Global patent index - EP 1029938 A2

EP 1029938 A2 2000-08-23 - Rolled steel having few inclusion defects

Title (en)

Rolled steel having few inclusion defects

Title (de)

Gewalztes Stahl mit wenigen Einschlüssfehlern

Title (fr)

Acier laminé ayant peu de défauts d'inclusions

Publication

EP 1029938 A2 (EN)

Application

EP 00102280 A

Priority

  • JP 3964799 A
  • JP 10980599 A

Abstract (en)

The present invention provides rolled steel having few inclusion defects suitable for steel sheets used for automobiles, steel sheets used for deeply drawn cans and steel pipes, the basic composition of which is C: 0.0002 to 0.7 mass %, Si: 0.001 to 0.5 mass %, Mn: 0.005 to 2.0 mass %, P: 0.001 to 0.05 mass %, S: 0.0005 to 0.15 mass %, Ti: 0.001 to 0.25 mass % and dissolved Al: 0.001 to 0.1 mass %, the selective composition of which is Ca: not more than 50 ppm and Mg: not more than 50 ppm, at least one of Ca and Mg being contained, wherein created oxide inclusions are mainly composed of one of the crystallized phase, the principal component of which is titanium oxide, and the crystallized phase, the principal component of which is alumina, and further composed of at least one of the crystallized phase, the principal component of which is CaO, and the crystallized phase, the principal component of which is MgO, and the crystallized phases of oxide inclusions exist in steel.

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

C22C 38/14; C21D 8/02

IPC 8 full level (invention and additional information)

C22C 38/00 (2006.01); C22C 38/04 (2006.01); C22C 38/06 (2006.01); C22C 38/14 (2006.01)

CPC (invention and additional information)

C22C 38/004 (2013.01); C22C 38/04 (2013.01); C22C 38/06 (2013.01); C22C 38/14 (2013.01)

Designated contracting state (EPC)

AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE

EPO simple patent family

EP 1029938 A2 20000823; EP 1029938 A3 20031015

INPADOC legal status

2004-03-24 [18D] DEEMED TO BE WITHDRAWN

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- Effective date: 20030224

2003-10-15 [AK] DESIGNATED CONTRACTING STATES:

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- Designated State(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE

2003-10-15 [AX] REQUEST FOR EXTENSION OF THE EUROPEAN PATENT TO

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- Extension state: AL LT LV MK RO SI

2000-08-23 [17P] REQUEST FOR EXAMINATION FILED

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- Effective date: 20000316

2000-08-23 [AK] DESIGNATED CONTRACTING STATES:

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- Designated State(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE

2000-08-23 [AX] REQUEST FOR EXTENSION OF THE EUROPEAN PATENT TO

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- Free Format Text: AL;LT;LV;MK;RO;SI