Hot Rolled Steel Sheet

Abstract: This hot-rolled steel sheet has a prescribed chemical composition, and GAMS/GAMI is 0.70-1.05. In the metal structure at a position at 1/4 depth from the surface in the sheet thickness direction, the area ratio of a region in which the GAM value is greater than 0.6° is 50% or higher, the total of the area ratio of a region in which the GAM value is greater than 3.0° and the area ratio of retained austenite is less than 15%, and the standard deviation of the area average value of the GAM value of the crystal grains in a region from the surface to a depth of 200 µm in the sheet thickness direction is 0.25-0.65°.

Patent Information

Application #

Filing Date

09 July 2025

Publication Number

32/2025

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. YASUTOMI Takashi

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

2. HATTORI Tatsuhiro

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

3. AZUMA Masafumi

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

Specification

Documents

Application Documents

#	Name	Date
1	202517065520-TRANSLATIOIN OF PRIOIRTY DOCUMENTS ETC. [09-07-2025(online)].pdf	2025-07-09
2	202517065520-STATEMENT OF UNDERTAKING (FORM 3) [09-07-2025(online)].pdf	2025-07-09
3	202517065520-REQUEST FOR EXAMINATION (FORM-18) [09-07-2025(online)].pdf	2025-07-09
4	202517065520-PROOF OF RIGHT [09-07-2025(online)].pdf	2025-07-09
5	202517065520-PRIORITY DOCUMENTS [09-07-2025(online)].pdf	2025-07-09
6	202517065520-POWER OF AUTHORITY [09-07-2025(online)].pdf	2025-07-09
7	202517065520-FORM 18 [09-07-2025(online)].pdf	2025-07-09
8	202517065520-FORM 1 [09-07-2025(online)].pdf	2025-07-09
9	202517065520-DRAWINGS [09-07-2025(online)].pdf	2025-07-09
10	202517065520-DECLARATION OF INVENTORSHIP (FORM 5) [09-07-2025(online)].pdf	2025-07-09
11	202517065520-COMPLETE SPECIFICATION [09-07-2025(online)].pdf	2025-07-09