Global Patent Index - EP 3447162 A4

EP 3447162 A4 20191002 - THICK STEEL PLATE

Title (en)

THICK STEEL PLATE

Title (de)

DICKE STAHLPLATTE

Title (fr)

PLAQUE D'ACIER ÉPAISSE

Publication

EP 3447162 A4 20191002 (EN)

Application

EP 17786057 A 20170421

Priority

  • JP 2016085147 A 20160421
  • JP 2016085148 A 20160421
  • JP 2017016090 W 20170421

Abstract (en)

[origin: EP3447162A1] A thick steel plate is provided that has a chemical composition comprising, by mass%, C: 0.01-0.20%, Si: 0.10-0.25%, Mn: 1.30-2.50%, P: 0.01% or less, S: 0.0010-0.0100%, Ti: 0.005-0.030%, Al: 0.003% or less, O: 0.0010-0.0050%, N: 0.0100% or less, Cu: 0-0.50%, Ni: 0-1.50%, Cr: 0-0.50%, Mo: 0-0.50%, V: 0-0.10%, Nb: 0-0.05%, and the balance: Fe and impurities, and which contains in the steel a composite inclusion in which MnS is present around a Ti oxide. An area fraction of MnS in a cross-section of the composite inclusion is 10% or more and less than 90%, the proportion which MnS accounts for in the peripheral length of the composite inclusion is 10% or more, and the number density of composite inclusions that have a grain diameter in a range of 0.5-5.0 µm is in a range of 10-100 per mm 2 . The thick steel plate exhibits excellent HAZ low-temperature properties during high heat input welding.

IPC 8 full level

C22C 38/00 (2006.01); C21D 8/02 (2006.01); C22C 38/02 (2006.01); C22C 38/04 (2006.01); C22C 38/06 (2006.01); C22C 38/08 (2006.01); C22C 38/14 (2006.01); C22C 38/16 (2006.01); C22C 38/18 (2006.01); C22C 38/58 (2006.01)

CPC (source: EP KR)

C21D 8/0226 (2013.01 - EP); C21D 8/0263 (2013.01 - EP); C22C 38/001 (2013.01 - EP); C22C 38/02 (2013.01 - EP KR); C22C 38/04 (2013.01 - EP KR); C22C 38/06 (2013.01 - EP); C22C 38/08 (2013.01 - EP); C22C 38/14 (2013.01 - EP KR); C22C 38/16 (2013.01 - EP KR); C22C 38/18 (2013.01 - EP)

Citation (search report)

Designated contracting state (EPC)

AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

DOCDB simple family (publication)

EP 3447162 A1 20190227; EP 3447162 A4 20191002; EP 3447162 B1 20201230; CN 109072383 A 20181221; CN 109072383 B 20210209; KR 20180132909 A 20181212; WO 2017183720 A1 20171026

DOCDB simple family (application)

EP 17786057 A 20170421; CN 201780024463 A 20170421; JP 2017016090 W 20170421; KR 20187033428 A 20170421