Title:
THICK STEEL SHEET AND MANUFACTURING METHOD FOR SAME
Document Type and Number:
WIPO Patent Application WO/2023/002812
Kind Code:
A1
Abstract:
A steel sheet comprising 0.04-0.16 mass% of C, 0.10-0.50 mass% of Si, 0.60-1.60 mass% of Mn, 0.005-0.030 mass% of P, 0.015-0.050 mass% of Al, 0.005-0.020 mass% of Ti, 0.0005-0.0025 mass% of Ca, 0.0008-0.0025 mass% of O, 0.0005-0.0020 mass% of B, and 0.0030-0.0060 mass% of N, the remaining portion being Fe and unavoidable impurities, wherein the steel sheet satisfies formulae (1) and (2), and has a metal structure in which ferrite and perlite are contained at 90% or more in area ratio, and in which the remaining portion is island martensite and/or bainite, and the difference between the upper yield point and the lower yield point of the steel sheet is 30 MPa or less. (1): 3[Si]+6.3[P]+1.4[Al]≥0.63
(2): [Ca]/[O]≥0.2
Inventors:
TABATA AKITO
TASHIRO KIICHIRO
TASHIRO KIICHIRO
Application Number:
PCT/JP2022/025748
Publication Date:
January 26, 2023
Filing Date:
June 28, 2022
Export Citation:
Assignee:
KOBE STEEL LTD (JP)
International Classes:
C21D8/02; C22C38/00; C22C38/14; C22C38/58
Domestic Patent References:
| WO2021106368A1 | 2021-06-03 |
Foreign References:
| CN103866194A | 2014-06-18 | |||
| JP2008274360A | 2008-11-13 | |||
| EP1154028A1 | 2001-11-14 |
Attorney, Agent or Firm:
YAMAO, Norihito (JP)
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