Patent application number | Description | Published |
20080308191 | Process For Melt Dip Coating a Strip of High-Tensile Steel - A process for melt dip coating a strip of high-tensile steel with alloy constituents including zinc and/or aluminum includes the following steps. The strip is heated in a continuous furnace initially in a reductive atmosphere to a temperature of approximately 650° C., at which the alloy constituents diffuse to the surface in small amounts. The surface, consisting predominantly of pure iron, is converted into an iron oxide layer by a short heat treatment at a temperature of up to 750° C. in a reaction chamber which is integrated in a continuous furnace and has an oxidizing atmosphere. In a subsequent annealing treatment at a higher temperature in a reductive atmosphere, this iron oxide layer prevents the alloy constituents from diffusing to the surface. In the reductive atmosphere, the iron oxide layer is converted into a pure iron layer to which the zinc and/or aluminium are applied in the molten bath with optimum adhesion. | 12-18-2008 |
20090199931 | Method for Melt Immersion Coating of a Flat Steel Product Made of High Strength Steel - A method for coating a flat steel product manufactured from a high strength steel with a metallic coating, wherein the flat steel product is initially subjected to a heat treatment, in order then, in the heated state, to be hot-dip galvanized with the metallic coating in a melting bath containing overall at least 85% zinc and/or aluminum. The heat treatment includes heating the steel product in a reducing atmosphere, followed by converting a surface of the flat product to an iron oxide layer by a heat treatment lasting 1 to 10 secs in an oxidizing atmosphere, followed by annealing in a reducing atmosphere over a period of time which is longer than the duration of the formation of the iron oxide layer such that the iron oxide layer is reduced at least on its surface to pure iron, followed by cooling the product to a melting bath temperature. | 08-13-2009 |
20100024925 | Steel Sheet Product Provided with an Anticorrosion Coating and Process for Producing It - A flat steel product, and a method for its production, which is formed from a steel substrate, such as strip or sheet steel, and a zinc-based corrosion protection coating, applied to at least one side of the steel substrate, which contains (in wt. %) Mg: 0.25 to 2.5%, Al: 0.2 to 3.0%, Fe: ≦4.0%, and optionally in total up to 0.8% of one or more elements of the group Pb, Bi, Cd, Ti, B, Si, Cu, Ni, Co, Cr, Mn, Sn and rare earths, remainder zinc and unavoidable impurities are described. The corrosion protection coating has an Al content of maximum 0.5 wt. % in an intermediate layer extending between a surface layer directly adjacent to the surface of the flat steel product and a border layer adjacent to the steel substrate and with a thickness amounting to at least 20% of the total thickness of the corrosion protection coating. | 02-04-2010 |
20100294400 | METHOD FOR PRODUCING A STEEL COMPONENT BY HOT FORMING AND STEEL COMPONENT PRODUCED BY HOT FORMING - A method for producing a steel component provided with a metallic coating which protects against corrosion, comprising the following steps: | 11-25-2010 |
20110017362 | STEEL FLAT PRODUCT HAVING A METALLIC COATING WHICH PROTECTS AGAINST CORROSION AND METHOD FOR PRODUCING A METALLIC ZN-MG COATING, WHICH PROTECTS AGAINST CORROSION, ON A STEEL FLAT PRODUCT - A steel flat product having a Zn—Mg—Al coating. The coating, which in addition to zinc and unavoidable impurities, comprises in wt. %: Mg: 4-8%, Al: 0.5-1.8% and optionally one or more of the following: Si: <2%, Pb: <0.1%, Ti: <0.2%, Ni: <1%, Cu: <1%, Co: <0.3%, Mn: <0.5%, Cr: <0.2%, Sr: <0.5%, Fe: <3%, B: <0.1%, Bi: <0.1%, Cd: <0.1%, REM<0.2%, and Sn<0.5%. The steel flat product according to the invention is not only outstandingly protected against corrosion, but also welds well and coats well with an organic layer applied subsequently. The invention also relates to a method for producing a steel flat product having a Zn—Mg—Al coating. | 01-27-2011 |
20120085466 | Method For Producing A Steel Component By Hot Forming And Steel Component Produced By Hot Forming - A method for producing a steel component provided with a metallic coating which protects against corrosion, in which a steel flat product, produced from an alloyed heat-treated steel, is coated with an Al coating which contains ≧85% wt. Al and optionally ≦15% wt. Si, a Zn coating with ≧90% wt. Zn, and a top layer, the main constituent of which is at least one metal salt of phosphoric acid or diphosphoric acid and which additionally can contain contents of up to 45% of an Al:Zn ratio as well as optionally metal oxides, metal hydroxides and/or sulphur compounds, the steel flat product is heat treated at ≧750° C., and the steel component is hot-formed from the heated steel flat product. The hot-formed steel component is cooled at a cooling rate sufficient to form a tempered or martensitic structure. | 04-12-2012 |
20120125491 | Method for the Hot-Dip Coating of a Flat Steel Product Containing 2 - 35 wt.% of Mn, and a Flat Steel Product - A method by which a flat steel product containing 2-35 wt. % of Mn can be provided with a coating of Zn which adheres well by annealing at an annealing temperature T | 05-24-2012 |
20120164472 | Method of Producing a Steel Component Provided with a Metallic Coating Giving Protection Against Corrosion, and a Steel Component - A method by which a steel component can be produced, which is provided with a metallic coating which adheres well and which provides protection against corrosion, from a flat steel product produced from a steel material containing 0.3-3 wt.-% manganese and having a yield point of 150-1100 MPa and a tensile strength of 300-1200 MPa coated with an anti-corrosion coating which comprises a coating of ZnNi alloy which is electrolytically deposited on the flat steel product, which coating is composed in a single phase of γ-ZnNi phase and which contains, as well as zinc and unavoidable impurities, 7-15 wt.-% nickel. | 06-28-2012 |
20130180305 | Method for Producing a Flat Steel Product which can be Readily Formed, Flat Steel Product and Method for Producing a Component from such a Flat Steel Product - A readily formable flat steel product has a ductile edge layer that is from 10 to 200 μm thick and has a ductility greater than a ductility of an inner core layer of the flat steel product. The readily formable flat steel product is produced by annealing a flat steel product having a C content of from 0.1 to 0.4% by weight in a continuous furnace. The annealing is carried out under an annealing atmosphere that contains from 0.1 to 25% by vol. of H | 07-18-2013 |