Abstract: The invention relates to a method for producing a component from a medium manganese flat steel product having 4 to less than 10 wt. % Mn, 0.0005 to 0.9 wt. % C, 0.02 to 10 wt. % Al, the remainder iron, including unavoidable steel-accompanying elements, and having a TRIP effect at room temperature. In order to produce a component, which is distinguished by very high strengths and an increased residual strain and re-shaping capacity, the flat steel product, according to the invention, is re-shaped by at least one re-shaping step to form a component and, before and/or during and/or after the at least one re-shaping step, the flat steel product is cooled down to a temperature of the flat steel product of less than room temperature to ?196° C. The invention further relates to a component produced by this method and to a use for said components.

Abstract: A cold-rolled or hot-rolled steel strip having a metal coating, the steel strip having iron as the main constituent and, in addition to carbon, an Mn content of 4.1 to 8.0 wt. % and optionally one or more of the alloy elements Al, Si, Cr, B, Ti, V, Nb and/or Mo. The surface of the uncoated steel strip is cleaned, a layer of pure iron is applied to the cleaned surface, an oxygen-containing iron-based layer is applied to the layer of pure iron and contains more than five mass percent oxygen. The steel strip is then annealed and, to attain a surface consisting substantially of metallic iron, is subjected to a reduction treatment in a reducing furnace while being annealed. The steel strip is then coated with the metallic coating by hot dipping. Uniform and reproducible adhesion conditions are hereby achieved for the metallic coating on the steel strip surface.

Abstract: A steel product includes the following chemical composition in wt. %: C: 0.01 to <0.3, Mn: 4 to <10, Al: 0.003 to 2.9, Mo: 0.01 to 0.8, Si: 0.02 to 0.8, Ni: 0.005 to 3, P: <0.04, S: <0.02, N: <0.02, with the remainder being iron including unavoidable steel-associated elements, wherein an alloy composition satisfies the equation 6<1.5 Mn+Ni<8; or the equation 0.11<C+Al<3, or an alloy composition contains, in addition to Ni, at least one or more of the elements, in wt. %, B: 0.0005 to 0.014; V: 0.006 to 0.1; Nb: 0.003 to 0.1; Co: 0.003 to 3; W: 0.03 to 2 or Zr: 0.03 to 1. The steel product has a microstructure of 2 to 90 vol. % austenite, less than 40 vol. % ferrite and/or bainite, with the remainder being martensite.

Abstract: A cold- or hot-rolled steel strip with a metallic coating, the steel strip having iron as the main constituent and, in addition to carbon, an Mn content of 8.1 to 25.0 wt. % and optionally one or more of the alloying elements Al, Si, Cr, B, Ti, V, Nb and/or Mo. The uncoated steel strip is first cleaned, a layer of pure iron is applied to the cleaned surface, an oxygen-containing, iron-based layer containing more than five mass percent of oxygen is applied to the layer of pure iron. The steel strip is then annealed and is reduction-treated in a reducing furnace atmosphere during the annealing treatment to obtain a surface consisting mainly of metallic iron. The steel strip is then hot-dip coated with the metallic coating. This creates uniform and reproducible bonding conditions for the coating on the steel strip surface.

Abstract: The invention relates to a method for producing a flat steel product made of a medium manganese steel having a TRIP/TWIP effect. The aim of the invention is to achieve an improvement in the yield strength when a sufficient residual deformability of the produced flat steel product is obtained. This aim is achieved by the following steps: cold rolling a hot or cold strip, annealing the cold-rolled hot or cold strip at 500 to 840° C. for 1 minute to 24 hours, temper rolling or finishing the annealed hot or cold strip to form a flat steel product having a degree of deformability between 0.3% and 60%. The invention further relates to a flat steel product produced according to said method and to a use thereof.

Abstract: The invention relates to a method for producing a component from a medium-manganese flat steel product with 4 to 12 wt % Mn, preferably more than 5 to less than 10 wt % Mn, and with TRIP/TWIP effect. In order to improve the degrees of deformation of the shaped component while at the same time reducing the forming forces, the invention proposes shaping the flat steel product into a component in a first shaping step at a temperature of the flat steel product of 60° C. to below Ac3, preferably from 60° C. to 450° C. The invention also relates to a component produced according to said method and to a use for said components.

Abstract: In a method for producing a flat steel product made of high-strength manganese steel, a hot or cold strip is provided with an alloy composition containing (in wt %): C: 0.0005 to 0.9; Mn: 4 to 12; Al: up to 10; P: <0.1; S: <0.1; N: <0.1; the remainder being iron, including unavoidable steel-alloying elements, with optional addition of one or more of the following elements (in wt %): Si: up to 6; Cr: up to 6; Nb: up to 1; V: up to 1.5; Ti: up to 1.5; Mo: up to 3; Sn: up to 0.5; Cu: up to 3; W: up to 5; Co: up to 8; Zr: up to 0.5; Ta: up to 0.5; Te: up to 0.5, B: up to 0.15. The hot or cold strip is flexibly rolled to a final thickness at a temperature of 60° C. to below Ac3 prior to a first rolling step.

Abstract: In a method for improving the weldability of high-manganese-containing steel strips which contain (in % by weight) from 6 to 30% of manganese, up to 1% of carbon, up to 15% of aluminum, up to 6% of silicon, up to 6.5% of chromium, up to 4% of copper and also total additions of titanium and zirconium of up to 0.7% and total additions of niobium and vanadium of up to 0.5%, balance iron including unavoidable steel-accompanying elements the steel strips are coated with a zinc-containing corrosion protection layer.

Abstract: A steel product includes the following chemical composition in wt. %: C: 0.01 to <0.3, Mn: 4 to <10, Al: 0.003 to 2.9, Mo: 0.01 to 0.8, Si: 0.02 to 0.8, Ni: 0.005 to 3, P: <0.04, S: <0.02, N: <0.02, with the remainder being iron including unavoidable steel-associated elements, wherein an alloy composition satisfies the equation 6<1.5 Mn+Ni<8; or the equation 0.11<C+Al<3, or an alloy composition contains, in addition to Ni, at least one or more of the elements, in wt. %, B: 0.0005 to 0.014; V: 0.006 to 0.1; Nb: 0.003 to 0.1; Co: 0.003 to 3; W: 0.03 to 2 or Zr: 0.03 to 1. The steel product has a microstructure of 2 to 90 vol. % austenite, less than 40 vol. % ferrite and/or bainite, with the remainder being martensite.

Abstract: The invention relates to a method for producing a component from a medium manganese flat steel product having 4 to less than 10 wt. % Mn, 0.0005 to 0.9 wt. % C, 0.02 to 10 wt. % Al, the remainder iron, including unavoidable steel-accompanying elements, and having a TRIP effect at room temperature. In order to produce a component, which is distinguished by very high strengths and an increased residual strain and re-shaping capacity, the flat steel product, according to the invention, is re-shaped by at least one re-shaping step to form a component and, before and/or during and/or after the at least one re-shaping step, the flat steel product is cooled down to a temperature of the flat steel product of less than room temperature to ?196° C. The invention further relates to a component produced by this method and to a use for said components.

Abstract: The invention relates to a method for producing a flat steel product made of a medium manganese steel having a TRIP/TWIP effect. The aim of the invention is to achieve an improvement in the yield strength when a sufficient residual deformability of the produced flat steel product is obtained. This aim is achieved by the following steps: cold rolling a hot or cold strip, annealing the cold-rolled hot or cold strip at 500 to 840° C. for 1 minute to 24 hours, temper rolling or finishing the annealed hot or cold strip to form a flat steel product having a degree of deformability between 0.3% and 60%. The invention further relates to a flat steel product produced according to said method and to a use thereof.

Abstract: The invention relates to a method for producing a component from a medium-manganese flat steel product with 4 to 12 wt % Mn, preferably more than 5 to less than 10 wt % Mn, and with TRIP/TWIP effect. In order to improve the degrees of deformation of the shaped component while at the same time reducing the forming forces, the invention proposes shaping the flat steel product into a component in a first shaping step at a temperature of the flat steel product of 60° C. to below Ac3, preferably from 60° C. to 450° C. The invention also relates to a component produced according to said method and to a use for said components.

Abstract: The invention relates to a method for producing a component by hot-forming a pre-product composed of steel, wherein the pre-product is heated to a temperature above 60° C. and below the Ac3 transformation temperature and then formed in this temperature range, wherein the component has a minimum tensile strength of 700 MPa and high elongation at break, wherein the pre-product has the following alloy composition in percent by weight: C: 0.0005 to 0.9; Mn: more than 3.0 to 12; the remainder iron including unavoidable steel-accompanying elements, with the optional addition of one or more of the following elements (in percent by weight): Al: up to 10; Si: up to 6; Cr: up to 6; Nb: up to 1.5; V; up to 1.5; Ti: up to 1.5; Mo: up to 3; Cu: up to 3; Sn: up to 0.5; W up to 5; Co: up to 8; Zr: up to 0.5; Ta: up to 0.5; Te: up to 0.5; B: up to 0.15; P: at most 0.1, in particular <0.04; S: at most 0.1, in particular <0.02; N: at most 0.1, in particular <0.05; Ca: up to 0.1.

Abstract: A composite pipe includes a carrier pipe and at least one protective pipe. The carrier pipe is produced from a non-corrosion resistant steel, which has at least a partially austenitic structure, with the following chemical composition (in wt. %): C: 0.005 to 1.4; Mn: 5 to 35; the remainder being iron including unavoidable elements accompanying steel, with the optional alloying of the following elements (in wt. %): Ni: 0 to 6; Cr: 0 to 9; Al: 0 to 15; Si: 0 to 8; Mo: 0 to 3; Cu: 0 to 4; V: 0 to 2; Nb: 0 to 2; Ti: 0 to 2; Sb: 0 to 0.5; B: 0 to 0.5; Co: 0 to 5; W: 0 to 3; Zr: 0 to 4; Ca: 0 to 0.1; P: to 0.6; S: 0 to 0.2; N: 0.002 to 0.3. In a method for producing a composite pipe of this type, the carrier pipe and the at least one protective pipe are mechanically or metallurgically connected to one another.

Abstract: In a method for improving the weldability of high-manganese-containing steel strips which contain (in % by weight) from 6 to 30% of manganese, up to 1% of carbon, up to 15% of aluminum, up to 6% of silicon, up to 6.5% of chromium, up to 4% of copper and also total additions of titanium and zirconium of up to 0.7% and total additions of niobium and vanadium of up to 0.5%, balance iron including unavoidable steel-accompanying elements the steel strips are coated with a zinc-containing corrosion protection layer.