Steel Sheet And Plated Steel Sheet

Abstract: Provided is a steel sheet comprising 0.05-0.40% C, 0.2-3.0% Si, and 0.1-5.0% Mn, in mass%, wherein: the surface layer of the steel sheet contains a grain-boundary-type oxide; the ratio A of the length of the grain-boundary-type oxide projected on the surface of the steel sheet to the length of the surface of the steel sheet is 50-100%; the number density of grain-type oxide is less than 4.0/µm2; a Si-Mn deficient layer having a thickness of not less than 3.0 µm from the surface of the steel sheet is included; and the Si content and the Mn content in the Si-Mn deficient layer not including an oxide at position at half the thickness are less than 10% of the Si content and the Mn content, respectively, at the sheet-thickness-wise center part of the steel sheet. Also provided is a plated steel sheet using the steel sheet.

Patent Information

Application #

Filing Date

25 October 2023

Publication Number

36/2024

Publication Type

INA

Invention Field

METALLURGY

Status

Email

Parent Application

Applicants

NIPPON STEEL CORPORATION

6-1, Marunouchi 2-chome, Chiyoda-ku, Tokyo 1008071

Inventors

1. MATSUDA, Keitaro

c/o NIPPON STEEL CORPORATION, 6-1, Marunouchi 2-chome, Chiyoda-ku, Tokyo 1008071

2. MITSUNOBU, Takuya

c/o NIPPON STEEL CORPORATION, 6-1, Marunouchi 2-chome, Chiyoda-ku, Tokyo 1008071

3. MAKI, Jun

c/o NIPPON STEEL CORPORATION, 6-1, Marunouchi 2-chome, Chiyoda-ku, Tokyo 1008071

4. TAKEBAYASHI, Hiroshi

c/o NIPPON STEEL CORPORATION, 6-1, Marunouchi 2-chome, Chiyoda-ku, Tokyo 1008071

Specification

Documents

Application Documents

#	Name	Date
1	202317072656-TRANSLATIOIN OF PRIOIRTY DOCUMENTS ETC. [25-10-2023(online)].pdf	2023-10-25
2	202317072656-STATEMENT OF UNDERTAKING (FORM 3) [25-10-2023(online)].pdf	2023-10-25
3	202317072656-REQUEST FOR EXAMINATION (FORM-18) [25-10-2023(online)].pdf	2023-10-25
4	202317072656-PROOF OF RIGHT [25-10-2023(online)].pdf	2023-10-25
5	202317072656-POWER OF AUTHORITY [25-10-2023(online)].pdf	2023-10-25
6	202317072656-FORM 18 [25-10-2023(online)].pdf	2023-10-25
7	202317072656-FORM 1 [25-10-2023(online)].pdf	2023-10-25
8	202317072656-DRAWINGS [25-10-2023(online)].pdf	2023-10-25
9	202317072656-DECLARATION OF INVENTORSHIP (FORM 5) [25-10-2023(online)].pdf	2023-10-25
10	202317072656-COMPLETE SPECIFICATION [25-10-2023(online)].pdf	2023-10-25
11	202317072656-FORM 3 [13-02-2024(online)].pdf	2024-02-13