Steel Sheet And Manufacturing Method For Steel Sheet

Abstract: This steel sheet has a predetermined chemical composition and has a metal structure at a 1/4 depth position in which the total area ratio of ferrite and bainite is 0-60%, the area ratio of martensite is 40-100%, and the total area ratio of pearlite and retained austenite is 0-10%, wherein the number density of carbides, containing B and having a minor diameter of at least 0.2 µm, in a surface layer part is at most 0.0030 carbides/µm2.

Patent Information

Application #

Filing Date

02 June 2025

Publication Number

29/2025

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. ISHIKAWA Kyohei

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

2. YOKOYAMA Takafumi

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

3. TAKEDA Kengo

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

Specification

Documents

Application Documents

#	Name	Date
1	202517053341-TRANSLATIOIN OF PRIOIRTY DOCUMENTS ETC. [02-06-2025(online)].pdf	2025-06-02
2	202517053341-STATEMENT OF UNDERTAKING (FORM 3) [02-06-2025(online)].pdf	2025-06-02
3	202517053341-REQUEST FOR EXAMINATION (FORM-18) [02-06-2025(online)].pdf	2025-06-02
4	202517053341-PROOF OF RIGHT [02-06-2025(online)].pdf	2025-06-02
5	202517053341-PRIORITY DOCUMENTS [02-06-2025(online)].pdf	2025-06-02
6	202517053341-POWER OF AUTHORITY [02-06-2025(online)].pdf	2025-06-02
7	202517053341-FORM 18 [02-06-2025(online)].pdf	2025-06-02
8	202517053341-FORM 1 [02-06-2025(online)].pdf	2025-06-02
9	202517053341-DECLARATION OF INVENTORSHIP (FORM 5) [02-06-2025(online)].pdf	2025-06-02
10	202517053341-COMPLETE SPECIFICATION [02-06-2025(online)].pdf	2025-06-02
11	202517053341-FORM-26 [01-08-2025(online)].pdf	2025-08-01
12	202517053341-FORM 3 [24-10-2025(online)].pdf	2025-10-24