Abstract: A flat steel product is disclosed which is particularly suitable for the production of components for motor vehicle bodies by press-hardening, and which has insensitivity to cracking coupled with increased strength and has sufficient suitability for welding for incorporation into a welded construction. This combination of properties is achieved in accordance with the invention by virtue of the flat steel product having a core layer consisting of a steel alloyed with Mn, B and at least 0.3% by weight of C and having a tensile strength of more than 1500 MPa, and an outer layer cohesively bonded to the core layer. The C content of the outer layer is not more than 0.09% by weight. This flat steel product has, in the region of the outer layer, a tensile strength corresponding to not more than half the tensile strength of the steel of the core layer in the ready-hardened state, with the elongation A80 of the outer layer corresponding to at least 1.

Abstract: A flat steel product is disclosed which is particularly suitable for the production of components for motor vehicle bodies by press-hardening, and which has insensitivity to cracking coupled with increased strength and has sufficient suitability for welding for incorporation into a welded construction. This combination of properties is achieved in accordance with the invention by virtue of the flat steel product having a core layer consisting of a steel alloyed with Mn, B and at least 0.3% by weight of C and having a tensile strength of more than 1500 MPa, and an outer layer cohesively bonded to the core layer. The C content of the outer layer is not more than 0.09% by weight. This flat steel product has, in the region of the outer layer, a tensile strength corresponding to not more than half the tensile strength of the steel of the core layer in the ready-hardened state, with the elongation A80 of the outer layer corresponding to at least 1.

Abstract: Disclosed is a steel, a steel flat product, a steel part produced from it by hot forming with subsequent hardening, and a method for producing a steel part. In order to guarantee to a high degree of reliability that a part possesses high strength values and an increased elongation at break, the steel contains (in % wt.) C: 0.15-0.40%, Mn: 1.0-2.0%, Al: 0.2-1.6%, Si: 0-1.4%, total of the contents of Si and Al: 0.25-1.6%, P: 0-0.10%, S: 0-0.03%, Cr: 0-0.5%, Mo: 0-1.0%, N: 0-0.01%, Ni: 0-2.0%, Nb: 0.012-0.04%, Ti 0-0.40%, B: 0.0010-0.0050%, Ca: 0-0.0050%, remainder iron and unavoidable impurities.