Steel Sheet And Method For Producing Same

Abstract: A steel sheet having a prescribed chemical composition and having a metal structure which comprises ferrite, bainite and pearlite in a combined total of 0-50 vol%, inclusive, and retained austenite in the amount of 3-20 vol%, inclusive, with the remainder constituting fresh martensite and tempered martensite, wherein: retained austenite which has an aspect ratio of 3.0 or higher constitutes at least 80%, as an area ratio, of the total retained austenite; an internal oxidation layer is present which has a thickness of at least 4.0µm from the surface of the steel sheet, a decarburized layer is present which has a thickness of 10-100µm, inclusive, from the surface of the steel sheet; and the diffusible hydrogen content contained in the steel sheet constitutes 1.00ppm or less by mass.

Patent Information

Application #

Filing Date

28 April 2023

Publication Number

47/2023

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. TSUKAMOTO Eriko

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

2. TAKEDA Kengo

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

Specification

Documents

Application Documents

#	Name	Date
1	202317030627-TRANSLATIOIN OF PRIOIRTY DOCUMENTS ETC. [28-04-2023(online)].pdf	2023-04-28
2	202317030627-STATEMENT OF UNDERTAKING (FORM 3) [28-04-2023(online)].pdf	2023-04-28
3	202317030627-REQUEST FOR EXAMINATION (FORM-18) [28-04-2023(online)].pdf	2023-04-28
4	202317030627-PROOF OF RIGHT [28-04-2023(online)].pdf	2023-04-28
5	202317030627-PRIORITY DOCUMENTS [28-04-2023(online)].pdf	2023-04-28
6	202317030627-POWER OF AUTHORITY [28-04-2023(online)].pdf	2023-04-28
7	202317030627-FORM 18 [28-04-2023(online)].pdf	2023-04-28
8	202317030627-FORM 1 [28-04-2023(online)].pdf	2023-04-28
9	202317030627-DRAWINGS [28-04-2023(online)].pdf	2023-04-28
10	202317030627-DECLARATION OF INVENTORSHIP (FORM 5) [28-04-2023(online)].pdf	2023-04-28
11	202317030627-COMPLETE SPECIFICATION [28-04-2023(online)].pdf	2023-04-28
12	202317030627.pdf	2023-05-03
13	202317030627-FORM 3 [20-09-2023(online)].pdf	2023-09-20
14	202317030627-FER.pdf	2025-10-06

Search Strategy

1	202317030627_SearchStrategyNew_E_SearchHistoryE_03-10-2025.pdf