WO2019124997A1 - Tôle d'acier galvanisée par immersion à chaud, à résistance élevée, possédant une excellente propriété de revêtement, et son procédé de fabrication - Google Patents

Tôle d'acier galvanisée par immersion à chaud, à résistance élevée, possédant une excellente propriété de revêtement, et son procédé de fabrication Download PDF

Info

Publication number
WO2019124997A1
WO2019124997A1 PCT/KR2018/016300 KR2018016300W WO2019124997A1 WO 2019124997 A1 WO2019124997 A1 WO 2019124997A1 KR 2018016300 W KR2018016300 W KR 2018016300W WO 2019124997 A1 WO2019124997 A1 WO 2019124997A1
Authority
WO
WIPO (PCT)
Prior art keywords
steel sheet
hot
dip galvanized
galvanized steel
oxide
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/KR2018/016300
Other languages
English (en)
Korean (ko)
Inventor
이원휘
김명수
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Posco Holdings Inc
Original Assignee
Posco Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Posco Co Ltd filed Critical Posco Co Ltd
Publication of WO2019124997A1 publication Critical patent/WO2019124997A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Images

Classifications

    • 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 of ferrous metals or ferrous alloys by deformation combined with, or followed by, heat treatment
    • C21D8/02—Modifying the physical properties of ferrous metals or ferrous alloys by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
    • 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 of ferrous metals or ferrous alloys by deformation combined with, or followed by, heat treatment
    • C21D8/02—Modifying the physical properties of ferrous metals or ferrous alloys by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
    • C21D8/0221—Modifying the physical properties of ferrous metals or ferrous alloys by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
    • C21D8/0226—Hot 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
    • 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
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C18/00—Alloys based on zinc
    • C22C18/04—Alloys based on zinc with aluminium 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
    • C22C38/02—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
    • C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
    • 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
    • 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
    • C23C2/02—Pretreatment of the material to be coated, e.g. for coating on selected surface areas
    • 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
    • C23C2/02—Pretreatment of the material to be coated, e.g. for coating on selected surface areas
    • C23C2/022—Pretreatment of the material to be coated, e.g. for coating on selected surface areas by heating
    • 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
    • C23C2/02—Pretreatment of the material to be coated, e.g. for coating on selected surface areas
    • C23C2/022—Pretreatment of the material to be coated, e.g. for coating on selected surface areas by heating
    • C23C2/0222—Pretreatment of the material to be coated, e.g. for coating on selected surface areas by heating in a reactive atmosphere, e.g. oxidising or reducing atmosphere
    • 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
    • C23C2/02—Pretreatment of the material to be coated, e.g. for coating on selected surface areas
    • C23C2/022—Pretreatment of the material to be coated, e.g. for coating on selected surface areas by heating
    • C23C2/0224—Two or more thermal pretreatments
    • 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
    • C23C2/02—Pretreatment of the material to be coated, e.g. for coating on selected surface areas
    • C23C2/024—Pretreatment of the material to be coated, e.g. for coating on selected surface areas by cleaning or etching
    • 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
    • C23C2/06—Zinc or cadmium or alloys based thereon
    • 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
    • C23C2/29—Cooling or quenching
    • 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

Definitions

  • the present invention relates to a high-strength hot-dip galvanized steel sheet excellent in plating ability and a method of manufacturing the same.
  • hot-dip galvanized steel is used to extend the life of automobiles, thereby improving corrosion resistance.
  • the surface of the steel sheet is plated with a certain amount of metal such as zinc, zinc having a higher oxidation tendency than iron is firstly corroded in the corrosive environment to protect the iron, which is called a sacrificial method.
  • the galvanizing is determined by the quality of the surface of the annealed steel sheet immediately before plating, and the quality of the surface is determined by annealing with elements having high oxidation tendency such as Mn, Si, and Al added to secure the physical properties of the high- The plating ability is deteriorated.
  • Korean Patent Publication No. 2010-0030627 discloses a method of oxidizing a steel sheet in a direct flame furnace in an oxidizing atmosphere by controlling the air-fuel ratio of air and fuel to 0.80 to 0.95 in an annealing process, , Mn or Al alone or a composite oxide is formed on the surface of the steel sheet, and then the iron oxide is reduced and annealed in a reducing atmosphere, followed by hot-dip galvanizing to provide a hot-dip galvanized or alloyed hot-dip galvanized steel sheet.
  • the components having high affinity with oxygen such as Si, Mn, and Al at a predetermined depth from the surface layer of the steel sheet are internally oxidized to inhibit diffusion to the surface layer.
  • the single or complex oxides can be reduced, and the wettability with zinc can be improved, which can reduce the plating. That is, when heated under a high oxygen partial pressure that can oxidize iron, the iron is oxidized up to a certain depth of the surface layer to form an iron oxide layer. Elements that are easier to oxidize than iron are no longer diffusing to the surface because they are oxidized and present as oxides under the iron oxide layer.
  • the iron oxide is easily reduced to iron in an atmosphere containing a certain amount of hydrogen and is present as a reduced iron layer in the surface layer, and an element or an oxide thereof which interferes with plating is present under the iron layer and is in contact with zinc Since it is not good, it has good wettability with zinc, and the plating ability is improved.
  • Si-doped steel Si is concentrated under the iron oxide immediately during the reduction process to form strip-shaped Si oxides, and peeling at the surface layer including the plating layer, namely, at the interface between the reduced iron and the underlying iron There is a problem that it is difficult to secure the adhesion of the plating layer.
  • Korean Patent Laid-Open Publication No. 2009-0006881 A discloses a method for manufacturing a steel ingot by oxidizing an alloy component such as Mn, Si, Al, etc. which is easily oxidized by maintaining a high dew point in the annealing furnace, A method is disclosed in which the oxides externally oxidized on the surface of the steel sheet after annealing are reduced to improve the plating ability.
  • This method can solve the plating problem due to the external oxidation of Si, which is easily oxidized by internal oxidation, but the effect is insufficient when a large amount of Mn which is relatively difficult to oxidize is added.
  • a high-strength hot-dip galvanized steel sheet in which no plating phenomenon occurs and a problem that the surface oxide is excessively concentrated and the plating layer peels off, and a method of manufacturing the same.
  • a high strength hot-dip galvanized steel sheet comprises a base steel sheet; A hot dip galvanized layer formed on the base steel sheet; And oxides of at least one element selected from Si, Mn and Al formed on the surface of the base steel sheet and / or the surface of the base steel sheet in an island shape at a depth of 5 mu m or less.
  • a method of manufacturing a high strength hot-dip galvanized steel sheet comprising: preparing a steel sheet; Applying iron oxide to the prepared ground steel sheet; Annealing the iron oxide coated steel sheet; And hot dip galvanizing the annealed ground steel sheet.
  • the oxide of the elements which interfere with the plating is dispersed and distributed on the surface of the base steel sheet, the problem that the base steel sheet and the hot-dip galvanized layer are not in contact with each other over a large area can be prevented, A hot-dip galvanized steel sheet excellent in adhesion of plating can be provided.
  • FIG. 1 is a conceptual diagram comparing the principle (a) in which peeling occurs in a conventional hot-dip galvanized steel sheet and the principle (b) of preventing the peeling of a hot-dip galvanized steel sheet in the present invention.
  • FIG. 2 is a process flow chart comparing the principle (a) in which peeling occurs in a conventional hot-dip galvanized steel sheet and the principle (b) of preventing the peeling of a hot-dip galvanized steel sheet in the present invention.
  • the content of each element in the present invention is based on weight unless otherwise specified. Also, the content of gas is based on volume unless otherwise specified.
  • the size or diameter of the oxide or the like adhered to the steel sheet means that the wide surface of the steel sheet is observed when the steel sheet is viewed from above, unless otherwise specified or otherwise.
  • the hot-dip galvanized steel sheet is not excluded from the scope of the hot-dip galvanized steel sheet of the present invention if it is formed of a zinc-based hot-dip galvanized sheet.
  • the hot-dip galvanized steel sheet of the present invention may also include a galvannealed (GA) steel sheet.
  • GA galvannealed galvanized
  • the inventors of the present invention have found out that the oxide layer of Si, Mn or Al (hereinafter simply referred to as "plating interfering element") is widely formed in the film form at the interface between the base steel sheet and the plated layer, And that the bonding of the plated layer is not smooth.
  • the plating layer is not fixed to the base steel sheet, and the plating layer is peeled off in a plate shape. Therefore, in the present invention, the oxide of the plating obstructing element is prevented from being formed in a large area, thereby improving the adhesion between the plating layer and the base steel sheet. That is, when the oxide of the interfering elements is formed on the island, even though the adhesion of the plating layer is poor at the position where the oxide on the island is present, the area is not wide and the adhesion strength of the surrounding plating layer is greatly affected The plating layer can be stably fixed to the steel sheet.
  • an oxide of interfering elements such as Si, Mn or Al is formed on the island between the base steel sheet and the plating layer.
  • the term " island phase " means that the circle-equivalent diameter is 5 mu m or less. The smaller the size of the island-shaped oxide is, the better the adhesion between the steel sheet and the plating layer is improved. Therefore, the lower limit of the size is not particularly limited. However, in one embodiment of the present invention, the lower limit of the size of the island- .
  • the formation of an island-shaped oxide between the base steel sheet and the plating layer is considered to include the concept that some of the oxides penetrate even below the surface of the base steel sheet.
  • the oxide may be present within a depth of 5 ⁇ m or less from the surface of the base steel sheet.
  • the oxide may be present on the surface of the steel sheet as described above.
  • the oxides are formed in an island phase, if the intervals are too narrow, they will have a behavior substantially similar to that of one large area oxide, so that the average interval of the island-shaped oxides may be 0.1 ⁇ or more. However, if the average distance between the oxides is increased, the oxides may be integrated in one place to form a large area oxide. Therefore, according to one embodiment of the present invention, the average distance of the oxides can be set to 5 ⁇ or less.
  • the mean spacing of the oxides may mean averaging the distance from the nearest oxide to each oxide (hereinafter the same meaning is used).
  • the oxides on the island may be an oxide of one element selected from Si, Mn and Al, a complex oxide of two or more of these elements, or a cluster of oxides of the respective elements.
  • the term 'complex oxide' means that two or more elements react with oxygen to form one oxide, and the oxide complex means that each individual oxide is simply aggregated.
  • Composites also include complexes of complex oxides.
  • iron oxide or iron (Fe) particles or a complex thereof may exist between the oxide on the island and the plating layer.
  • the iron oxide serves as a site for forming the plating obstruction elements so as to form an island phase.
  • iron particles formed by reducing iron oxide or iron oxide or a complex of iron oxide and iron particles are formed do.
  • the iron particles do not necessarily need to be reduced from the iron oxide, and may be included in the form of iron particles from the beginning.
  • the iron oxide, the iron particles, or the complex thereof may have a size of about 50 nm to 5 ⁇ .
  • the size means the circle equivalent diameter.
  • the base steel sheet of the present invention is not limited as long as it is a high strength base steel sheet containing a large amount of Si, Mn and Al.
  • the high strength in the present invention does not necessarily have to have high strength at the time of hot dip galvanizing, and it is enough to have a high strength by the subsequent heat treatment or the like.
  • the base steel sheet of the present invention may contain Si, Mn and Al as a total of at least 3.5% by weight, and in one embodiment Si: not less than 0.5%, Mn: not less than 2.0%, Sol. And Al: 1.0% or more.
  • Si not less than 0.5%
  • Mn not less than 2.0%
  • Al 1.0% or more.
  • the base steel sheet of the present invention comprises 0.05 to 0.3% of C, 0.1 to 2.0% of Si, Al: 0.005 to 1.5%, Mn: 1.5 to 8.0%, P: not more than 0.04% (excluding 0%), S: not more than 0.015% (excluding 0%), N: not more than 0.02% Cr: not more than 1.5% (including 0%), Mo: not more than 0.2% (including 0%), Ti: not more than 0.1% (including 0%), Sb: not more than 0.05% 0%), and B: 0.005% or less (including 0%).
  • the composition of the steel sheet is not limited thereto.
  • Carbon (C) is an important element added for the stabilization of the retained austenite.
  • it is preferably added in an amount of 0.05% or more.
  • the C content may be controlled to 0.05% or more. However, if the content exceeds 0.3%, there is a problem that the weldability is poor, which is not preferable.
  • Si contributes to stabilization of retained austenite as an element which suppresses precipitation of carbide in ferrite and promotes diffusion of carbon in ferrite into austenite.
  • Si can be added in an amount of 0.1% or more, but when the rolling property is considered, the upper limit of the content can be limited to 2.0%. Further, when the Si content is limited to 2.0% or less, the Si oxide can be prevented from being formed on the steel surface.
  • Aluminum (Al) is an element contributing to stabilization of retained austenite through inhibition of formation of carbide in ferrite, and may be added in an amount of 0.005% or more. However, if the content exceeds 1.5%, it is difficult to produce a sound slab through reaction with the mold flux during casting, and the surface oxidation can be formed to inhibit the molten conversion, so that the Al content is limited to 1.5% or less .
  • Manganese (Mn) is an indispensable element in the metamorphic steel for the formation and stabilization of retained austenite and for suppressing ferrite transformation during cooling.
  • Mn may be contained in an amount of 1.5% or more.
  • the Mn content may be limited to 8.0% or less because there is a problem that the band formation due to segregation caused by the slab and hot rolling process is excessive and hinders the physical properties.
  • S is an impurity element in the steel, and is an element that hinders ductility and weldability of a steel sheet.
  • the content exceeds 0.015%, the possibility of hindering the ductility and weldability of the steel sheet increases, so that the upper limit is limited to 0.015%.
  • Nitrogen (N) is a component effective to stabilize austenite.
  • the content exceeds 0.02%, there is a great risk of occurrence of brittleness and excessively precipitates AlN by bonding with Al, As shown in Fig.
  • the content of chromium (Cr) is preferably 1.5% or less (including 0%).
  • Cr is an element for increasing the hardenability and serves as an element for suppressing the formation of ferrite, and thus helps to secure 5 to 20% retained austenite, so that a small amount of Cr can be added as needed. However, if it exceeds 1.5%, the amount of iron alloy input will be excessive, which may cause cost increase. In one embodiment of the present invention, the Cr may be limited to 0.7% or less.
  • Molybdenum (Mo) is an element to be selectively added, and its content can be set to 0.2% or less (including 0%). Mo has a large effect of contributing to the improvement of strength and is effective in securing strength since it does not deteriorate the wettability of molten metal such as zinc. Even if it exceeds 0.2%, there is no problem, but it is not economically preferable since the effect increase is not so large any more. In one embodiment of the present invention, the Mo may be limited to 0.1% or less.
  • Ti titanium
  • the content of titanium (Ti) is preferably 0.1% or less (including 0%).
  • Ti is a nitride-forming element and has an effect of reducing the concentration of N in the steel, so that a small amount of Ti can be added as needed. If it exceeds 0.1%, the carbon concentration and the strength of the martensite are reduced due to the precipitation of additional carbide in addition to the removal of the solid solution N. Therefore, the upper limit can be limited to 0.1%.
  • the antimony (Sb) is a component selectively added to improve the surface quality of the plating, and the content of Sb is preferably 0.05% or less (including 0).
  • Sb is added, Sb is concentrated in the surface layer of the steel sheet, and the surface diffusion of Si, Mn, Al and the like is relatively suppressed, thereby improving the plating performance as a whole.
  • it exceeds 0.05% the effect of inhibiting surface diffusion of Si, Mn and Al during annealing is deteriorated, so that it is preferable to be limited to 0.05%.
  • Nb 0.1% or less (including 0%)
  • Niobium (Nb) is optionally added, and the content of Nb is preferably 0.1% or less. Nb is segregated in the form of carbide in the austenite grain boundaries to suppress the coarsening of the austenite grains during the annealing heat treatment to increase the strength. When the Nb content exceeds 0.1%, the amount of alloy iron is increased due to excessive alloying amount.
  • the content of boron (B) is preferably 0.005% or less.
  • Steel B can be added selectively to ensure strength. However, when the content of B exceeds 0.005%, the steel is concentrated on the annealed surface and the plating ability is greatly reduced.
  • the remainder of the present invention is iron (Fe).
  • impurities which are not intended from the raw material or the surrounding environment may be inevitably incorporated, so that it can not be excluded. These impurities are not specifically mentioned in this specification, as they are known to any person skilled in the art of steel making.
  • the manufacturing method of the high strength hot dip galvanized steel sheet of the present invention is not necessarily limited to the following manufacturing method.
  • the base steel sheet 1 when the base steel sheet 1 is simply annealed, the film-like oxide 2 is formed on the surface, so that even if plating is performed on the surface, the plating is not performed or the plating layer is not adhered, Unlike the conventional technique (a) in which the gap 5 is generated and the plating layer 3 is peeled off, in order to manufacture the hot-dip galvanized steel sheet having the above-described excellent plating property in the present invention (b) When iron oxide (2) is applied to the surface and annealing is performed, plating inhibiting elements such as Si, Mn or Al existing in the high-strength steel sheet form oxide (4) on the island near the iron oxide while reducing the iron oxide. . When such a steel sheet is plated, it is possible to prevent the problem that the unplated or the plating layer 3 is peeled off.
  • the plating interfering elements diffuse to the surface of the steel sheet to form a wide oxide film, thereby greatly reducing the plating adhesion.
  • the oxide is formed on the island because it diffuses near the dispersed iron oxide to form an oxide.
  • the manufacturing method of the present invention includes the steps of preparing a base steel sheet; Applying iron oxide to the prepared ground steel sheet; Annealing the iron oxide coated steel sheet; And hot dip galvanizing the annealed ground steel sheet.
  • the iron oxide used in one embodiment of the present invention may be one or a mixture of two or more selected from FeO, Fe 3 O 4 and Fe 2 O 3 . According to one embodiment of the present invention, these iron oxides can be used in combination with a rolling oil or a resin, in which case uniform coating and coating may be possible. In one embodiment of the present invention, the size (spherical equivalent diameter) of the iron oxide may be between 50 nm and 5 mu m.
  • the size of the iron oxide may be set to 5 ⁇ or less in order to prevent the iron oxide from falling off the steel sheet during annealing to cause a defect in the shape of a steel sheet.
  • the average interval of the iron oxide may be set to 0.5 to 5 ⁇ ⁇ .
  • the reasons for determining the interval of the iron oxide are as described above.
  • the annealing atmosphere it is necessary to control the atmosphere and the temperature at the time of annealing so as to prevent oxidation of Fe in the base steel sheet and to cause oxidation reaction of elements such as Si, Mn, and Al.
  • the dew point temperature can be maintained at 10 ° C or less during annealing. Also, considering the ability to maintain the atmosphere in a realistic production line, in one embodiment of the present invention, the dew point temperature during annealing may be set at -60 ⁇ or higher.
  • the hydrogen content in the atmospheric gas at the time of annealing can be set to 3% or more by volume. Even if the hydrogen content is increased, there is no particular technical problem. However, in one embodiment of the present invention, the hydrogen content can be set to 70% or less in consideration of economical efficiency.
  • the temperature of the steel sheet at the time of annealing may be 600 ° C or higher. However, considering the lifetime of the annealing furnace, the steel sheet temperature may be set at 950 ° C or lower. In one embodiment of the present invention, the steel sheet can be recrystallized within the annealing temperature range.
  • the time after reaching the target temperature for annealing may be set to 5 seconds or more.
  • the annealing time may be limited to 120 seconds or less in one embodiment of the present invention since the annealing time may be somewhat long, but it may cause a rise in cost. In the case of doubling up to recrystallization annealing, the annealing time may also be helpful in obtaining a uniform recrystallized structure.
  • a cooling step may follow.
  • cooling can be carried out at an average cooling rate of 5 to 100 DEG C / sec. .
  • the cooling may be performed in a primary cooling mode and a secondary cooling mode, and the secondary cooling rate may be greater than the primary cooling rate.
  • the primary cooling may be performed to 600 to 700 ⁇ ⁇ , after which secondary cooling may be performed.
  • the method may further include a step of cold-rolling the steel sheet before the annealing step. That is, when the steel sheet coated with iron oxide on its surface is cold-rolled, the iron oxide can be inserted right under the surface of the cold-rolled steel sheet, and an element such as Si, Mn or Al forms an oxide around the iron oxide Can be more easily achieved.
  • iron oxide may be applied using a separate coating equipment to firmly bond to the surface of the steel sheet. That is, in one embodiment of the present invention, iron oxide may be sprayed onto the surface of a steel sheet by using an apparatus capable of spraying and coating iron oxide such as thermal spray or AD (Aerosol Deposition) coating, In this case, the iron oxide can be firmly bonded to the steel sheet surface without cold rolling after coating.
  • a separate coating equipment capable of spraying and coating iron oxide such as thermal spray or AD (Aerosol Deposition) coating
  • the method may further include the step of pickling the surface of the steel sheet before applying the iron oxide to the surface of the steel sheet, if necessary.
  • the pickling can be done in the usual way and does not limit the conditions in particular.
  • the step of hot-dip galvanizing the steel sheet may follow.
  • the hot dip galvanizing method is not particularly limited, but in one embodiment of the present invention, when zinc is employed as the metal to be plated, it contains 0.13 to 0.3% of Al and the remainder is composed of Zn and unavoidable impurities, The steel sheet is immersed in a galvanizing bath maintained at a predetermined temperature, and then taken out to regulate the amount of deposited metal, followed by cooling to produce a hot-dip galvanized steel sheet.
  • the Al content of the plating bath is less than 0.13%, formation of the Fe-Al alloy phase formed at the interface between the base iron and the plating layer is suppressed and plating separation occurs. Therefore, the lower limit is preferably limited to 0.13%.
  • the Al content is more than 0.3%, the Al content in the plating layer increases and the weldability is deteriorated.
  • the steel sheet when zinc plating is performed, the steel sheet can be reheated to 400 to 550 ° C before plating. That is, in order to form the alloying suppressing layer formed by elution of Fe without delay, the reheating temperature may be 400 ⁇ or higher. However, if the temperature is too high, a phase transformation may occur in some high-strength steels and the desired material can not be satisfied. Therefore, the upper limit of the reheating temperature may be set to 550 ° C.
  • the plating bath temperature is limited to 440 to 500 ° C. Below 440 ⁇ , the viscosity of the zinc increases and the rollability of the roll in the plating bath lowers. When the temperature exceeds 500 ⁇ , the evaporation of zinc increases, which is not preferable.
  • iron oxide partially or wholly reduced by Si, Mn, Al or the like is present within 5 ⁇ in the depth direction from the surface of the steel sheet and Si, Mn , Al and the like are concentrated and exist in an oxide form.
  • the base steel sheet to which the iron oxide is applied may be a hot-rolled steel sheet or a cold-rolled steel sheet.
  • the base steel sheet of the present invention can be produced by conventional hot rolling or cold rolling, and the manufacturing conditions are not particularly limited, but the following is a non-limiting example according to one embodiment of the present invention.
  • reheating the steel slab satisfying the composition to a temperature between 1100 and 1300 ° C; Finishing the reheated steel slab to a finish temperature of the finishing hot rolling temperature Ar3 or higher;
  • the hot-rolled steel sheet may be manufactured by winding the hot-rolled steel sheet at a temperature of 700 ° C or less. If necessary, the cold-rolled steel sheet may be manufactured by pickling the hot-rolled steel sheet followed by cold rolling.
  • the slab satisfying the above composition is reheated to a temperature range of 1100 to 1300 ° C. If the reheating temperature is lower than 1100 ° C, there is a problem that the hot rolling load sharply increases. If the reheating temperature is higher than 1300 ° C, the reheating cost increases and the surface scale amount increases.
  • the finishing hot rolling temperature of the reheated slab is limited to not less than Ar3 (the temperature at which ferrite starts to appear when the austenite is cooled), which is below the Ar3, and the ferrite + And there is a fear of problems such as defective shape or sheet breakage due to the fluctuation of the hot rolling load due to this.
  • the steel sheet After the hot rolling, the steel sheet is wound. At this time, when the coiling temperature exceeds 700 ⁇ ⁇ , the oxide film on the surface of the steel sheet may be excessively generated to cause defects, so that the coiling temperature is limited to 700 ⁇ ⁇ or less.
  • the hot-rolled steel sheet can be obtained by the above-mentioned process, and the hot-dip galvanized steel sheet of the present invention can be obtained by applying the iron oxide on the surface of the hot-rolled steel sheet, annealing and plating the surface.
  • the hot-dip galvanized steel sheet of the present invention may be obtained by subjecting the hot-rolled steel sheet to pickling and cold rolling to obtain a cold-rolled steel sheet, coating the surface with iron oxide, annealing and plating.
  • the pickling and cold rolling conditions are not particularly limited and ordinary methods can be used.
  • the steel having the composition shown in Table 1 below was melted to prepare a slab.
  • the produced slab was maintained at 1200 ° C for 1 hour, cooled to 600 ° C at 900 ° C, which is the temperature of Ar3 or higher, and then cooled to 100 ° C by keeping it in a warming furnace for 1 hour to simulate the winding process.
  • the cold-rolled hot-rolled steel sheet was pickled at 60 ° C in a 17% by volume HCl solution for 30 seconds to remove the scale of the steel sheet.
  • the pickled steel sheet was coated with the following Table 2, and the steel sheet coated with the iron oxide was cold-rolled at a reduction ratio of 50%. It was confirmed that the iron oxide was evenly distributed on the surface of the steel sheet by cold rolling. At this time, iron oxide was mixed with rolling oil to distribute the iron oxide more uniformly.
  • the steel sheet was subjected to annealing (conducted in a 5% hydrogen + 95% nitrogen atmosphere) and hot-dip galvanizing under the conditions shown in Table 3.
  • the remainder excluding Al was Zn.
  • the amount of plating adhered was adjusted to 60 g / m 2 on one side, and the steel sheet was reheated before entering the plating bath to adjust the temperature to 470 ° C.
  • the steel composition, annealing and plating conditions of Inventive Examples 1 and 2 and Comparative Example 1 were all applied equally, and Fe oxide was classified into the inventive example and the comparative example depending on whether or not Fe oxide was used.
  • Inventive Samples 3, 4 and 5 and Comparative Example 2 were also applied in the same manner for steel composition, annealing condition, plating condition, and the like, but using Fe oxide was set differently.
  • the iron oxide was inserted and annealed from the surface of the steel sheet, it was confirmed that the iron oxide was reduced to elements such as Si, Mn and Al after the iron oxide was present within a depth of 5 ⁇ m from the surface of the steel sheet. Therefore, there was a region where the iron oxide was reduced to a depth of 5 ⁇ ⁇ from the surface of the steel sheet, and a complex oxide of Si, Mn and Al was present in the vicinity. Some of the oxides of Si, Mn, and Al are also present on the surface of the steel sheet, but there is no problem that the problem of unplated and adhesion of the plating deteriorates even when hot-dip galvanizing is performed because reduced iron or iron oxide exists thereon.
  • oxides such as Si, Mn and Al in the form of film are widely present on the surface of the base steel sheet, and it is difficult to secure the adhesion of the plating layer or the surface quality and the adhesion of the plating layer.
  • Comparative Example 1 the surface quality of Comparative Example 1 was not ensured.
  • Comparative Example 2 the reason why the surface quality and the adhesion of the plating layer were not ensured was that the content of Si was relatively high in Comparative Example 2 and the annealing temperature was about 60 ° C And the amount of Si and Mn diffusing to the surface during annealing was high.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Thermal Sciences (AREA)
  • Physics & Mathematics (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Heat Treatment Of Sheet Steel (AREA)
  • Coating With Molten Metal (AREA)

Abstract

La présente invention concerne une tôle d'acier galvanisée par immersion à chaud, à résistance élevée, possédant une excellente propriété de revêtement, et son procédé de fabrication. Selon un aspect de la présente invention, la tôle d'acier galvanisée par immersion à chaud, à résistance élevée, peut comprendre : une tôle d'acier de base ; une couche galvanisée par immersion à chaud formée sur la tôle d'acier de base ; et un oxyde d'au moins un élément choisi parmi Si, Mn et Al, formé dans une phase d'îlot entre la tôle d'acier de base et la couche galvanisée par immersion à chaud.
PCT/KR2018/016300 2017-12-24 2018-12-20 Tôle d'acier galvanisée par immersion à chaud, à résistance élevée, possédant une excellente propriété de revêtement, et son procédé de fabrication Ceased WO2019124997A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
KR10-2017-0178926 2017-12-24
KR1020170178926A KR102010076B1 (ko) 2017-12-24 2017-12-24 도금성이 우수한 고강도 용융아연도금강판 및 그 제조방법

Publications (1)

Publication Number Publication Date
WO2019124997A1 true WO2019124997A1 (fr) 2019-06-27

Family

ID=66993574

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/KR2018/016300 Ceased WO2019124997A1 (fr) 2017-12-24 2018-12-20 Tôle d'acier galvanisée par immersion à chaud, à résistance élevée, possédant une excellente propriété de revêtement, et son procédé de fabrication

Country Status (2)

Country Link
KR (1) KR102010076B1 (fr)
WO (1) WO2019124997A1 (fr)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN119563055A (zh) * 2022-06-17 2025-03-04 浦项股份有限公司 钢板及其制造方法
KR20250092386A (ko) * 2023-12-14 2025-06-24 주식회사 포스코 도금강판 및 그 제조방법

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20120075260A (ko) * 2010-12-28 2012-07-06 주식회사 포스코 도금밀착성이 우수한 용융도금강판 및 그 제조방법
KR20130075499A (ko) * 2011-12-27 2013-07-05 주식회사 포스코 고망간 열연 아연도금강판 및 그 제조방법
KR20130077907A (ko) * 2011-12-28 2013-07-09 주식회사 포스코 도금표면 품질 및 도금밀착성이 우수한 용융아연도금강판 및 그 제조방법
KR20140081616A (ko) * 2012-12-21 2014-07-01 주식회사 포스코 도금성 및 도금밀착성이 우수한 초고강도 용융아연도금강판 및 그 제조방법
KR101758485B1 (ko) * 2015-12-15 2017-07-17 주식회사 포스코 표면품질 및 점 용접성이 우수한 고강도 용융아연도금강판 및 그 제조방법

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20120075260A (ko) * 2010-12-28 2012-07-06 주식회사 포스코 도금밀착성이 우수한 용융도금강판 및 그 제조방법
KR20130075499A (ko) * 2011-12-27 2013-07-05 주식회사 포스코 고망간 열연 아연도금강판 및 그 제조방법
KR20130077907A (ko) * 2011-12-28 2013-07-09 주식회사 포스코 도금표면 품질 및 도금밀착성이 우수한 용융아연도금강판 및 그 제조방법
KR20140081616A (ko) * 2012-12-21 2014-07-01 주식회사 포스코 도금성 및 도금밀착성이 우수한 초고강도 용융아연도금강판 및 그 제조방법
KR101758485B1 (ko) * 2015-12-15 2017-07-17 주식회사 포스코 표면품질 및 점 용접성이 우수한 고강도 용융아연도금강판 및 그 제조방법

Also Published As

Publication number Publication date
KR102010076B1 (ko) 2019-08-12
KR20190077179A (ko) 2019-07-03

Similar Documents

Publication Publication Date Title
WO2017105064A1 (fr) Tôle en acier galvanisé à chaud à haute résistance ayant d'excellentes qualité de surface et soudabilité par points, et procédé de fabrication de celle-ci
WO2020130631A1 (fr) Tôle d'acier galvanisée à haute résistance ayant une excellente soudabilité par point de résistance électrique et son procédé de fabrication
WO2016105115A1 (fr) Tôle d'acier galvanisée à chaud à haute résistance présentant d'excellentes caractéristiques en termes de qualité de surface, d'adhérence du revêtement et d'aptitude au moulage et procédé de production de cette tôle d'acier
WO2015093793A1 (fr) Tôle en acier plaqué pour formage par presse à chaud ayant d'excellentes soudabilité et résistance à la corrosion, élément de formage et procédé pour sa fabrication
WO2016098964A1 (fr) Tôle d'acier à haute résistance laminée à froid ayant une faible non-uniformité de matériau et une excellente aptitude au formage, tôle d'acier galvanisée par immersion à chaud et procédé de fabrication associé
WO2017111525A1 (fr) Tôle en acier revêtue d'alliage d'aluminium-fer pour formage par pressage à chaud, ayant d'excellentes résistance à la facture retardée par hydrogène, résistance au pelage et soudabilité et élément formé à chaud au moyen de celle-ci
WO2016104880A1 (fr) Élément de moulage hpf présentant une excellente résistance au délaminage et son procédé de fabrication
WO2013032173A2 (fr) Acier à teneur élevée en manganèse présentant une soudabilité supérieure et procédé de fabrication d'une feuille d'acier galvanisée par immersion à chaud à partir de cet acier
WO2017111449A1 (fr) Matériau en acier zingué par immersion à chaud haute résistance présentant d'excellentes propriétés de placage et son procédé de préparation
WO2018117724A1 (fr) Tôle d'acier laminée à chaud de résistance élevée et tôle d'acier laminée à froid d'excellente productivité continue, tôle d'acier galvanisée par immersion à chaud de résistance élevée présentant une excellente qualité de surface et une excellente adhérence de plaquage, et son procédé de fabrication
WO2017111428A1 (fr) Tôle d'acier laminée à froid à haute résistance présentant d'excellentes propriétés de ductilité, de formation de trous et de traitement de surface, tôle d'acier galvanisé dans un bain fondu, et son procédé de fabrication
WO2021125885A1 (fr) Tôle d'acier plaquée au zinc haute résistance sophistiquée ayant une excellente qualité de surface et une excellente aptitude au soudage par points par résistance électrique et son procédé de fabrication
WO2019124781A1 (fr) Tôle d'acier revêtue d'un placage à base de zinc ayant une excellente résistance au vieillissement à température ambiante et une excellente aptitude au durcissement par cuisson, et son procédé de fabrication
WO2021112581A1 (fr) Tôle en acier plaquée de zinc présentant une excellente résistance à la fatigue de soudures par points par résistance électrique et son procédé de fabrication
WO2017111533A1 (fr) Tôle d'acier à haute teneur en manganèse revêtue d'aluminium par immersion à chaud ayant une excellente adhérence du revêtement
WO2018105904A1 (fr) Plaque d'acier galvanisée à chaud ayant une excellente aptitude au durcissement à la cuisson et d'excellentes propriétés anti-vieillissement à température ambiante et procédé de fabrication associé
WO2022124812A1 (fr) Feuille d'acier recuite par galvanisation à haute résistance présentant une excellente résistance au poudrage et son procédé de fabrication
WO2018117703A1 (fr) Tôle d'acier plaquée à l'aluminium par immersion à chaud à haute teneur en manganèse dotée d'une excellente protection par électrode sacrificielle et d'une excellente aptitude au pliage et son procédé de fabrication
WO2019124997A1 (fr) Tôle d'acier galvanisée par immersion à chaud, à résistance élevée, possédant une excellente propriété de revêtement, et son procédé de fabrication
WO2019124807A1 (fr) Tôle d'acier présentant d'excellentes propriétés de durcissement par cuisson et une excellente résistance à la corrosion et son procédé de fabrication
WO2013100610A1 (fr) Tôle d'acier galvanisée laminée à chaud à teneur élevée en manganèse et son procédé de fabrication
WO2018117770A1 (fr) Tôle d'acier plaquée d'alliage à base d'aluminium ayant une excellente résistance à la corrosion de pièces de procédé
WO2023113099A1 (fr) Tôle d'acier pour pressage à chaud et pièce emboutie à chaud fabriquée à l'aide de celle-ci
WO2021125901A2 (fr) Tôle d'acier revêtue d'un dépôt d'alliage à base d'aluminium ayant une excellente aptitude au façonnage et une excellente résistance à la corrosion, et son procédé de fabrication
WO2019124808A1 (fr) Tôle d'acier ayant d'excellentes propriétés de durcissement par cuisson et d'adhérence de placage et son procédé de fabrication

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 18890539

Country of ref document: EP

Kind code of ref document: A1

122 Ep: pct application non-entry in european phase

Ref document number: 18890539

Country of ref document: EP

Kind code of ref document: A1