Global Patent Index - EP 3495522 A1

EP 3495522 A1 20190612 - HIGH-STRENGTH STEEL PLATE AND MANUFACTURING METHOD THEREOF

Title (en)

HIGH-STRENGTH STEEL PLATE AND MANUFACTURING METHOD THEREOF

Title (de)

HOCHFESTE STAHLPLATTE UND HERSTELLUNGSVERFAHREN DAFÜR

Title (fr)

PLAQUE D'ACIER À HAUTE RÉSISTANCE ET SON PROCÉDÉ DE FABRICATION

Publication

EP 3495522 A1 20190612 (EN)

Application

EP 17836780 A 20170721

Priority

  • JP 2016153107 A 20160803
  • JP 2017026557 W 20170721

Abstract (en)

Disclosed is a high-strength sheet including: C: 0.15% to 0.35% by mass, total of Si and Al: 0.5% to 3.0% by mass, Mn: 1.0% to 4.0% by mass, P: 0.05% by mass or less, and S: 0.01% by mass or less, with the balance being Fe and inevitable impurities, wherein the steel structure satisfies that: a ferrite fraction is 5% or less, the total fraction of tempered martensite and tempered bainite is 60% or more, the amount of retained austenite is 10% or more, MA has an average size of 1.0 µm or less, retained austenite has an average size of 1.0 µm or less, retained austenite having a size of 1.5 µm or more accounts for 2% or more of the total amount of retained austenite, and a scattering intensity at the q value of 1 nmin X-ray small angle scattering is 1.0 cmor less.

IPC 8 full level

C22C 38/00 (2006.01); C21D 1/18 (2006.01); C21D 9/46 (2006.01); C22C 38/06 (2006.01)

CPC (source: EP US)

C21D 1/18 (2013.01 - US); C21D 1/19 (2013.01 - EP); C21D 1/20 (2013.01 - EP); C21D 1/25 (2013.01 - EP); C21D 1/34 (2013.01 - US); C21D 6/005 (2013.01 - US); C21D 6/008 (2013.01 - US); C21D 8/0473 (2013.01 - EP); C21D 9/46 (2013.01 - US); C21D 9/48 (2013.01 - EP); C22C 38/00 (2013.01 - US); C22C 38/002 (2013.01 - US); C22C 38/02 (2013.01 - EP US); C22C 38/04 (2013.01 - EP US); C22C 38/06 (2013.01 - EP US); C21D 2211/001 (2013.01 - EP US); C21D 2211/002 (2013.01 - EP US); C21D 2211/008 (2013.01 - EP US)

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

Designated extension state (EPC)

BA ME

DOCDB simple family (publication)

EP 3495522 A1 20190612; EP 3495522 A4 20200226; EP 3495522 B1 20210901; CN 109477181 A 20190315; CN 109477181 B 20201009; JP 2018021231 A 20180208; JP 6762797 B2 20200930; US 2019218640 A1 20190718; WO 2018025674 A1 20180208

DOCDB simple family (application)

EP 17836780 A 20170721; CN 201780046030 A 20170721; JP 2016153107 A 20160803; JP 2017026557 W 20170721; US 201716321544 A 20170721