun MAKI ,  Hideaki IRIKAWA ,  Masahiro NAKATA

IPC: B32B15/01 ,  C23C2/12 ,  B21D22/02 ,  B23K31/02

Abstract: To solve the problem about the difference in temperature increasing rate between an overlapped part and a one-sheet part so as to further improve the corrosion resistance of plating after hot stamping. An overlapped blank for hot stamping includes: a first steel sheet; and at least one second steel sheet connected to a surface of the first steel sheet via a welding point and smaller in area than the first steel sheet, wherein: the first steel sheet is a plated steel sheet having an aluminum-based plated layer on both faces of the first steel sheet, and the second steel sheet is a plated steel sheet having an aluminum-based plated layer on both faces of the second steel sheet; a coating weight of the aluminum-based plated layer on the first steel sheet is W1 (g/m2) in terms of an average coating weight on both the faces; a coating weight of the aluminum-based plated layer on a surface on a side not in contact with the first steel sheet in the second steel sheet is W2 (g/m2); and each of the W1 and the W2 is within a range of 20 g/m2 or more and 120 g/m2 or less, and satisfies relationships of Expression (1) and Expression (2).

公开(公告)号：US20210164080A1

公开(公告)日：2021-06-03

申请号：US16768869

申请日：2018-12-05

Applicant: NIPPON STEEL CORPORATION

Inventor： Soshi FUJITA ,  Yuki SUZUKI ,  Masahiro FUDA ,  Jun MAKI ,  Hideaki IRIKAWA ,  Takashi ARAMAKI ,  Tatsuya KUBOTA

IPC: C22C38/54 ,  C23C2/12 ,  C22C38/50 ,  C22C38/48 ,  C22C38/44 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C23C2/40 ,  C21D9/46 ,  C21D8/02 ,  C21D9/00

Abstract: An aluminum-based plated steel sheet according to an aspect of the present invention includes: a base material; an aluminum-based plating layer located above the base material; and an intermetallic compound layer that is located between the base material and the aluminum-based plating layer and contains an intermetallic compound of Al and Fe, in which the base material has a chemical component within a predetermined range, the aluminum-based plating layer contains, on average, 80 mass % or more and 97 mass % or less of Al, 3 mass % or more and 15 mass % or less of Si, 0 mass % or more and 5 mass % or less of Zn, 0 mass % or more and 5 mass % or less of Fe, 0 mass % or more and 3 mass % or less in total of one or more selected from the group consisting of Mg and Ca, and impurities so that a total amount thereof is 100 mass %, an average value of a thickness of the intermetallic compound layer is 2 μm or more and 10 μm or less, a maximum value of the thickness of the intermetallic compound layer is 10 μm or more and 25 μm or less, and a standard deviation of the thickness of the intermetallic compound layer is 2 μm or more and 10 μm or less.

公开(公告)号：US20210114074A1

公开(公告)日：2021-04-22

申请号：US17044194

申请日：2019-04-09

Applicant: NIPPON STEEL CORPORATION

Inventor： Masahiro KUBO ,  Soshi FUJITA ,  Yoshiaki NAKAZAWA ,  Hideaki IRIKAWA ,  Masahiro FUDA

IPC: B21D22/02 ,  C21D1/673 ,  B32B15/01

Abstract: A method of producing a hot press-formed product includes subjecting an Al-plated steel sheet having a zinc compound layer or a metallic zinc layer, as an outermost layer, provided on an Al plating layer to hot press forming using a die. The die includes a hard layer having a skewness (Rsk), as measured in a direction from the outside of a die hole toward the inside of the die hole, of 1.3 or less and a hardness Hv_Die of HV 2,000 or more, over the entirety of a region of a steel sheet contact surface that is adjacent to a die shoulder portion. The steel sheet contact surface is a surface located outside of the die hole and configured to contact the Al-plated steel sheet that is to be subjected to the hot press forming.

公开(公告)号：US20200238357A1

公开(公告)日：2020-07-30

申请号：US16651229

申请日：2018-09-28

Applicant: NIPPON STEEL CORPORATION

Inventor： Masahiro KUBO ,  Yoshiaki NAKAZAWA ,  Toshiya SUZUKI ,  Naruhiko NOMURA ,  Soshi FUJITA ,  Hideaki IRIKAWA ,  Masahiro FUDA

IPC: B21D22/20 ,  B32B15/04 ,  B21D24/04 ,  C23C2/12 ,  B32B9/04

Abstract: Provided is a coated steel sheet including a steel sheet, a first aluminum coating layer provided on a first surface of the steel sheet, a zinc compound layer or a metallic zinc layer provided on a surface of the first aluminum coating layer, and a second aluminum coating layer provided on a second surface of the steel sheet, as an outermost surface of the steel sheet. Further provided are a coated steel sheet coil using this coated steel sheet, and a method of producing a hot-press formed article, as well as an automobile part using a press formed article produced by the method of producing a hot-press formed article.