Classifications

• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
  • C23C2/04—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor characterised by the coating material
  • C23C2/12—Aluminium or alloys based thereon
• • C—CHEMISTRY; METALLURGY
  • C21—METALLURGY OF IRON
  • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
  • C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
  • C21D9/46—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for sheet metals
• • C—CHEMISTRY; METALLURGY
  • C21—METALLURGY OF IRON
  • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
  • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
  • C21D1/18—Hardening; Quenching with or without subsequent tempering
• • C—CHEMISTRY; METALLURGY
  • C21—METALLURGY OF IRON
  • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
  • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
  • C21D1/34—Methods of heating
• • C—CHEMISTRY; METALLURGY
  • C21—METALLURGY OF IRON
  • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
  • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
  • C21D1/62—Quenching devices
  • C21D1/673—Quenching devices for die quenching
• • C—CHEMISTRY; METALLURGY
  • C21—METALLURGY OF IRON
  • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
  • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
  • C21D1/74—Methods of treatment in inert gas, controlled atmosphere, vacuum or pulverulent material
  • C21D1/76—Adjusting the composition of the atmosphere
• • C—CHEMISTRY; METALLURGY
  • C21—METALLURGY OF IRON
  • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
  • C21D7/00—Modifying the physical properties of iron or steel by deformation
  • C21D7/13—Modifying the physical properties of iron or steel by deformation by hot working
• • C—CHEMISTRY; METALLURGY
  • C21—METALLURGY OF IRON
  • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
  • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
  • C21D8/005—Modifying the physical properties by deformation combined with, or followed by, heat treatment of ferrous alloys
• • C—CHEMISTRY; METALLURGY
  • C21—METALLURGY OF IRON
  • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
  • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
  • C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
  • C21D8/0221—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
  • C21D8/0236—Cold rolling
• • C—CHEMISTRY; METALLURGY
  • C21—METALLURGY OF IRON
  • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
  • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
  • C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
  • C21D8/0278—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips involving a particular surface treatment
• • C—CHEMISTRY; METALLURGY
  • C21—METALLURGY OF IRON
  • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
  • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
  • C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
  • C21D8/04—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips to produce plates or strips for deep-drawing
  • C21D8/0421—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips to produce plates or strips for deep-drawing characterised by the working steps
  • C21D8/0436—Cold rolling
• • C—CHEMISTRY; METALLURGY
  • C21—METALLURGY OF IRON
  • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
  • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
  • C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
  • C21D8/04—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips to produce plates or strips for deep-drawing
  • C21D8/0478—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips to produce plates or strips for deep-drawing involving a particular surface treatment
• • C—CHEMISTRY; METALLURGY
  • C21—METALLURGY OF IRON
  • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
  • C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
  • C21D9/46—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for sheet metals
  • C21D9/48—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for sheet metals deep-drawing sheets
• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22C—ALLOYS
  • C22C21/00—Alloys based on aluminium
  • C22C21/02—Alloys based on aluminium with silicon as the next major constituent
• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22C—ALLOYS
  • C22C38/00—Ferrous alloys, e.g. steel alloys
  • C22C38/002—Ferrous alloys, e.g. steel alloys containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22C—ALLOYS
  • C22C38/00—Ferrous alloys, e.g. steel alloys
  • C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22C—ALLOYS
  • C22C38/00—Ferrous alloys, e.g. steel alloys
  • C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22C—ALLOYS
  • C22C38/00—Ferrous alloys, e.g. steel alloys
  • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
  • C22C38/22—Ferrous alloys, e.g. steel alloys containing chromium with molybdenum or tungsten
• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22C—ALLOYS
  • C22C38/00—Ferrous alloys, e.g. steel alloys
  • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
  • C22C38/26—Ferrous alloys, e.g. steel alloys containing chromium with niobium or tantalum
• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22C—ALLOYS
  • C22C38/00—Ferrous alloys, e.g. steel alloys
  • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
  • C22C38/28—Ferrous alloys, e.g. steel alloys containing chromium with titanium or zirconium
• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22C—ALLOYS
  • C22C38/00—Ferrous alloys, e.g. steel alloys
  • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
  • C22C38/32—Ferrous alloys, e.g. steel alloys containing chromium with boron
• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22C—ALLOYS
  • C22C38/00—Ferrous alloys, e.g. steel alloys
  • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
  • C22C38/38—Ferrous alloys, e.g. steel alloys containing chromium with more than 1.5% by weight of manganese
• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
  • C23C2/14—Removing excess of molten coatings; Controlling or regulating the coating thickness
  • C23C2/16—Removing excess of molten coatings; Controlling or regulating the coating thickness using fluids under pressure, e.g. air knives
  • C23C2/18—Removing excess of molten coatings from elongated material
  • C23C2/20—Strips; Plates
• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
  • C23C2/26—After-treatment
• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
  • C23C2/26—After-treatment
  • C23C2/28—Thermal after-treatment, e.g. treatment in oil bath
• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
  • C23C2/34—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor characterised by the shape of the material to be treated
  • C23C2/36—Elongated material
  • C23C2/40—Plates; Strips
• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C24/00—Coating starting from inorganic powder
  • C23C24/08—Coating starting from inorganic powder by application of heat or pressure and heat
• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C28/00—Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of groups C23C2/00 - C23C26/00 or by combinations of methods provided for in subclasses C23C and C25C or C25D
  • C23C28/30—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer
  • C23C28/32—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one pure metallic layer
  • C23C28/321—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one pure metallic layer with at least one metal alloy layer
• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C8/00—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
  • C23C8/06—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases
  • C23C8/08—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases only one element being applied
  • C23C8/10—Oxidising
• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C8/00—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
  • C23C8/06—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases
  • C23C8/08—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases only one element being applied
  • C23C8/10—Oxidising
  • C23C8/12—Oxidising using elemental oxygen or ozone
  • C23C8/14—Oxidising of ferrous surfaces

Definitions

• the invention relates to a method for producing a sheet metal component by hot forming a flat steel product, which is provided with an anti-corrosion coating in particular by hot-dip coating and which is given at least one section by flexible cold rolling, which has a different thickness than another section of the flat steel product adjoining it. the transition between the sections of the flat steel product having different thicknesses being abrupt.
• Fiber steel products are understood here to mean rolled products whose length and width are each significantly greater than their thickness. These include, in particular, steel strips and steel sheets.
• a process is known with which a component is formed from a hot-dip galvanized sheet steel intended for use at high temperatures of 450 - 650 °C with an aluminum-based anti-corrosion coating, which is said to have improved oxidation resistance at the high operating temperatures.
• the anti-corrosion coating of the sheet consists of up to 13% by weight Si, 0.5 - 8% by weight Mg and, if necessary, one or more metals from the group "0.001 - 1% by weight Sr, 0.001 - 1 wt% Ca, 0.0001 - 0.1 wt% Be, 0.001 - 1 wt% Ba".
• an alloy layer is formed between the steel substrate and the anti-corrosion coating of the flat steel product.
• the Mg present in the anti-corrosion coating causes Mg or Mg oxides to accumulate on the exposed surfaces of the coating in the area of cracks that develop in the anti-corrosion coating.
• up to 50% by volume of iron oxides can be found in a transitional layer between the anti-corrosion coating and the steel substrate.
• fully killed 22MnB5 steel available on the market contains, in addition to iron and unavoidable impurities, in % by weight, 0.10 - 0.250% C, 1.0 - 1.4% Mn, 0.35 - 0.4% Si, up to 0.03% P, up to 0.01% S, up to 0.040% Al, up to 0.15% Ti, up to 0.1% Nb, in total up to 0.5% Cr + Mo, and up to 0.005% B.
• the steel flat products are coated according to the known method with an anti-corrosion coating on Al -Base which contains effective amounts of 0.005 - 0.7% by weight of at least one alkaline earth metal or transition metal as an additional alloying component.
• Si contents of 3-15% by weight and Fe contents of up to 5% by weight can also be present in the coating.
• Mg in contents of 0.1-0.5% by weight is preferably used as the at least one alkaline earth metal or transition metal of the protective coating, with calcium, strontium, sodium or barium also being possible as a substitute or in addition.
• the Al-based protective coating can be applied to the steel substrate by hot-dip coating, also known as "hot-dip aluminizing" in technical jargon, or by a gas deposition process, e.g. the well-known PVD (Physical Vapor Deposition) or CVD (Chemical Vapor Deposition) process.
• hot-dip coating also known as "hot-dip aluminizing” in technical jargon
• gas deposition process e.g. the well-known PVD (Physical Vapor Deposition) or CVD (Chemical Vapor Deposition) process.
• “Flexible rolling” is a process for the production of metal strips with different strip thicknesses defined over their length.
• the height of the roll gap provided between two work rolls of a roll stand, through which the flat steel product to be rolled has to pass is usually varied during rolling. In this way, sections of greater thickness (wider roll gap) and less thickness (narrower roll gap) can be produced on the flat steel product in succession over the length of the flat steel product.
• flexible rolling is ideally suited for producing a flat steel product whose properties are adapted, for example, to the locally limited loads acting on it during use or to the requirements placed on its deformation behavior.
• flexible rolling can be used to form flat steel products in such a way that a component obtained from such a flat steel product by forming has different sheet thicknesses at the required locations, which enable the component to withstand high loads while having a minimized weight.
• the invention proposes that at least the method steps specified in claim 1 be completed during the flexible cold rolling of a flat steel product provided with an anti-corrosion coating.
• a flat steel product which comprises an MnB steel substrate composed in a specific way and an Al-based anti-corrosion coating applied thereto, in particular by hot-dip coating.
• hot-dip coating is carried out in a conventional manner for the purposes of the invention, the flat steel product is passed through a molten bath alloyed according to the invention and the coating layer thickness of the protective layer is adjusted from the flat steel product emerging from the molten bath by means of wiping nozzles. Air is used as the wiping medium.
• the oxide layer on the anti-corrosion layer is "frozen", i.e. it cannot form according to the chemical equilibrium rules.
• the anti-corrosion coating of the flat steel product contains at least one alkaline earth metal or transition metal or is wetted with a solution containing at least one such alkaline earth metal or transition metal in step b), which is carried out if necessary.
• the solution used for this purpose according to the invention is preferably an aqueous solution whose solvent “water” is easily mastered in terms of process technology and is harmless with regard to the environment.
• Step b) is carried out when the anti-corrosion coating contains too little of the at least one alkaline earth metal or transition metal.
• wetting with the aqueous solution containing the at least one alkaline earth metal or transition metal also take place as a supplementary measure if the anti-corrosion coating contains a fundamentally sufficient amount of alkaline earth metal or transition metal, but other amounts of the at least alkaline earth metal or transition metal are on the surface of the Anti-corrosion coating are to be applied in order to ensure the occurrence of the effect used according to the invention of the presence of these metals in or on the anti-corrosion layer.
• the alkaline earth metals and transition metals alloyed with the anti-corrosion coating and/or applied in the form of a solution to the surface of the anti-corrosion coating for the purposes of the invention include, in particular, magnesium (“Mg”) and calcium (“Ca”), but also beryllium (“Be”), strontium (“Sr”) and barium (“Ba”).
• the application of the solution containing the at least one alkaline earth metal or transition metal can take place before or after the flexible rolling. It is essential that before heating to the hot-forming temperature, there is a sufficient quantity of the respective alkaline earth metal or transition metal in or on the anti-corrosion coating.
• step c) the steel flat product provided and optionally coated with the layer containing at least one alkaline earth metal or transition metal is flexibly cold-rolled at room temperature in a conventional manner in order to give it sections of different thicknesses.
• the steel flat product is rolled with rolling degrees W, which are 0.1 to 80%.
• a degree of rolling W of 48.64% is required to produce a second section with a thickness X2 of 2.5 mm a rolling degree W of 10.00%, to produce a third section with a thickness X3 of 2.15 mm a rolling degree W of 27.90% and to produce a fourth section with a thickness X4 of 2.25 mm requires a degree of rolling W of 22.22%.
• Particularly practical rolling degrees W are 0.1 - 60%, in particular 0.1 - 50%.
• the degree of rolling W specifically set in each case depends on the desired extent of reduction in the thickness of the flat steel product compared to the initial state.
• the range specified here for the degree of rolling W thus only defines the limits within which the degree of rolling set in each case is set according to the invention.
• the thickness of the steel flat product is specifically reduced in limited length sections. Due to the constant volume, this reduction in thickness is inevitably accompanied by an elongation of the flat steel product.
• the aluminum alloy of the anti-corrosion coating on a flat steel product processed according to the invention is so ductile that it can follow the deformation of the flat steel product occurring in the longitudinal and thickness direction, even in the border areas where the sections of different thickness meet.
• the protective oxide layer on the anti-corrosion coating is much more brittle, with the result that it locally cracks due to the deformation of the steel flat product.
• the resulting cracks are quickly closed again by newly forming oxides. Since this process takes place in the ambient atmosphere and without separate temperature supply or removal, the new oxide layer can form in such a way that it corresponds to the chemical equilibrium at the location of the crack, taking into account the respective ambient conditions. Damage to the oxide layer originally present during flexible rolling is closed by new oxides formed in the course of cold rolling, so that the finished flexibly rolled flat steel product has a tightly closed oxide layer again. This is characterized by areas where the original oxide layer has remained and areas where a new oxide layer has been formed.
• the surface of a flat steel product that has been flexibly hot-rolled according to the invention is 80-90% covered with the original oxide layer formed before the flexible rolling, while the remaining surface is covered with the oxide layer formed in the course of the flexible rolling itself new oxide layer is covered.
• the ratio of the Si and Al content of the oxide layer and the ratio of the Al, Si and Mg content of the oxide layer also depend on the values set by flexible rolling Degree of rolling W.
• the original oxide layer present on the flat steel product processed according to the invention before flexible cold rolling typically consists of silicon, magnesium and aluminum oxides, the proportion of Si being significantly smaller than the proportion of Mg, which in turn is smaller than the proportion of Al.
• the oxide layer contains 10-40% C, 30-60% O, 4-30% Al, 0-5% Si and 1-20% of at least one alkaline earth metal or transition metal, in particular mg, before
• small amounts of Fe of up to 10 atom % can be present in the oxide layer. This applies in particular if the anti-corrosion coating has been applied by hot dip coating.
• the thickness of the original oxide layer is typically 5-600 nm, in particular 5-300 nm, particularly preferably 5-150 nm.
• the original oxide layer covers the surface of the anti-corrosion coating completely, ie 100%.
• the oxide layer newly formed by the flexible cold rolling which can form in equilibrium, also essentially consists of oxides of silicon, magnesium and aluminum.
• the quantity distribution of the Si, Mg and Al oxides corresponds to their distribution in the primary oxide layer.
• the secondary oxide layer typically consists of, in atom %, 10 - 40 % C, 40-60% O, 20-30% Al, 0-5% Si and 1-20% of at least one alkaline earth metal or transition metal, in particular Mg, with small traces of iron of up to 10 atoms also in the secondary oxide layer -% may be included.
• the thickness of the secondary oxide layer is 1-100 nm, in particular 1-80 nm or 1-50 nm, with thicknesses of up to 30 nm having turned out to be particularly favorable.
• the percentage area F ox of the secondary oxide layer in the total oxide layer covering the anti-corrosion coating of the steel flat product processed according to the invention after flexible cold rolling is related to the degree of rolling W, where F ox ⁇ W.
• compositions of the oxide layers can be determined using X-ray photoelectron spectroscopy (XPS).
• XPS X-ray photoelectron spectroscopy
• the sample of the steel flat product to be examined, for which the composition and thickness are to be determined is degreased with n-heptane, rinsed with propanol and blown off in air.
• the sample is then attached to a sample carrier, introduced into the measuring chamber of the X-ray photoelectron spectroscope and examined in a high vacuum.
• the boiler pressure is typically less than 5x10 8 mbar.
• Argon is typically used as the bombardment gas.
• the radiation was excited as Al K with a bombardment voltage of 2 or 4 kV. At least one measurement regarding the composition and oxide layer thickness is carried out on each sample.
• composition and thickness determined in this way of the oxide layer present on the circuit board examined is therefore also referred to as "average composition” or "average thickness”.
• the steel flat product is heated to a hot forming temperature, if necessary from that previously
• a hot forming temperature if necessary from that previously
• at least one is separated, which is then further processed according to the invention as a steel flat product.
• composition of the anti-corrosion coating selected according to the invention and/or the additional application of the alkaline earth metal or transition metal to the anti-corrosion coating by means of the aqueous solution ensures that a primary oxide layer formed from the at least one alkaline earth metal or transition metal is formed as a result of the heat treatment carried out before hot forming of the anti-corrosion coating.
• the invention is based on the finding that on a steel flat product that is provided with an aluminum-based (“Al-based”) anti-corrosion coating, which is doped with at least one alkaline earth metal or transition metal according to the invention, during the hot forming carried out heating on the anti-corrosion coating forms an oxide layer ("primary oxide layer"), which protects the underlying layers of the anti-corrosion coating and thus the steel substrate of the steel flat product against exposure to the ambient atmosphere.
• the primary oxide layer in question is formed in such a way that it is in chemical equilibrium under the conditions prevailing during heating, in particular those determined by the respective hot-forming temperature. This process also continues during and after hot forming. Injuries to the oxide layer present before heating and hot forming are closed very quickly.
• an oxide layer forms immediately as soon as the surface of the anti-corrosion layer is exposed to even the smallest amounts of oxygen.
• the oxide layer present on the anti-corrosion coating covers the underlying aluminum of the anti-corrosion coating, so that contact of the Al with the ambient moisture and the associated elimination of larger amounts of hydrogen during heating to the hot-forming temperature or the hot forming itself can be prevented.
• the penetration of relatively large amounts of hydrogen into the anti-corrosion coating and the steel substrate of a flat steel product processed according to the invention can thus be effectively suppressed.
• the effects used by the invention occur particularly reliably when the alkaline earth metal or transition metal additionally present in the anti-corrosion coating or additionally applied to the anti-corrosion coating is magnesium ("Mg"), i.e. when Mg alone or in combination with others elements belonging to the group of alkaline earth metals or transition metals are present in the levels provided according to the invention in the anti-corrosion coating provided according to the invention of a flat steel product processed according to the invention or is additionally applied by means of the aqueous solution if the alkaline earth metal or transition metal content in the anti-corrosion coating is too low.
• Mg magnesium
• the method according to the invention is suitable for processing flat steel products with a wide range of thicknesses.
• flat steel products can be processed with a thickness of 0.6-7 mm.
• the flat steel product provided in step a) can be produced in any manner known from the prior art.
• the method according to the invention is particularly suitable for processing flat steel products with a thickness of 0.8-4 mm, in particular 0.8-3 mm.
• flat steel products can also be provided in step a), which are formed from a stack of metal sheets comprising, for example, three to five metal layers, which have been connected in a manner known per se, for example by roll cladding, to form a uniform flat steel product.
• step a) for the method according to the invention in the manner of Taylored blanks from different sheet metal blanks welded to one another or similarly assembled flat steel products and steel strips, which are welded to one another and together form the flat steel product to be processed, can be provided for the process according to the invention.
• the respective flat steel product provided according to the invention consists of a steel which has a composition typical of MnB steels. Such steels typically have yield strengths of 250 - 580 MPa and tensile strengths of 400 - 720 MPa in the as-delivered condition.
• the steel substrate of which consists, in a manner known per se, of 0.07 - 0.4% by weight C, 1.0 - 2% by weight Mn, 0.06 - 0.4% by weight Si, up to 0 .03 wt% P, up to 0.01 wt% S, up to 0.1 wt% Al, up to 0.15 wt% Ti, up to 0.6 wt% Nb, up to 0.005% by weight B, up to 0.5% by weight Cr, up to 0.5% by weight Mo, the sum of the contents of Cr and Mo being at most 0.5% by weight is, the remainder consists of iron and unavoidable impurities.
• the prerequisite for the effects achieved according to the invention is the presence of at least one alkaline earth metal or transition metal in or on the Al-based anti-corrosion coating provided according to the invention.
• a sufficient amount of alkaline earth metal or transition metal can be alloyed with the anti-corrosion coating.
• the minimum required alkaline earth metal or transition metal content in the anti-corrosion coating is 0.1% by weight and can reach up to 5% by weight.
• Alkaline earth or transition metal contents of at least 0.11 wt permit. If the alkaline earth metal or transition metal content is more than 5% by weight, the Oxide layer and thus dust formation, which should be avoided.
• the alkaline earth metal or transition metal content of the anti-corrosion coating applied in step a) can be limited to a total of at most 1.5% by weight, in particular at most 0.6% by weight. If the alloy of the anti-corrosion coating present on the steel substrate of a flat steel product processed according to the invention contains alkaline earth metals or transition metals that are sufficiently effective for the purposes according to the invention, these amounts to 0.1-5% by weight, in particular 0.11- 1.5% by weight or, especially, 0.11-0.6% by weight.
• step b) The optional application of the solution containing the respective alkaline earth metal or transition metal (step b)) can take place directly after the application of the anti-corrosion layer inline by spraying and squeezing or by conventional coil coating.
• salt solutions with up to 200 g/l are used for this purpose.
• the alkaline earth or transition metals can be present as sulfates, phosphates and nitrates or in oxidic form as a dispersion of alkaline earth metal or transition metal oxide particles. Chlorides should not be used due to the potential for corrosive attack. Silicates can also find application. However, it should be noted here that these connections can impede further processing due to possible silicon connections. Fluorine compounds are not suitable because they can react to form hydrofluoric acid when heated to the hot forming temperature. Mixtures formed from compounds of the type discussed herein and/or different alkaline earth or transition metals can also be used.
• the solution applied according to the invention, if necessary, to the surface of the anti-corrosion layer can additionally a network former such as bismuth nitrate and/or a wetting agent such as a surfactant.
• drying A separate drying treatment ("baking") is not normally necessary.
• the drying of the solution applied if necessary takes place by utilizing the process heat.
• work step b) required according to the invention is to be carried out inline in a hot-dip coating system
• the aqueous solution containing the at least one alkaline earth metal or transition metal can be applied at one point after the flat steel product has emerged from the molten bath and the coating thicknesses have been adjusted , at which the treated flat steel product is still warm enough for the solvent in the solution to evaporate quickly after contact with the surface of the flat steel product, i.e. the applied layer dries quickly.
• the solution can also be applied in an additional process step on a conventional coil coating system.
• a separate drying treatment can be useful if you want to ensure that the solution is dry before further processing. This applies in particular when water is used as the solvent.
• either the flat steel product itself can be 100-250° C., in particular 100-180° C., warm when the at least one alkaline earth metal or transition metal-containing solution is applied, or it can be subjected to a drying treatment at these temperatures.
• Typical drying times are 0-300 s, in particular 10-60 s. Drying times of "0 s" are achieved when the steel flat product or its surroundings are so hot when the solution is applied that the respective solvent when it hits the The surface of the anti-corrosion layer evaporates spontaneously, ie without waiting.
• work step b) can also be carried out in the factory of the manufacturer of the flat steel product.
• the flat steel product coated according to the invention is completely dry when it enters the furnace. Otherwise, the humidity brought into the oven by the water could lead to an excessive increase in the humidity of the oven atmosphere and thus to an unwanted Increase the dew point, which in turn would entail the risk of increased hydrogen absorption during the hot forming process.
• the anti-corrosion coating of the flat steel product provided according to the invention can optionally contain silicon ("Si") in amounts of up to 15% by weight, in particular up to 11% by weight, in order to reduce the formation of an iron-aluminum phase.
• Si contents of at least 3 wt. 11% by weight, specifically 8.5-11% by weight allow the positive influences of Si to be used particularly reliably in practice. With Si contents of at least 3% by weight, it is ensured that the alloy layer between the steel substrate and the anti-corrosion layer of a steel flat product according to the invention does not become too thick and optimal further processing properties are retained.
• Fe can be present in the anti-corrosion coating provided on a flat steel product provided according to the invention in contents of up to 5% by weight, in particular up to 4% by weight, especially up to 3.5% by weight.
• the Fe content is mainly due to the diffusion of Fe from the steel substrate and contributes to the optimal adhesion of the protective layer to the substrate.
• Fe contents of at least 1 wt. 5% by weight the positive influences of the presence of Fe can be used particularly reliably in practice.
• the anti-corrosion coating can be applied to the steel substrate of a flat steel product according to the invention in any known manner.
• Hot-dip coating also known as "hot-dip aluminizing”
• the respective flat steel product is a suitably heated molten bath composed in accordance with the provisions of the invention with regard to the composition of the anti-corrosion coating is passed.
• Such a hot-dip coating is particularly suitable for strip-shaped flat steel products with a thickness of up to 3 mm.
• one of the vapor deposition processes (PVD, CVD) already mentioned at the beginning can also have been used in order to apply the anti-corrosion coating.
• the application weight of an anti-corrosion coating present on a flat steel product processed according to the invention is typically 30-100 g/m 2 , in particular 40-80 g/m 2 , per side of the flat steel product.
• Mg in particular has proven to be suitable for the purposes according to the invention.
• Mg can be present alone or in combination with other alkaline earth metals or transition metals, such as the elements beryllium, calcium, strontium and/or barium already mentioned, in the coating applied according to the invention in order to use the effects aimed at according to the invention.
• the heating can be carried out in any suitable way. If a conventional continuous furnace is used for this purpose, in which the steel flat product or the blank is heated by radiant heat, the suitable holding time is typically 100-900 s, in particular 100-600 s or, particularly practical, 180-600 s If a hot forming temperature of 850 - 930 °C is selected, holding times of 180 - 600 s are usually sufficient in practice.
• a pre-alloying of the anti-corrosion layer can be carried out before hot forming in combination with heating to the hot forming temperature or as a separate treatment step.
• the flat steel product can be kept at temperatures of 650-1100° C. for a period of 10-240 s, in particular 30-90 s.
• the flat steel product heated in the manner according to the invention is fed within a transfer time customary in practice to a hot-forming device in which the flat steel product is hot-formed into the component (step e)).
• Steel sheets each had a thickness D and were provided with an Al-based anti-corrosion coating in a conventional manner by hot-dip coating.
• Five variants Z1 - Z5 of such an anti-corrosion coating were used, the compositions of which are given in Table 2.
• Each of the anti-corrosion coatings Z1-Z5 contained the Mg content shown in Table 2 as the alkaline earth metal or transition metal added in accordance with the provisions of the invention.
• the steel sheets AF each provided with one of the anti-corrosion coatings Z1-Z5, have been flexibly cold-rolled in a conventional manner, with a rolling degree W being achieved in each case via this cold-rolling.
• the steel sheets A - F, each provided with one of the anti-corrosion coatings Z1 - Z5, were heated in a conventional continuous furnace to a hot forming temperature of 850 - 930 °C in each case, with the holding time at the respective hot forming temperature being varied so that a sufficient amount of energy EE has been introduced into the respective sheet.
• the heating was carried out in two stages in order to first bring about a pre-alloying of the anti-corrosion coating. All other tests V1 - V3, V5 and V7 - V9 were heated in one stage.
• the sheet metal samples AF heated in this way to the respective hot forming temperature have been hot formed in a conventional manner in a tool provided for this purpose to form a sheet metal component.
• the steel sheets obtained were cooled to room temperature at a cooling rate of 20-1000 K/s.
• Table 3 shows the steel of the steel substrate of the steel sheet used in the tests V1 - V9, the respective coating applied to the steel sheet in question, the thickness D of the sheet metal samples examined, the coating weight of the coating before heating on the Hot forming temperature, the amount of heat introduced during heating to the hot forming temperature and the degree of rolling W achieved via flexible cold rolling are given.
• the percentage of area %OB of the newly formed oxide layer OB which was formed in the course of flexible cold rolling on the anti-corrosion coating of the steel sheet processed in each case, is determined by means of XPS analysis on the oxide layer densely covering the surface of the steel sheet overall been.
• the thicknesses D_OA of the original oxide layers OA present before the flexible rolling, the thicknesses D_OB of the oxide layers OB newly formed via the flexible rolling and present after the flexible rolling, and the thickness D_OP present after the hot forming are the same as the XPS measurement during heating the oxide layer formed on the hot-forming temperature and present on the component obtained after hot-forming has been determined.
• the relevant measurement results are summarized in Table 4.
• compositions of the oxide layer present on the anti-corrosion coating before flexible rolling, between flexible rolling and heating to the hot forming temperature and after hot forming were also determined on samples A - F using XPS measurements.
• Table 1 stolen C si Mn P S Al Nb Ti B A 0.08 0.33 0.95 0.025 0.020 0.013 0.09 0.010 0.005 B 0.23 0.38 1.3 0.020 0.007 0.013 - 0.03 0.004 C 0.38 0.37 1.38 0.020 0.008 0.013 - 0.10 0.005 D 0.20 0.35 1.35 0.020 0.008 0.012 - 0.02 0.004 E 0.14 0.25 1.07 0.010 0.001 0.08 0.025 0.010 0.002 f 0.24 0.30 1.3 0.022 0.008 0.012 - 0.02 0.004 Data in % by weight, remainder Fe and unavoidable impurities Anti-corrosion coating before hot forming mg si feet Z1 0.3 9.5 3 Z2 0.5 8th 3.5 Z3 0.1 10 3 Z4 2 8th 2.0 Z5 0.8 8th 3 Data in % by weight, remainder Al and unavoidable impurities attempt stolen Thick D anti-corrosion coating Print run weight per page rolling grade W A

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• 2020
  • 2020-09-02 EP EP20194103.6A patent/EP3964602A1/fr active Pending
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  • 2021-08-27 US US18/024,126 patent/US20230366056A1/en active Pending
  • 2021-08-27 CN CN202180067892.5A patent/CN116249793A/zh active Pending
  • 2021-08-27 WO PCT/EP2021/073759 patent/WO2022049003A1/fr active Application Filing

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