Process and device for producing a high-strength steel strip

A process for producing high-strength steel strip comprising:

• casting liquid steel in at least one continuous-casting machine with one or more strands to form a slab having a thickness of less than 150 mm;
• conveying the slab, while utilizing casting heat, through a furnace device;
• preliminarily rolling the slab with a preliminary rolling device, having at least one stand, to form a preliminarily rolled product;
• finish-rolling the preliminarily rolled product in a final rolling device, having at least one stand, to form a steel strip with the desired final thickness,
• wherein the slab undergoes said preliminary rolling in, essentially an austenitic range in the preliminary rolling device and, in the final rolling device rolling the preliminarily rolled product in an austenitic range or, in at least one said stand of the final rolling device, rolling in a two-phase austenitic-ferritic range, said preliminary rolling and said final rolling are both in an endless or semi-endless process;
• and
• rapidly cooling the austenitic or austenitic-ferritic rolled strip, after leaving the final rolling device, in order to obtain a desired temperature.