Method for producing a flat steel product which can be readily formed, flat steel product and method for producing a component from such a flat steel product

US9234253B2 · kind B2 · utility

Assignee

• ThyssenKrupp Steel Europe AG · DE

Inventors

• Wilhelm Warnecke · Hamminkeln, DE
• Manfred Meurer · Rheinberg, DE
• Jens Kondratiuk · Buchs, CH
• Marc Blumenau · Hagen, DE
• Martin Norden · Essen, DE
• Thiemo Wuttke · Recklinghausen, DE

Key dates

• Filing date: Dec 3, 2010
• Grant date: Jan 12, 2016
• Expiry date: Sep 14, 2032

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C22C38/38
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

A readily formable flat steel product has a ductile edge layer that is from 10 to 200 μm thick and has a ductility greater than a ductility of an inner core layer of the flat steel product. The readily formable flat steel product is produced by annealing a flat steel product having a C content of from 0.1 to 0.4% by weight in a continuous furnace. The annealing is carried out under an annealing atmosphere that contains from 0.1 to 25% by vol. of H2 and H2O, with the balance being N2 and technically unavoidable impurities. A dew point is between −20° C. and +60° C., and a ratio of H2O/H2 is a maximum of 0.957. In the course of the annealing, the flat steel product is heated to a holding temperature of from 600 to 1100° C. and for a holding time of from 10 to 360 seconds.