Global Patent Index - EP 1350859 B1

EP 1350859 B1 2004-12-29 - High-tensile strength hot-rolled steel sheet excellent in elongation properties and stretch flangeability, and producing method thereof

Title (en)

High-tensile strength hot-rolled steel sheet excellent in elongation properties and stretch flangeability, and producing method thereof

Title (de)

Zugfestes warmgewalztes Stahlblech mit ausgezeichneter Bruchdehnung und Streckbördelverformfähigheit und dessen Herstellungsverfahren

Title (fr)

Tôle d'acier laminée à chaud résistant à la traction, ayant une allongement et une déformabilité de bordage par étirage excellente et son procédé de fabrication

Publication

EP 1350859 B1 (EN)

Application

EP 03006195 A

Priority

  • JP 2002081451 A
  • JP 2003039099 A

Abstract (en)

[origin: EP1350859A1] A high-tensile strength hot-rolled steel sheet that satisfies, in addition to TS of 780 MPa or more or furthermore 980 MPa or more, TS X EL 20000 MPa% and TS x lambda 82000 MPa%, and a method of producing the same are provided. Specific resolution means are as follows. That is, a high-tensile strength hot-rolled steel sheet including a composition that includes C of 0.04% by mass or more and 0.25% by mass or less; Si of 0.4% by mass or more and 2.0% by mass or less; Mn of 3.0% by mass or less; Al of 0.2% by mass or less; S of 0.007% by mass or less; Ti of 0.08% by mass or more and 0.3% by mass or less; and the balance of Fe and inevitable impurities, in the above, the contents of the C, the Si and the Ti satisfing (Ä%CÜ/12 - Ä%TiÜ/48)/(Ä%SiÜ/28) 0.4; and a microstructure that includes ferrite; bainite; and retained austenite; in the above a fraction of the ferrite in an entire microstructure is 40% or more and an average grain size of the ferrite is 5 mu m or less; a fraction of the bainite is in the range of 20% to 48% with respect to an entire microstructure; and a fraction of the retained austenite is in the range of 2% to 7% with respect to an entire microstructure is produced.

IPC 1-7 (main, further and additional classification)

C22C 38/14; C21D 8/02; C21D 8/04; C22C 38/58

IPC 8 full level (invention and additional information)

B21B 1/22 (2006.01); B21B 3/00 (2006.01); C21D 8/02 (2006.01); C21D 9/46 (2006.01); C22C 38/00 (2006.01); C22C 38/02 (2006.01); C22C 38/04 (2006.01); C22C 38/14 (2006.01)

CPC (invention and additional information)

C21D 8/0263 (2013.01); C21D 8/0226 (2013.01); C22C 38/02 (2013.01); C22C 38/04 (2013.01); C22C 38/14 (2013.01); C21D 2211/001 (2013.01); C21D 2211/002 (2013.01); C21D 2211/005 (2013.01)

Designated contracting state (EPC)

DE FR

EPO simple patent family

EP 1350859 A1 20031008; EP 1350859 B1 20041229; CN 1296507 C 20070124; CN 1450191 A 20031022; DE 60300242 D1 20050203; DE 60300242 T2 20050602; JP 2004002969 A 20040108; JP 4062118 B2 20080319; KR 100778264 B1 20071122; KR 20030076430 A 20030926

INPADOC legal status


2017-04-28 [PGFP DE] POSTGRANT: ANNUAL FEES PAID TO NATIONAL OFFICE

- Ref Country Code: DE

- Payment date: 20170314

- Year of fee payment: 15

2011-01-31 [PG25 FR] LAPSED IN A CONTRACTING STATE ANNOUNCED VIA POSTGRANT INFORM. FROM NAT. OFFICE TO EPO

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- Free text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

- Effective date: 20100331

2010-12-24 [REG FR ST] NOTIFICATION OF LAPSE

- Effective date: 20101130

2009-10-30 [PGFP FR] POSTGRANT: ANNUAL FEES PAID TO NATIONAL OFFICE

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- Payment date: 20090316

- Year of fee payment: 7

2005-12-30 [ET] FR: TRANSLATION FILED

2005-12-21 [26N] NO OPPOSITION FILED

- Effective date: 20050930

2005-02-03 [REF] CORRESPONDS TO:

- Document: DE 60300242 P 20050203

2005-01-26 [REG IE FG4D] EUROPEAN PATENTS GRANTED DESIGNATING IRELAND

2004-12-29 [AK] DESIGNATED CONTRACTING STATES:

- Kind Code of Ref Document: B1

- Designated State(s): DE FR

2004-06-30 [AKX] PAYMENT OF DESIGNATION FEES

- Designated State(s): DE FR

2004-01-28 [17P] REQUEST FOR EXAMINATION FILED

- Effective date: 20031201

2003-12-03 [RAP1] TRANSFER OF RIGHTS OF AN EP PUBLISHED APPLICATION

- Owner name: JFE STEEL CORPORATION

2003-10-08 [AK] DESIGNATED CONTRACTING STATES:

- Kind Code of Ref Document: A1

- Designated State(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LI LU MC NL PT SE SI SK TR

2003-10-08 [AX] REQUEST FOR EXTENSION OF THE EUROPEAN PATENT TO

- Countries: AL LT LV MK RO