Global Patent Index - EP 1319725 A2

EP 1319725 A2 2003-06-18 - Hot strip manufacturing process

Title (en)

Hot strip manufacturing process

Title (de)

Verfahren zum Herstellen von Warmband

Title (fr)

Procédé pour la fabrication d'une bande à chaud

Publication

EP 1319725 A2 (DE)

Application

EP 02025150 A

Priority

DE 10161465 A

Abstract (en)

Production of a hot strip having a tensile strength of at least 800 N/mm<2> comprises casting a steel into a pre-material, such as thin slabs or cast strip; hot rolling the pre-material at a final temperature lying above the Ar3 temperature to form a hot strip; cooling in a first cooling step at a cooling speed of at least 150 K/s to 500-700 degrees C; and cooling in a second cooling step after a 3-10 seconds cooling pause to a coiling temperature. The coiling temperature is more than 580 degrees C for hot strips having a yield point of more than 690 MPa and a tensile strength of less than 900 MPa. The coiling temperature is 580 degrees C or less for hot strips having a yield point of not more than 690 MPa and a tensile strength of less than 900 MPa. The coiling temperature is not more than 250 degrees C for hot strips having a tensile strength of less than 900 MPa. <??>The steel contains (in wt.%): 0.03-0.10 C, not more than 0.8 Si, 1.2-2.0 Mn, 0.02-0.06 Al, not more than 0.5 Cr, not more than 0.2 Ti, not more than 0.08 Nb, less than 0.005 Ca, less than 0.05 Cu, less than 0.05 Ni, less than 0.02 P, less than 0.005 S, less than 0.01 N and a balance of Fe. <??>Preferred Features: The steel contains 0.05-0.07 wt.% C and 0.3-0.8 wt.% Si.

Abstract (de)

Das erfindungsgemäße Verfahren ermöglicht auf kostengünstig durchführbare Weise, die Eigenschaften von hochfestem, gut verformbarem Warmband auf den jeweiligen Verwendungszweck hin gezielt zu optimieren. Dabei wird ein Stahl verarbeitet, der niedrige, unter-peritektische Gehalte an Kohlenstoff besitzt. Dieser Stahl wird zu Dünnbrammen oder Band vergossen, mit einer mindestens 150 K betragen Abkühlgeschwindigkeit auf eine zwischen 500 °C und 700 °C liegenden Zwischentemperatur abgekühlt und gehaspelt. Durch die Wahl der Haspeltemperatur lassen sich dann die Eigenschaften des erhaltenen Warmbands gezielt einstellen.

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

C21D 8/02; C22C 38/06

IPC 8 full level (invention and additional information)

C21D 8/02 (2006.01)

CPC (invention and additional information)

C21D 8/0226 (2013.01); C21D 8/021 (2013.01); C21D 8/0221 (2013.01); C21D 8/0263 (2013.01); C21D 8/0278 (2013.01)

Designated contracting state (EPC)

AT BE BG CH CY CZ DE DK EE ES FI FR GB GR IE IT LI LU MC NL PT SE SK TR

DOCDB simple family

DE 10161465 C1 20030213; AT 280248 T 20041115; EP 1319725 A2 20030618; EP 1319725 A3 20031210; EP 1319725 B1 20041020; ES 2231638 T3 20050516