Title:
HIGH-STRENGTH STEEL PLATE HAVING EXCELLENT FORMABILITY, TOUGHNESS AND WELDABILITY, AND PRODUCTION METHOD OF SAME
Document Type and Number:
WIPO Patent Application WO/2020/121417
Kind Code:
A1
Abstract:
This high-strength steel plate has excellent formability, toughness and weldability, and is characterized in that the component composition has, in mass%, C: 0.05-0.30%, Si: 2.50% or less, Mn: 0.50-3.50%, P: 0.100% or less, S: 0.0100% or less, Al: 0.001-2.500%, N: 0.0150% or less, and O: 0.0050% or less, the remainder being Fe and unavoidable impurities, wherein the microstructure of the region from 1/8t (t: plate thickness) to 3/8t (t: plate thickness) from the surface of the steel plate contains, in vol%, at least 20% acicular ferrite and at least 10% martensite (4), and is limited to no more than 20% globular ferrite and no more than 2.0% retained austenite, and the martensite satisfies expression (A).
Inventors:
KAWATA HIROYUKI (JP)
SAKURADA EISAKU (JP)
SANO KOHICHI (JP)
YOKOYAMA TAKAFUMI (JP)
SAKURADA EISAKU (JP)
SANO KOHICHI (JP)
YOKOYAMA TAKAFUMI (JP)
Application Number:
PCT/JP2018/045547
Publication Date:
June 18, 2020
Filing Date:
December 11, 2018
Export Citation:
Assignee:
NIPPON STEEL CORP (JP)
International Classes:
C22C38/00; B21B3/00; C21D9/46; C22C38/06; C22C38/60; C25D5/26; C25D5/50
Domestic Patent References:
| WO2017169329A1 | 2017-10-05 |
Foreign References:
| JP2009127065A | 2009-06-11 | |||
| JP2013019047A | 2013-01-31 | |||
| JPH1150186A | 1999-02-23 | |||
| JP2004238679A | 2004-08-26 | |||
| JP2004323958A | 2004-11-18 | |||
| JP2006274318A | 2006-10-12 | |||
| JP2008297609A | 2008-12-11 | |||
| JP2011225941A | 2011-11-10 | |||
| JP2012026032A | 2012-02-09 | |||
| JP2011195956A | 2011-10-06 | |||
| JP2013181208A | 2013-09-12 |
Other References:
See also references of EP 3896185A4
Attorney, Agent or Firm:
KINOSHITA & ASSOCIATES (JP)
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