Method for producing cold-rolled bands or sheets

US6582537B1 · kind B1 · utility

Assignee

• THYSSEN KRUPP STAHL AG · DE

Inventors

• Bernhard Engl · Dortmund, DE
• Klaus Horn · Dortmund, DE
• Klaus-Dieter Schmidt · Nümbrecht, DE

Key dates

• Filing date: May 1, 2001
• Grant date: Jun 24, 2003
• Expiry date: May 1, 2021

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C21D8/0236
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

The present invention concerns a method for the production of cold-rolled bands or sheets from low-alloy steel with a maximum of 0.2% C, Al, Ti, V, Nb respectively and a maximum of 1% Si and Mn respectively, in addition to a portion of boron required for N binding (>0,78×N), the remainder being constituted by iron and unavoidable impurities, wherein said steel is cast after melting to slabs, thin slabs or a band, which are hot-rolled at a starting temperature above 1100° C. and at a final temperature below Ar3 and wherein the hot band is then drawn and cold-rolled at a temperature below 650° C., whereupon the cold band is annealed independently of the degree of cold-rolling at a low temperature that could possibly vary depending on the composition of the steel and ranging from 520 to 780° C. during a period of time that is sufficiently long to allow for complete recrystallization. The method disclosed makes it possible to simplify manufacturing and to lower production costs associated with the manufacture of a completely recrystallized cold-rolled band or sheet.