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: Methods for producing a flat product from an iron-based shape memory alloy may involve casting a melt comprised of iron, alloying elements, and impurities into a strip having a thickness of 1-30 mm and cooling the melt as the strip is formed. A twin-roll caster may be employed to help cool and form the melt into the strip. The resultant flat product is highly resistant to bending and is robust under pressure and torsion.

Abstract: A bipolar plate which can be produced particularly economically for a fuel cell, with which a high degree of efficiency is guaranteed over a long service life. The bipolar plate has a core layer consisting of a steel material, the surfaces of said core layer, which are associated with the respective electrolyte carriers of the fuel cell, having a corrosion protection layer, protecting the core layer against corrosion. The corrosion protection layers consist of a metal material and extend on both sides over the whole surface of the core layer. At the same time the corrosion protection layers are in turn coated over the whole surface with an electrically conductive functional coating, which is essentially entirely impermeable for the metal ions emerging from the core layer and/or the corrosion protection layers. The invention likewise relates to at least one fuel cell comprising a bipolar plate according to the invention.

Abstract: A flat steel product having a tensile strength of at least 1200 MPa and consists of steel containing (wt %) C: 0.10-0.50%, Si: 0.1-2.5%, Mn: 1.0-3.5%, Al: up to 2.5%, P: up to 0.020%, S: up to 0.003%, N: up to 0.02%, and optionally one or more of the elements “Cr, Mo, V, Ti, Nb, B and Ca” in the quantities: Cr: 0.1-0.5%, Mo: 0.1-0.3%, V: 0.01-0.1%, Ti: 0.001-0.15%, Nb: 0.02-0.05%, wherein ?(V, Ti, Nb)?0.2% for the sum of the quantities of V, Ti and Nb, B: 0.0005-0.005%, and Ca: up to 0.01% in addition to Fe and unavoidable impurities. The flat steel product has a microstructure with (in surface percent) less than 5% ferrite, less than 10% bainite, 5-70% untempered martensite, 5-30% residual austenite, and 25-80% tempered martensite, at least 99% of the iron carbide contained in the tempered martensite having a size of less than 500 nm.

Abstract: A composite material with a ballistic protective effect having a first, outer layer made of a first steel alloy and at least one second layer which is arranged under the first layer and is made of a second steel alloy. The composite material with a ballistic protective effect allows for a reduction in the weight or the wall thicknesses of the composite material in comparison to conventional composite ballistic materials, by utilizing a first steel alloy of the first layer that has the following alloy constituents in percent by weight (% by weight): 0.06%?C ?1.05%, 0.05%?Si?1.65%, 0.3%?Mn?2.65%, 0.015%?Al?1.55%; Cr?1.2%, Ti?0.13%, Mo?0.7%, Nb?0.1%, B?0.005%, P?0.08%, S?0.01%, Ni?4.0%, and V?0.05%, the remainder being Fe and inevitable impurities. The second layer of the composite material having a higher elongation than the first layer.

Abstract: A use of a coilable multi-layer metallic composite material produced by means of roll-cladding in a vehicle structure, in particular a body structure, provides an alternative to monolithic materials. The composite material used in a vehicle structure is a lightweight composite material and comprises three layers of a steel alloy, wherein at least one of the layers is formed from a high-strength or very high-strength steel alloy.

Abstract: High-strength, cold-formable steel and a flat steel product produced from such a steel, in which an optimal combination of weldability and a low tendency towards delayed cracking is ensured along with good strength and hot and cold deformability. In order to achieve this, a steel according to the invention contains (in % by weight) C: 0.1-1.0%, Mn: 10-25%, Si: up to 0.5%, Al: 0.3-2%, Cr: 1.5-3.5%, S: <0.03%, P: <0.08%, N: <0.1%, Mo: <2%, B: <0.01%, Ni: <8%, Cu: <5%, Ca: up to 0.015%, at least one element from the group “V, Nb” with the following proviso: Nb: 0.01-0.5%, V: 0.01-0.5% and optionally Ti: 0.01-0.5% and iron and unavoidable, production-related impurities as the remainder.

Abstract: The invention relates to a wheel rim for a motor vehicle which can be economically manufactured, with a wheel disc made of steel sheet and a rim flap running around the circumference of the wheel disc. Due to the fact that the steel sheet of the wheel disc is formed from at least three superimposed steel layers, joined to one another by roll-bonding in a non-detachable manner, of which the inner core layer has a lower strength than the outer layers, it is thereby guaranteed that the wheel rim according to the invention, with a low weight, can safely accommodate the forces arising in practical operation.

Abstract: The invention relates to a metal strip which is produced from steel by hot rolling and by cold rolling of the metal strip. The invention also relates to a blank produced from the metal strip, the use of the metal strip, and to a method of producing it. The object of providing metal strip from which components of minimum weight which are adapted to specific loads can be produced with little cost or complication is achieved by metal strip of the generic kind which, after the cold rolling, is of constant thickness and has, section by section, regions whose mechanical properties vary. What “after the cold rolling” means, for the purposes of the present invention, is that, immediately on completion of the cold rolling, i.e. without any further treatment such as heat treatment, regions whose mechanical properties vary are present in the metal strip.

Abstract: A multilayered composite part includes a plurality of steel alloy layers connected to one another, with at least one core layer consisting of a soft, well deformable steel alloy and at least one steel alloy layer of a very high strength steel alloy, arranged on the core layer. A multilayered composite part which is characterized simultaneously by a high strength paired with very good outer skin quality and very good paint adherence, is achieved in that at least one outer steel alloy layer of a soft, well deformable steel alloy is provided on the very high strength steel alloy layer.

Abstract: A composite material with a ballistic protective effect having a first, outer layer made of a first steel alloy and at least one second layer which is arranged under the first layer and is made of a second steel alloy. The composite material with a ballistic protective effect allows for a reduction in the weight or the wall thicknesses of the composite material in comparison to conventional composite ballistic materials, by utilizing a first steel alloy of the first layer that has the following alloy constituents in percent by weight (% by weight): 0.06%?C?1.05%, 0.05%?Si?1.65%, 0.3%?Mn?2.65%, 0.015%?Al?1.55%; Cr?1.2%, Ti?0.13%, Mo?0.7%, Nb?0.1%, B?0.005%, P?0.08%, S?0.01%, Ni?4.0%, and V?0.05%, the remainder being Fe and inevitable impurities. The second layer of the composite material having a higher elongation than the first layer.

Abstract: The invention relates to a wheel rim for a motor vehicle which can be economically manufactured, with a wheel disc made of steel sheet and a rim flap running around the circumference of the wheel disc. Due to the fact that the steel sheet of the wheel disc is formed from at least three superimposed steel layers, joined to one another by roll-bonding in a non-detachable manner, of which the inner core layer has a lower strength than the outer layers it is thereby guaranteed that the wheel rim according to the invention, with a low weight, can safely accommodate the forces arising in practical operation.

Abstract: A use of a coilable multi-layer metallic composite material produced by means of roll-cladding in a vehicle structure, in particular a body structure, provides an alternative to monolithic materials. The composite material used in a vehicle structure is a lightweight composite material and comprises three layers of a steel alloy, wherein at least one of the layers is formed from a high-strength or very high-strength steel alloy.

Abstract: A multilayered composite part includes a plurality of steel alloy layers connected to one another, with at least one core layer consisting of a soft, well deformable steel alloy and at least one steel alloy layer of a very high strength steel alloy, arranged on the core layer. A multilayered composite part which is characterized simultaneously by a high strength paired with very good outer skin quality and very good paint adherence, is achieved in that at least one outer steel alloy layer of a soft, well deformable steel alloy is provided on the very high strength steel alloy layer.

Abstract: A bipolar plate which can be produced particularly economically for a fuel cell, with which a high degree of efficiency is guaranteed over a long service life. The bipolar plate has a core layer consisting of a steel material, the surfaces of said core layer, which are associated with the respective electrolyte carriers of the fuel cell, having a corrosion protection layer, protecting the core layer against corrosion. The corrosion protection layers consist of a metal material and extend on both sides over the whole surface of the core layer. At the same time the corrosion protection layers are in turn coated over the whole surface with an electrically conductive functional coating, which is essentially entirely impermeable for the metal ions emerging from the core layer and/or the corrosion protection layers. The invention likewise relates to at least one fuel cell comprising a bipolar plate according to the invention.

Abstract: A method for producing cold-formable, high-strength steel strips or sheets with TWIP properties, wherein in successive working steps are carried out without interruption, uses a molten material of the following composition (mass %): C: 0.003-1.50%, Mn: 18.00-30.00%, Ni: ?10.00%, Si: ?8.00%, Al: ?10.00%, Cr: ?10.00%, N: ?0.60%, Cu: ?3.00%, P: ?0.40%, S: ?0.15%, selectively one or more components from the Se, Te, V, Ti, Nb, B, REM, Mo, W, Co, Ca and Mg group provided that the total content of Se, Te is ?0.25%, the total content of V, Ti, Nb, B, REM is ?4.00%, the total content of Mo, W, Co is ?1.50% and the total content of Ca, Mg is ?0.50%, the rest being iron and melting conditioned impurities, wherein the content of Sn, Sb, Zr, Ta and As, whose total content is equal to or less than 0.30% is included in said impurities.