Global patent index - EP 0903419 A4

EP 0903419 A4 2000-03-22 - THIN STEEL PLATE OF HIGH RECTANGULAR TUBE DRAWABILITY AND METHOD OF MANUFACTURING THE SAME

Title (en)

THIN STEEL PLATE OF HIGH RECTANGULAR TUBE DRAWABILITY AND METHOD OF MANUFACTURING THE SAME

Title (de)

DÜNNES STAHLBLECH MIT HOHER RECHTECKIG-RÖHREZIEHFÄHIGKEIT UND VERFAHREN ZUR HERSTELLUNG DAVON

Title (fr)

TOLE D'ACIER MINCE AYANT UNE APTITUDE ELEVEE A L'EMBOUTISSAGE EN TUBE RECTANGULAIRE, ET PROCEDE DE FABRICATION ASSOCIE

Publication

EP 0903419 A4 (EN)

Application

EP 97913460 A

Priority

  • JP 9704336 W
  • JP 34344996 A

Abstract (en)

[origin: EP0903419A1] A thin steel sheet having excellent rectangular drawability is produced by completing roughing rolling of steel containing C: 0.02 wt% or less, Si: 0.5 wt% or less, Mn: 1.0 wt% or less, P: 0.15 wt% or less, S: 0.02 wt% or less, Al: 0.01 to 0.10 wt%, N: 0.008 wt% or less, at least one of Ti: 0.001 to 0.20 wt% and Nb: 0.001 to 0.15 wt%, the balance comprising Fe, and inevitable impurities, in the temperature region of 950 DEG C to the Ar3 transformation temperature: performing finish rolling at a reduction of over 70% under lubrication in the temperature region of the Ar3 transformation temperature to 500 DEG C; pickling the sheet; annealing the resultant hot rolled sheet under conditions which satisfy the equations (1) and (2) below: <MATH> <MATH> <MATH> wherein T: hot rolled sheet annealing temperature ( DEG C) t: hot rolled sheet annealing time (sec); cold rolling at a reduction of 50 to 95%; and then recrystallization annealing; to satisfy the following relations: <MATH> <MATH> <MATH> wherein rL : Lankford value in the rolling direction, rD : Lankford value in the direction at 45 DEG with the rolling direction, and rC : Lankford value in the direction perpendicular to the rolling direction. <IMAGE>

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

C22C 38/00; C21D 9/48; C22C 38/14

IPC 8 full level (invention and additional information)

C21D 8/04 (2006.01); C22C 38/12 (2006.01); C22C 38/14 (2006.01)

CPC (invention and additional information)

C22C 38/002 (2013.01); C21D 8/0426 (2013.01); C21D 8/0463 (2013.01); C22C 38/004 (2013.01); C22C 38/04 (2013.01); C22C 38/06 (2013.01); C22C 38/12 (2013.01); C22C 38/14 (2013.01); C22C 38/60 (2013.01); C21D 8/0436 (2013.01)

Citation (search report)

  • [XA] EP 0574814 A2 19931222 - KAWASAKI STEEL CO [JP]
  • [XA] PATENT ABSTRACTS OF JAPAN vol. 1995, no. 10 30 November 1995 (1995-11-30)
  • [XA] PATENT ABSTRACTS OF JAPAN vol. 1996, no. 06 28 June 1996 (1996-06-28)
  • See also references of WO 9828457A1

Designated contracting state (EPC)

BE DE ES FR GB

EPO simple patent family

EP 0903419 A1 19990324; EP 0903419 A4 20000322; CN 1083902 C 20020501; CN 1198781 A 19981111; WO 9828457 A1 19980702

INPADOC legal status

2004-06-23 [18D] DEEMED TO BE WITHDRAWN

- Ref Legal Event Code: 18D

- Effective date: 20031223

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

- Owner name: JFE STEEL CORPORATION

- Ref Legal Event Code: RAP1

2002-10-30 [17Q] FIRST EXAMINATION REPORT

- Ref Legal Event Code: 17Q

- Effective date: 20020916

2000-03-22 [A4] SUPPLEMENTARY SEARCH REPORT

- Ref Legal Event Code: A4

- Effective date: 20000208

2000-03-22 [AK] DESIGNATED CONTRACTING STATES:

- Ref Legal Event Code: AK

- Designated State(s): BE DE ES FR GB

1999-03-24 [17P] REQUEST FOR EXAMINATION FILED

- Ref Legal Event Code: 17P

- Effective date: 19980318

1999-03-24 [AK] DESIGNATED CONTRACTING STATES:

- Ref Legal Event Code: AK

- Designated State(s): BE DE ES FR GB