Method for Producing Thermo-Mechanically Produced Profiled Hot-Rolled Strip Products

A method for producing thermomechanically produced hot strip products, comprising the steps of:

• providing a steel alloy including the following elements, in percent by weight:
• 0.03 to 0.22% carbon,
• 0.0 to 2.0% silicon,
• 0.5 to 3.0% manganese,
• 0.02 to 1.2% aluminum,
• 0 to 2.0% chromium,
• 0 to 2.0% nickel,
• 0.0 to 1.0% molybdenum,
• 0.0 to 1.5% copper,
• 0 to 0.02% phosphorus,
• 0 to 0.01% sulfur,
• 0 to 0.008% nitrogen,
• 0 to 0.005% boron,
• 0.0 to 0.2% niobium,
• 0.0 to 0.3% titanium,
• 0.0 to 0.5% vanadium
• the remainder being comprised of iron and smelting-related impurities;
• melting the steel alloy;
• adjusting the steel alloy so that a recrystallization during hot rolling is suppressed;
• casting the melted steel alloy into slab ingots;
• heating the slab ingots to a temperature above Ac3;
• hot rolling the slab ingots using a final rolling temperature greater than 800° C. until they reach a desired degree of deformation and a desired strip thickness to form steel strips;
• cooling the steel strips to room temperature;
• and
• hardening the steel strips by heating the steel strips to a temperature>Ac3 and cooling the again to form hardened steel strips;
• wherein the heating of the steel strips is performed using a temperature increase of more than 5 K/s and the heated steel strips are kept at a desired target temperature for a holding period of about 0.5 to about 60 seconds prior to coiling hem again;
• and
• the steel alloy has a resulting crystal structure that comprises up to 90% martensite and a remainder of austenite and bainite.