EP2821520A1 - Method for the coating of steel flat products with a metallic protective layer and steel flat products with a metallic protective layer - Google Patents
Method for the coating of steel flat products with a metallic protective layer and steel flat products with a metallic protective layer Download PDFInfo
- Publication number
- EP2821520A1 EP2821520A1 EP13174979.8A EP13174979A EP2821520A1 EP 2821520 A1 EP2821520 A1 EP 2821520A1 EP 13174979 A EP13174979 A EP 13174979A EP 2821520 A1 EP2821520 A1 EP 2821520A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- flat steel
- steel product
- coating
- ions
- bath
- 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.)
- Granted
Links
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 151
- 239000010959 steel Substances 0.000 title claims abstract description 151
- 238000000576 coating method Methods 0.000 title claims description 72
- 239000011248 coating agent Substances 0.000 title claims description 57
- 238000000034 method Methods 0.000 title claims description 37
- 239000011241 protective layer Substances 0.000 title description 3
- 230000004907 flux Effects 0.000 claims abstract description 65
- 239000000155 melt Substances 0.000 claims abstract description 24
- 229910052710 silicon Inorganic materials 0.000 claims abstract description 22
- 229910052782 aluminium Inorganic materials 0.000 claims abstract description 21
- 229910052750 molybdenum Inorganic materials 0.000 claims abstract description 16
- 229910052759 nickel Inorganic materials 0.000 claims abstract description 16
- 239000012535 impurity Substances 0.000 claims abstract description 15
- 229910052742 iron Inorganic materials 0.000 claims abstract description 14
- 229910052698 phosphorus Inorganic materials 0.000 claims abstract description 12
- 238000004519 manufacturing process Methods 0.000 claims abstract description 11
- 229910052748 manganese Inorganic materials 0.000 claims abstract description 10
- 229910052712 strontium Inorganic materials 0.000 claims abstract description 10
- 229910001414 potassium ion Inorganic materials 0.000 claims abstract description 9
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 claims abstract description 8
- PTFCDOFLOPIGGS-UHFFFAOYSA-N Zinc dication Chemical compound [Zn+2] PTFCDOFLOPIGGS-UHFFFAOYSA-N 0.000 claims abstract description 7
- 150000002500 ions Chemical class 0.000 claims abstract description 7
- BHPQYMZQTOCNFJ-UHFFFAOYSA-N Calcium cation Chemical compound [Ca+2] BHPQYMZQTOCNFJ-UHFFFAOYSA-N 0.000 claims abstract description 6
- 229910001424 calcium ion Inorganic materials 0.000 claims abstract description 6
- 229910052744 lithium Inorganic materials 0.000 claims abstract description 6
- 229910001415 sodium ion Inorganic materials 0.000 claims abstract description 6
- JLVVSXFLKOJNIY-UHFFFAOYSA-N Magnesium ion Chemical compound [Mg+2] JLVVSXFLKOJNIY-UHFFFAOYSA-N 0.000 claims abstract description 5
- -1 ammonium ions Chemical class 0.000 claims abstract description 5
- 229910001425 magnesium ion Inorganic materials 0.000 claims abstract description 5
- 239000012736 aqueous medium Substances 0.000 claims abstract description 4
- 239000007864 aqueous solution Substances 0.000 claims abstract description 3
- 239000011701 zinc Substances 0.000 claims description 78
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 31
- 238000005554 pickling Methods 0.000 claims description 29
- 238000001035 drying Methods 0.000 claims description 18
- 239000011777 magnesium Substances 0.000 claims description 17
- 238000003618 dip coating Methods 0.000 claims description 12
- 239000011253 protective coating Substances 0.000 claims description 12
- 239000003795 chemical substances by application Substances 0.000 claims description 11
- 229910052749 magnesium Inorganic materials 0.000 claims description 11
- 229910052719 titanium Inorganic materials 0.000 claims description 10
- 229910052725 zinc Inorganic materials 0.000 claims description 10
- 229910052802 copper Inorganic materials 0.000 claims description 9
- 229910052757 nitrogen Inorganic materials 0.000 claims description 9
- 229910052758 niobium Inorganic materials 0.000 claims description 8
- 229910052720 vanadium Inorganic materials 0.000 claims description 8
- 229910052796 boron Inorganic materials 0.000 claims description 7
- 229910052804 chromium Inorganic materials 0.000 claims description 7
- 239000011575 calcium Substances 0.000 claims description 6
- 239000011734 sodium Substances 0.000 claims description 6
- 229910001220 stainless steel Inorganic materials 0.000 claims description 6
- 238000007654 immersion Methods 0.000 claims description 5
- 239000000126 substance Substances 0.000 claims description 5
- 229910052717 sulfur Inorganic materials 0.000 claims description 5
- 229910052791 calcium Inorganic materials 0.000 claims description 4
- 229910052708 sodium Inorganic materials 0.000 claims description 4
- 239000010935 stainless steel Substances 0.000 claims description 4
- 229910052726 zirconium Inorganic materials 0.000 claims description 4
- QGZKDVFQNNGYKY-UHFFFAOYSA-O Ammonium Chemical compound [NH4+] QGZKDVFQNNGYKY-UHFFFAOYSA-O 0.000 claims description 3
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 claims description 3
- 229910000746 Structural steel Inorganic materials 0.000 claims description 3
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 claims description 3
- 230000003213 activating effect Effects 0.000 claims description 2
- 238000010438 heat treatment Methods 0.000 claims description 2
- 229910052700 potassium Inorganic materials 0.000 claims description 2
- 239000011591 potassium Substances 0.000 claims description 2
- 239000011573 trace mineral Substances 0.000 claims 1
- 235000013619 trace mineral Nutrition 0.000 claims 1
- 229910052799 carbon Inorganic materials 0.000 abstract description 3
- 239000002609 medium Substances 0.000 description 21
- 239000011651 chromium Substances 0.000 description 11
- 230000008569 process Effects 0.000 description 11
- 230000004913 activation Effects 0.000 description 9
- 230000000694 effects Effects 0.000 description 9
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 8
- 238000002474 experimental method Methods 0.000 description 8
- 239000010410 layer Substances 0.000 description 8
- 230000007797 corrosion Effects 0.000 description 7
- 238000005260 corrosion Methods 0.000 description 7
- 238000000137 annealing Methods 0.000 description 6
- 238000004140 cleaning Methods 0.000 description 6
- 239000002253 acid Substances 0.000 description 5
- 239000000758 substrate Substances 0.000 description 5
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 4
- 229910052797 bismuth Inorganic materials 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- 238000002161 passivation Methods 0.000 description 4
- 239000010953 base metal Substances 0.000 description 3
- 238000011161 development Methods 0.000 description 3
- 230000018109 developmental process Effects 0.000 description 3
- 238000007598 dipping method Methods 0.000 description 3
- 238000001704 evaporation Methods 0.000 description 3
- 230000008020 evaporation Effects 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- 238000012360 testing method Methods 0.000 description 3
- NLXLAEXVIDQMFP-UHFFFAOYSA-N Ammonia chloride Chemical compound [NH4+].[Cl-] NLXLAEXVIDQMFP-UHFFFAOYSA-N 0.000 description 2
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 description 2
- PXGOKWXKJXAPGV-UHFFFAOYSA-N Fluorine Chemical compound FF PXGOKWXKJXAPGV-UHFFFAOYSA-N 0.000 description 2
- NPYPAHLBTDXSSS-UHFFFAOYSA-N Potassium ion Chemical compound [K+] NPYPAHLBTDXSSS-UHFFFAOYSA-N 0.000 description 2
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 2
- 229910001297 Zn alloy Inorganic materials 0.000 description 2
- 229910045601 alloy Inorganic materials 0.000 description 2
- 239000000956 alloy Substances 0.000 description 2
- 238000005275 alloying Methods 0.000 description 2
- WATWJIUSRGPENY-UHFFFAOYSA-N antimony atom Chemical compound [Sb] WATWJIUSRGPENY-UHFFFAOYSA-N 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- JCXGWMGPZLAOME-UHFFFAOYSA-N bismuth atom Chemical compound [Bi] JCXGWMGPZLAOME-UHFFFAOYSA-N 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 238000001816 cooling Methods 0.000 description 2
- 239000013078 crystal Substances 0.000 description 2
- 239000003599 detergent Substances 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- 229910052738 indium Inorganic materials 0.000 description 2
- APFVFJFRJDLVQX-UHFFFAOYSA-N indium atom Chemical compound [In] APFVFJFRJDLVQX-UHFFFAOYSA-N 0.000 description 2
- 229910052745 lead Inorganic materials 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 239000002893 slag Substances 0.000 description 2
- 239000000779 smoke Substances 0.000 description 2
- 229910052716 thallium Inorganic materials 0.000 description 2
- BKVIYDNLLOSFOA-UHFFFAOYSA-N thallium Chemical compound [Tl] BKVIYDNLLOSFOA-UHFFFAOYSA-N 0.000 description 2
- 229910052718 tin Inorganic materials 0.000 description 2
- 238000009736 wetting Methods 0.000 description 2
- 229910018125 Al-Si Inorganic materials 0.000 description 1
- 229910021364 Al-Si alloy Inorganic materials 0.000 description 1
- 229910000789 Aluminium-silicon alloy Inorganic materials 0.000 description 1
- 229910018520 Al—Si Inorganic materials 0.000 description 1
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 1
- FGUUSXIOTUKUDN-IBGZPJMESA-N C1(=CC=CC=C1)N1C2=C(NC([C@H](C1)NC=1OC(=NN=1)C1=CC=CC=C1)=O)C=CC=C2 Chemical compound C1(=CC=CC=C1)N1C2=C(NC([C@H](C1)NC=1OC(=NN=1)C1=CC=CC=C1)=O)C=CC=C2 FGUUSXIOTUKUDN-IBGZPJMESA-N 0.000 description 1
- 206010013786 Dry skin Diseases 0.000 description 1
- 229910001335 Galvanized steel Inorganic materials 0.000 description 1
- 229910001209 Low-carbon steel Inorganic materials 0.000 description 1
- GIYXAJPCNFJEHY-UHFFFAOYSA-N N-methyl-3-phenyl-3-[4-(trifluoromethyl)phenoxy]-1-propanamine hydrochloride (1:1) Chemical compound Cl.C=1C=CC=CC=1C(CCNC)OC1=CC=C(C(F)(F)F)C=C1 GIYXAJPCNFJEHY-UHFFFAOYSA-N 0.000 description 1
- WGLPBDUCMAPZCE-UHFFFAOYSA-N Trioxochromium Chemical compound O=[Cr](=O)=O WGLPBDUCMAPZCE-UHFFFAOYSA-N 0.000 description 1
- 150000007513 acids Chemical class 0.000 description 1
- 235000019270 ammonium chloride Nutrition 0.000 description 1
- 229910052787 antimony Inorganic materials 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 229910052793 cadmium Inorganic materials 0.000 description 1
- 238000006388 chemical passivation reaction Methods 0.000 description 1
- 229910000423 chromium oxide Inorganic materials 0.000 description 1
- 238000005097 cold rolling Methods 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 239000000356 contaminant Substances 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 230000006353 environmental stress Effects 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 239000011737 fluorine Substances 0.000 description 1
- 229910052731 fluorine Inorganic materials 0.000 description 1
- 239000008397 galvanized steel Substances 0.000 description 1
- 238000005246 galvanizing Methods 0.000 description 1
- 238000005244 galvannealing Methods 0.000 description 1
- 238000005098 hot rolling Methods 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 1
- WABPQHHGFIMREM-UHFFFAOYSA-N lead(0) Chemical compound [Pb] WABPQHHGFIMREM-UHFFFAOYSA-N 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000007747 plating Methods 0.000 description 1
- 230000008092 positive effect Effects 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 238000010926 purge Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
- 239000011833 salt mixture Substances 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 238000004227 thermal cracking Methods 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 230000003313 weakening effect Effects 0.000 description 1
Images
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
- C23C2/30—Fluxes or coverings on molten baths
-
- 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
- C23C2/024—Pretreatment of the material to be coated, e.g. for coating on selected surface areas by cleaning or etching
Definitions
- the invention relates to a method for coating flat steel products with a Zn- or Al-based metallic protective coating and flat steel products which are coated with such a protective coating.
- the "flat steel products" to be coated in the context of the invention are tapes or sheets produced from steel by hot or cold rolling, as well as blanks and blanks obtained therefrom.
- Steel flat products made from corrosion-sensitive steels and intended for use in an environment where there is an increased risk of corrosion are usually provided with a metallic protective coating which protects the respective steel substrate against corrosive attacks.
- a proven for the application of such a coating process is the hot dip coating, in which the steel flat product is passed through a melt bath after pretreatment within a short immersion time, so that when leaving the melt bath, a coating of defined thickness adheres to the flat steel product.
- the thickness of the coating can be adjusted by suitable stripping, the Flat steel product as it exits the melt bath.
- This process also known in technical terms as "hot dip finishing", produces flat steel products that have a significantly longer product life compared to untreated flat steel products.
- the steel flat product to be coated in each case passes through the process steps "cleaning”, "annealing gas activation of the surface” and "hot-dip coating” successively and without interruption.
- the activation of the surface is typically carried out in a continuous furnace via a heterogeneous annealing gas-metal reaction under a H 2 -N 2 -containing annealing atmosphere at temperatures of more than 700 ° C.
- hot rolled wide strips are to be provided with a hot-dip coating, they can be descaled before the annealing treatment in a pickling device. This is achieved by using mordants containing a correspondingly aggressive acid, in particular hydrochloric or sulfuric acid, the existing on the hot-rolled broadband tinder.
- narrow bands whose width is limited to max. 600 mm is limited, with the proven for broadband coating processes do not cover costs.
- broad bands are therefore longitudinally divided into narrow bands of predetermined width, which then pass through a pickling device parallel to one another in order to loosen and remove any oxide residues and other contaminants present on the narrow bands.
- pickling agent residues are rinsed from the narrow strips and the narrow strips are passed through a flux bath.
- fluxen the fluxing agent prevents re-passivation of the activated surface until immersion in the coating bath.
- the narrow bands still pass through a drying oven parallel to each other, in which the flux is dried to the extent that it adheres securely to the narrow bands, but not yet burned.
- the flux thus ensures a good and uniform wettability of the narrow bands in the subsequently passed melt bath.
- the corrosion protection coating is applied as a Zn coating.
- the melt bath typically has a temperature of up to 700 ° C in this case.
- a chemical passivation may be added to the respective surface coating in order to protect the protective layer against the effects of moisture (see the brochure "Hot-dip galvanized steel strip", published by ThyssenKrupp Steel Europe AG, 2011, www.thyssenkrupp-steel-europe.com/tiny /cgJ/download.pdf).
- Steels with a significant alloy content of Cr and Ni are characterized by particularly good chemical resistance and high corrosion resistance.
- This product feature is based on the formation of a stable Chromium oxide layer, which passivates the steel surface effectively against external influences even at higher temperatures. Mo additionally supports this passivation. Therefore, steel grades with a Cr content> 10.5 wt .-% are also referred to as rust, heat and acid resistant (RHS) steels or short as "stainless steels”.
- RHS heat and acid resistant
- B. Mn or N the austenitic microstructure towards lower temperatures, which can be used selectively to improve the mechanical material properties.
- Ni-alloyed full austenites have a significantly better environmental stress rating. Due to these excellent material properties, there is a great potential for use in Ni-alloyed flat steel products for high and low temperature applications in the automotive vehicle structure, chemical apparatus construction, mechanical and plant engineering as well as for decorative elements.
- the object of the invention was to provide a Indicate industrially cost-effective method, which allows for optimal reproducibility of the coating result, the economic production of specially protected against corrosive attacks flat steel products.
- the invention is based on the idea that, instead of the usual in the hot dip coating for cleaning and activation of the surfaces to be coated surfaces of broad bands annealing according to the well-known from the prior art approach a flux treatment followed by drying of the applied in the flux treatment on the flat steel product Flux.
- the flux used according to the invention is modified in such a way that optimum coating results result for flat steel products which consist of a wide range of steels of very different alloyed steels.
- the procedure according to the invention makes it possible to significantly improve compared to piece galvanizing Efficiency in a continuous cycle To provide flat steel products with metallic protective coatings.
- a considerable saving of energy and resources is achieved and a cost-effective and environmentally friendly hot dipping refinement, in particular of narrow strips, whose width is limited to a maximum of 600 mm.
- several such narrow bands can also pass through the method according to the invention in parallel.
- the procedure according to the invention is suitable for the application of metallic coatings both on Znals and on Al base.
- the steel flat product processed in accordance with the invention can be delivered in the cold or hot rolled state with an already pregelled or unpickled surface.
- the advantages of the method according to the invention have an especially significant effect on the processing of unpickled hot-rolled strip, whereby the procedure according to the invention has proven to be particularly economical in the processing of narrow strip.
- step b) the flat steel product to be coated in each case passes through a pickling tank in which scale which adheres to it is removed.
- the pickling time is optimally 10 to 120 s.
- the surface of the flat steel product to be coated is already activated during pickling.
- a pickling agent temperature of 30-100 ° C has been found to be particularly advantageous for the effectiveness of the pickling process.
- pickling temperatures and pickling times in the stated ranges an optimum cleaning effect is achieved and an excessive graining of the grain boundaries on the steel surface is avoided.
- excessive evaporation loss is avoided. This is especially true if the maximum pickling temperature is limited to 70 ° C.
- the Fe concentration in the pickling bath should be between 5-130 g / l in order to also support optimum pickling efficiency.
- pickling agent remaining on the flat steel product is removed by rinsing the flat steel product with an aqueous medium.
- the rinsing time here is optimally 10 to 30 seconds at a detergent temperature of optimally 30 to 100 ° C, especially 30 to 70 ° C.
- the operation d in which the flat steel product undergoes fluxing.
- the purpose of this treatment is to complete the activation of the already activated during the pickling surface of the flat steel product and to prevent re-passivation.
- the flat steel product is passed through a flux, which is adjusted in accordance with the invention in the manner indicated above by the addition of ammonium chloride so that reliable good coating results are achieved.
- Ammonium ions are contained in contents of 5-12 g / l, chloride ions in contents of 210-250 g / l and zinc ions in contents of 140-160 g / l in the flux medium forming the flux medium according to the invention drying a ZnCl 2 / NH 4 Cl salt mixture is formed on the steel surface. This forms by thermal cracking during drying HCl, which ensures activation both against the steel surface and against the top slag of the coating. If it exceeds or falls below the specified limits, activation is not effective or burning of the flux medium during drying is too strong. In particular, when the chloride ion content is too low, insufficient surface slag reduction is exhibited. If the proportion of chloride and zinc ions is too high, chlorhydroxozinc acids can form in the liquid flux medium, unnecessarily increasing the dissolution of iron into the flux medium vessel.
- Potassium ions are present in the flux medium at levels of 30-40 g / l because the addition of potassium ions stabilizes the flux against attack or reaction with the Al of the plating bath. This reduces the development of smoke when immersing the steel strip in the coating bath, which in turn has a positive effect on environmental and employee protection. If the potassium ion content of the flux medium is too low, this effect is not sufficiently effective. On the other hand, if the potassium ion content is too high, the activation effect of the flux medium may be too weak.
- calcium ions in contents of 0.5 to 1.5 g / l, sodium ions in contents of 0.5 to 1.5 g / l and magnesium ions in contents of ⁇ 1 g / l in the invention used Fluxmedium be present.
- Ca, Na and Mg support the effect of the potassium ions required in the flux medium and reduce the surface tension of the flux. This improves the wetting of the steel surface by the flux medium.
- increasing the respective contents above the respective upper limit does not further reduce the smoke development, but can lead to a weakening of the activation effect of the flux medium.
- Ions of Fe, Mn, Al, Mo, Ni, P, Si, Sr, Li may be present as unavoidable impurities in slight traces, the content of which should be less than 10 mg / l each.
- the density of the flux which is set in the range from 1.25 to 1.45 g / cm 3 , can influence the coating weight of the coating to be produced on the steel substrate. If the lower limit specified for the density of the flux medium according to the invention is not reached, the medium is too watery and the micro-cleaning effect of the steel surface is too low. If, in contrast, the upper limit for the density of the flux medium provided according to the invention is exceeded, the fluxing is too sharp and the grain boundaries on the steel surface can be attacked too strongly.
- the flux used according to the invention contributes to the particular effectiveness of the flux used according to the invention when its pH is 4 to 4.5. If the upper limit specified for the pH of the flux medium is exceeded, the medium is too watery and the ultrafine cleaning effect of the steel surface is too low. If the lower limit specified for the pH of the flux medium is exceeded, the fluxing is again too sharp and the grain boundaries on the steel surface can be attacked too strongly.
- step e) the steel flat product emerging from the flux bath is dried and brought to the inlet temperature, with which it enters the subsequently passed melt bath.
- the minimum temperature should be so high that the flux medium entrained on the flat steel product surface from the flux bath is sufficiently dried to avoid wetting disturbances during the coating in the melt bath.
- the drying temperature should not be too high to avoid burning off the flux medium.
- the flat steel product is heated to a temperature of 100 - 230 ° C.
- the belt inlet temperature should be held during drying for at least 10 seconds to adequately heat the flat steel product.
- the maximum permissible drying time depends on the performance of the particular drying plant used. Practical experiments have shown that a maximum of 30 s is useful for the systems used in today's practice.
- flat steel products made of stainless CrNi steels covered by the abovementioned alloying instruction and processed in accordance with the invention can be coated with any of the above-described coatings, and particularly flat steel products made of a structural steel of the type specified above can be well protected with a coated in accordance with the invention ZM coating against corrosion.
- Flat steel products, which are made of stainless steel and provided in accordance with the invention with an AS coating, are particularly suitable for high temperature applications.
- the AS coating protects such flat steel products against the formation of tarnish.
- the melt bath temperature is 430-700 ° C, typically 430-530 ° C, while at a melt bath which is Al-based, the bath temperature typically up to 780 ° C, in particular 650-780 ° C, is.
- hot dip coated flat steel product is to be thermally aftertreated (galvannealed) in-line to produce an Fe-Zn alloy coating, it has been found useful to adjust the melt bath to form an ZF coating on the steel substrate.
- the resulting hot dip coated steel flat product may be subjected to passivation by a corresponding chemical treatment or temper rolling to improve dimensional stability and its mechanical properties.
- the plant 1 for the hot dip coating of a flat rolled product P provided as a hot rolled coil and a coil C comprises, in a successive line-up in the conveying direction F, an uncoiling station 2, a pickling station 3, a rinsing station 4, a fluxing station 5, a drying station 6, a hot-dip station 7 and a cooling station 8 and a coiling station 9.
- the flat steel product P to be coated is unwound from the respective coil C and first passes through the pickling station 3 and subsequently the rinsing station 4 before it enters the fluxing station 5.
- the flat steel product P emerging from the flux station 5 passes through the drying station 6 and is then directed into the melt bath S of the hot-dip dipping station 7.
- the steel flat product P emerging from the molten bath S then passes through the cooling station 8, where it is cooled to room temperature, before it is wound again into a coil in the coiling station 9.
- the respectively processed flat steel products P have undergone a conventional hydrochloric acid-based pickling bath B in the pickling station 3, which has been heated to a temperature TB and which has passed from the respective section of the respective flat steel product P within a pickling period tB.
- the flat steel products P in the rinsing device 4 have passed through a rinsing bath V consisting of demineralized water, which has been heated to a temperature TS and has been discharged from the respective section of the respective flat steel product P within a rinsing time tS.
- a rinsing bath V consisting of demineralized water, which has been heated to a temperature TS and has been discharged from the respective section of the respective flat steel product P within a rinsing time tS.
- the flat steel products P in the flux station 5 have been passed through a flux bath X which has passed through the respective section of the respective flat steel product P within a duration tF and has a temperature TF, a pH pH_F and a density r-F.
- a flux bath X which has passed through the respective section of the respective flat steel product P within a duration tF and has a temperature TF, a pH pH_F and a density r-F.
- twelve different composite flux baths X have been used in the experiments.
- the twelve compositions X1 - X12 of the flux baths X are given in Table 2.
- the flat steel products are dried and brought to the respective bath inlet temperature TE.
- the thickness of the respectively applied hot-dip coating in the flat steel products has been set in a manner known per se by means of a stripping device, not shown here.
- Tables 3a, 3b the respectively set operating parameters are summarized for a total of 55 tests.
- Table 3a contains the experiments carried out according to the invention, which have provided a good, error-free coating result, while in the tables 3b, 3c, the experiments are summarized that have resulted in incorrect coating results.
- the respective steel W1 - W7 which consisted of each processed flat steel product P, the respective temperature TB of the mordant, the pickling time tB, the temperature TS of the detergent and the purge time tS in the Flux station 5 flux flux X1 - X12, the duration tF, in which the respective flat steel product has passed the respective flux bath X1 - X12, the respective flux bath temperature TF, the respective pH value pH_F and the respective density rF of the respective flux bath X1 - X12 , the respective drying or bath inlet temperature TE, the composition of the respective melt bath S, the temperature TBad of the respective melt bath S and in each case on one of coated sides of the flat steel product P reached Auflagethe AG indicated.
- the residence time in the drying station was 20 s in each case and in the melt bath 10 s in each case.
- FIGS. 2 and 4 show that the two variants of the method, in which the respective flat steel product P has been hot-dip-coated with a ZM coating Z, lead to approximately identical coatings, independently of the material of the respective steel substrate.
- the respective coating Z has a covering layer of Zn mixed crystals ( ⁇ phase) with ZnMg 2 phases pronounced between the Zn mixed crystals and an Fe-Zn alloy layer Fe-Zn formed between the flat steel product P and the covering layer on, via which the cover layer is permanently adhered to the steel substrate formed by the flat steel product P.
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Coating With Molten Metal (AREA)
Abstract
Die Erfindung ermöglicht es, auf großtechnisch betriebssichere Weise ein gegen korrosive Angriffe besonders geschütztes Stahlflachprodukt zu erzeugen, indem das Stahlflachprodukt im kontinuierlichen Durchlauf a) bereitgestellt wird, b) gebeizt wird, c) mit einem wässrigen Medium gespült wird, d) durch ein Flussmittelbad geleitet wird, das aus einer wässrigen Lösung besteht, die neben prozess- und herstellungsbedingten Verunreinigungen 210 - 250 g/l Chlorid-Ionen und zusätzlich 140 - 160 g/l Zink-Ionen, 5 - 12 g/l Ammonium-Ionen oder 30 - 40 g/l Kalium-Ionen und optional zusätzlich jeweils 0,5 - 1,5 g/l Natrium-Ionen oder Kalzium-Ionen und max. 1 g/l Magnesium-Ionen und Spuren von Ionen der Elemente "Al, Fe, Mn, Mo, Ni, P, Sr, Si und Li" enthält, wobei die Dichte des Flussmittelbads mindestens 1,25 g/cm 3 und höchstens 1,45 g/cm 3 beträgt, e) getrocknet und auf eine Badeintrittstemperatur von 100 - 230 °C erwärmt wird, f) in einem Schmelzenbad schmelztauchbeschichtet wird, und g) optional thermisch, chemisch oder mechanisch nachbehandelt wird.The invention makes it possible to produce in a commercially reliable manner a particularly protected against corrosive attacks flat steel product by the flat steel product in a continuous flow a) is provided, b) is pickled, c) is rinsed with an aqueous medium, d) passed through a flux bath which consists of an aqueous solution containing 210- 250 g / l of chloride ions and additionally 140-160 g / l of zinc ions, 5-12 g / l of ammonium ions or 30-40 in addition to process- and production-related impurities g / l potassium ions and optionally additionally 0.5 - 1.5 g / l sodium ions or calcium ions and max. 1 g / l of magnesium ions and traces of ions of the elements "Al, Fe, Mn, Mo, Ni, P, Sr, Si and Li", wherein the density of the flux bath is at least 1.25 g / cm 3 and at most 1 , 45 g / cm 3, e) is dried and heated to a bath inlet temperature of 100-230 ° C, f) hot-dip coated in a melt bath, and g) optionally post-treated thermally, chemically or mechanically.
Description
Die Erfindung betrifft ein Verfahren zum Beschichten von Stahlflachprodukten mit einem auf Zn- oder Al-basierenden metallischen Schutzüberzug sowie Stahlflachprodukte, die mit einem solchen Schutzüberzug belegt sind.The invention relates to a method for coating flat steel products with a Zn- or Al-based metallic protective coating and flat steel products which are coated with such a protective coating.
Bei den im Sinne der Erfindung zu beschichtenden "Stahlflachprodukten" handelt es sich um aus Stahl durch Warm- oder Kaltwalzen erzeugte Bänder oder Bleche sowie daraus gewonnene Zuschnitte und Platinen.The "flat steel products" to be coated in the context of the invention are tapes or sheets produced from steel by hot or cold rolling, as well as blanks and blanks obtained therefrom.
Stahlflachprodukte, die aus korrosionsempfindlichen Stählen hergestellt sind und in einer Umgebung eingesetzt werden sollen, bei der ein erhöhtes Korrosionsrisiko besteht, werden üblicherweise mit einem metallischen Schutzüberzug versehen, der das jeweilige Stahlsubstrat gegen korrosive Angriffe schützt. Ein zum Auftrag eines solchen Überzugs bewährtes Verfahren ist das Schmelztauchbeschichten, bei dem das Stahlflachprodukt nach einer Vorbehandlung innerhalb einer kurzen Tauchdauer durch ein Schmelzenbad geleitet wird, so dass beim Verlassen des Schmelzenbades ein Überzug definierter Dicke auf dem Stahlflachprodukt haftet. Die Dicke des Überzugs kann dabei durch geeignete Abstreifeinrichtungen eingestellt werden, die das Stahlflachprodukt beim Austritt aus dem Schmelzenbad passiert.Steel flat products made from corrosion-sensitive steels and intended for use in an environment where there is an increased risk of corrosion are usually provided with a metallic protective coating which protects the respective steel substrate against corrosive attacks. A proven for the application of such a coating process is the hot dip coating, in which the steel flat product is passed through a melt bath after pretreatment within a short immersion time, so that when leaving the melt bath, a coating of defined thickness adheres to the flat steel product. The thickness of the coating can be adjusted by suitable stripping, the Flat steel product as it exits the melt bath.
Durch dieses in der Fachsprache auch "Schmelztauchveredelung" bezeichnete Vorgehen werden Stahlflachprodukte erhalten, die gegenüber unveredelten Stahlflachprodukten eine deutlich verlängerte Produktlebensdauer besitzen.This process, also known in technical terms as "hot dip finishing", produces flat steel products that have a significantly longer product life compared to untreated flat steel products.
Es sind verschiedenste Varianten von Verfahren bekannt, die bei optimierter Wirtschaftlichkeit jeweils eine optimale Haftung des Überzugs und optimale Gebrauchseigenschaften des mit dem Überzug versehenen Stahlflachprodukts gewährleisten sollen. Als eine dieser Entwicklungen zu nennen ist hier der Vorschlag, durch zusätzliche Zugabe von Mg zu einem Zn-Schmelzenbad den durch den so legierten Überzug bewirkten Korrosionsschutz deutlich zu steigern. Beispiele für auf diesem Vorschlag basierende Beschichtungsverfahren sind in der
Jeweils entscheidend für den Erfolg bei der Beschichtung von Stahlflachprodukten ist eine ausreichende Aktivierung der zu beschichtenden Oberfläche. Darüber hinaus muss sichergestellt sein, dass die betreffende Oberfläche beim Eintauchen in das jeweilige Schmelzenbad weitestgehend frei von Verunreinigungen und Oxiden ist, die das Beschichtungsergebnis stören könnten.Decisive for success in the coating of flat steel products is sufficient activation of the surface to be coated. In addition, it must be ensured that the surface in question when immersed in the respective melt bath is largely free of impurities and oxides that could disturb the coating result.
Mit im kontinuierlichen Durchlauf erfolgenden Schmelztauchbeschichtungsverfahren lassen sich kalt- oder warmgewalzte Stahlbänder mit Breiten von mehr als 600 mm, so genannte "Breitbänder", besonders kosteneffektiv mit einem Schutzüberzug versehen. Bei den in der Praxis eingesetzten Verfahren dieser Art durchläuft das jeweils zu beschichtende Stahlflachprodukt nacheinander und unterbrechungsfrei die Prozessschritte "Reinigung", "Glühgasaktivierung der Oberfläche" und "Schmelztauchbeschichtung". Wie beispielsweise in der
In der Praxis hat sich herausgestellt, dass sich Schmalbänder, deren Breite auf max. 600 mm beschränkt ist, mit den für Breitbänder bewährten Beschichtungsverfahren nicht kostendeckend beschichten lassen. In der Praxis werden daher Breitbänder in Schmalbänder vorgegebener Breite längsgeteilt, die dann parallel zueinander eine Beizeinrichtung durchlaufen, um auf den Schmalbändern vorhandene oxidische Rückstände und sonstige Verschmutzungen zu lösen und zu entfernen. Anschließend werden Beizmittelrückstände von den Schmalbändern gespült und die Schmalbänder durch ein Flussmittelbad geleitet. Durch diesen in der Fachsprache auch als "Fluxen" bekannten Vorgang werden einerseits die zu beschichtenden Oberflächen der Schmalbänder weiter gereinigt und gleichzeitig aktiviert. Andererseits wird durch das Fluxmittel eine Rückpassivierung der aktivierten Oberfläche bis zum Eintauchen in das Beschichtungsbad verhindert. Anschließend durchlaufen die Schmalbänder immer noch parallel zueinander einen Trocknungsofen, in dem das Flussmittel soweit angetrocknet wird, dass es sicher auf den Schmalbändern haftet, jedoch noch nicht abbrennt. Das Flussmittel stellt so eine gute und gleichmäßige Benetzbarkeit der Schmalbänder im anschließend durchlaufenen Schmelzenbad sicher. Üblicherweise wird der Korrosionsschutzüberzug als Zn-Überzug aufgebracht. Das dann auf Zn basierende Schmelzenbad, in das die Schmalbänder wiederum parallel zueinander gefördert werden, hat dazu typischerweise eine Temperatur von 470 °C. Es ist jedoch auch möglich, die Schmalbänder mit einer auf Al basierenden Beschichtung schmelztauchzubeschichten. Das Schmelzenbad hat in diesem Fall typischerweise eine Temperatur von bis zu 700 °C. An die jeweilige Oberflächenbeschichtung kann sich eine chemische Passivierung anschließen, um auch die Schutzschicht vor Feuchtigkeitseinwirkung zu schützen (s. Broschüre "Feuerverzinkter Bandstahl", veröffentlicht von der ThyssenKrupp Steel Europe AG, Stand 2011, www.thyssenkrupp-steel-europe.com/tiny/cgJ/download.pdf).In practice, it has been found that narrow bands whose width is limited to max. 600 mm is limited, with the proven for broadband coating processes do not cover costs. In practice, broad bands are therefore longitudinally divided into narrow bands of predetermined width, which then pass through a pickling device parallel to one another in order to loosen and remove any oxide residues and other contaminants present on the narrow bands. Subsequently, pickling agent residues are rinsed from the narrow strips and the narrow strips are passed through a flux bath. Through this in the jargon also known as "Fluxen" process on the one hand to be coated surfaces of the narrow bands continue to be cleaned and at the same time activated. On the other hand, the fluxing agent prevents re-passivation of the activated surface until immersion in the coating bath. Subsequently, the narrow bands still pass through a drying oven parallel to each other, in which the flux is dried to the extent that it adheres securely to the narrow bands, but not yet burned. The flux thus ensures a good and uniform wettability of the narrow bands in the subsequently passed melt bath. Usually, the corrosion protection coating is applied as a Zn coating. The then Zn-based melt bath, in which the narrow strips are in turn conveyed parallel to each other, typically has a temperature of 470 ° C for this purpose. However, it is also possible to hot dip the narrow ribbons with a coating based on Al. The melt bath typically has a temperature of up to 700 ° C in this case. A chemical passivation may be added to the respective surface coating in order to protect the protective layer against the effects of moisture (see the brochure "Hot-dip galvanized steel strip", published by ThyssenKrupp Steel Europe AG, 2011, www.thyssenkrupp-steel-europe.com/tiny /cgJ/download.pdf).
Wie eingangs erwähnt, werden in der voranstehend erläuterten Weise üblicherweise Stahlflachprodukte beschichtet, die in hohem Maße korrosionsempfindlich sind.As mentioned above, flat steel products which are highly susceptible to corrosion are usually coated in the above-described manner.
Stähle mit einem deutlichen Legierungsanteil an Cr und Ni zeichnen sich durch eine besonders gute chemische Beständigkeit und hohen Korrosionswiderstand aus. Diese Produkteigenschaft basiert auf der Bildung einer stabilen Chromoxidschicht, welche die Stahloberfläche auch bei höheren Temperaturen wirksam gegen äußere Einflüsse passiviert. Mo unterstützt diese Passivierung zusätzlich. Daher werden Stahlgüten mit einem Cr-Anteil > 10,5 Gew.-% auch als rost-, hitze- und säurebeständige (RHS)-Stähle oder kurz als "rostfreie Stähle" bezeichnet. Ni als Legierungselement in Stahl stabilisiert ähnlich wie z. B. Mn oder N den austenitischen Gefügezustand zu tieferen Temperaturen hin, was gezielt genutzt werden kann, um die mechanischen Werkstoffeigenschaften zu verbessern. Vollaustenitische Stahlgüten mit > 8 Gew.-% Ni besitzen weiterhin keinen Spröd-Duktil-Übergang, was Tieftemperaturanwendungen ermöglicht. Im Vergleich zu hoch-Mn-legierten Stahlgüten weisen Ni-legierte Vollaustenite eine deutlich bessere Umweltbeanspruchungseignung auf. Aufgrund dieser hervorragenden Werkstoffeigenschaften besteht ein großes Einsatzpotential für Ni-legierte Stahlflachprodukte für Hoch- und Tieftemperaturanwendungen u. a. in der automobilen Fahrzeugstruktur, dem chemischen Apparatebau, Maschinen- und Anlagenbau sowie für dekorative Elemente.Steels with a significant alloy content of Cr and Ni are characterized by particularly good chemical resistance and high corrosion resistance. This product feature is based on the formation of a stable Chromium oxide layer, which passivates the steel surface effectively against external influences even at higher temperatures. Mo additionally supports this passivation. Therefore, steel grades with a Cr content> 10.5 wt .-% are also referred to as rust, heat and acid resistant (RHS) steels or short as "stainless steels". Ni stabilized as alloying element in steel similar to such. B. Mn or N the austenitic microstructure towards lower temperatures, which can be used selectively to improve the mechanical material properties. Full austenitic steels with> 8 wt% Ni also do not have a brittle-ductile transition, allowing for low temperature applications. In comparison to high-Mn-alloyed steel grades, Ni-alloyed full austenites have a significantly better environmental stress rating. Due to these excellent material properties, there is a great potential for use in Ni-alloyed flat steel products for high and low temperature applications in the automotive vehicle structure, chemical apparatus construction, mechanical and plant engineering as well as for decorative elements.
Trotz dieser hervorragenden spezifischen Werkstoffeigenschaften, insbesondere gegenüber schädlichen Umwelteinflüssen, können die Einsatzqualitäten CrNilegierter Stähle durch eine metallische Beschichtung zusätzlich gesteigert werden. Auch hierzu kommen in der Praxis Schmelztauchbeschichtungsverfahren der voranstehend erläuterten Art zum Einsatz.Despite these excellent specific material properties, especially against harmful environmental influences, the use of CrNilegierter steels can be further increased by a metallic coating. In practice, hot dip coating methods of the type described above are also used for this purpose.
Vor dem Hintergrund des voranstehend erläuterten Standes der Technik bestand die Aufgabe der Erfindung darin, ein großtechnisch kostengünstig durchführbares Verfahren anzugeben, das bei optimaler Reproduzierbarkeit des Beschichtungsergebnisses die wirtschaftliche Erzeugung von gegen korrosive Angriffe besonders geschützten Stahlflachprodukten ermöglicht.Against the background of the prior art explained above, the object of the invention was to provide a Indicate industrially cost-effective method, which allows for optimal reproducibility of the coating result, the economic production of specially protected against corrosive attacks flat steel products.
Diese Aufgabe ist erfindungsgemäß dadurch gelöst worden, dass beim Beschichten eines Stahlflachprodukts die in Anspruch 1 angegebenen Arbeitsschritte durchlaufen werden.This object has been achieved according to the invention, that during the coating of a flat steel product, the steps specified in claim 1 are performed.
Vorteilhafte Ausgestaltungen der Erfindung sind in den abhängigen Ansprüchen angegeben und werden nachfolgend wie der allgemeine Erfindungsgedanke im Einzelnen erläutert.Advantageous embodiments of the invention are specified in the dependent claims and are explained below as the general inventive concept in detail.
Die Erfindung geht von dem Gedanken aus, an Stelle der bei der Schmelztauchbeschichtung zur Reinigung und Aktivierung der zu beschichtenden Oberflächen von Breitbändern üblichen Glühbehandlung entsprechend der aus dem Stand der Technik ebenfalls grundsätzlich bekannten Vorgehensweise eine Fluxbehandlung mit anschließender Antrocknung des bei der Fluxbehandlung auf das Stahlflachprodukt aufgetragenen Flussmittels durchzuführen. Dabei ist das erfindungsgemäß zum Einsatz kommende Flussmittel so modifiziert, dass sich für Stahlflachprodukte, die aus einer großen Bandbreite unterschiedlichst legierter Stähle bestehen, optimale Beschichtungsergebnisse ergeben.The invention is based on the idea that, instead of the usual in the hot dip coating for cleaning and activation of the surfaces to be coated surfaces of broad bands annealing according to the well-known from the prior art approach a flux treatment followed by drying of the applied in the flux treatment on the flat steel product Flux. In this case, the flux used according to the invention is modified in such a way that optimum coating results result for flat steel products which consist of a wide range of steels of very different alloyed steels.
Um dies zu leisten, umfasst ein erfindungsgemäßes Verfahren zum Beschichten eines Stahlflachprodukts mit einem metallischen, auf Zn oder Al basierenden Schutzüberzug folgende im kontinuierlichen Durchlauf absolvierte Arbeitsschritte:
- a) Bereitstellen des Stahlflachprodukts;
- b) Beizen des Stahlflachprodukts zur Entfernung von auf dem Stahlflachprodukt haftendem Zunder und zur Aktivierung der Oberfläche des Stahlflachprodukts;
- c) Entfernen von auf dem gebeizten Stahlflachprodukt nach dem Beizen vorhandenem Beizmittel durch Spülen des Stahlflachprodukts mit einem wässrigen Medium;
- d) Durchleiten des gebeizten und gespülten Stahlflachprodukts durch ein Flussmittelbad, das aus einer wässrigen Lösung besteht, die neben prozess- und herstellungsbedingten Verunreinigungen Chlorid-Ionen und mindestens Ionen eines der Elemente aus der Gruppe "Zink, Ammonium und Kalium" sowie optional zusätzlich Ionen der Elemente "Na, Ca und Mg" ebenso optional Spuren der Elemente "Al, Fe, Mn, Mo, Ni, P, Sr, Si und Li" mit der Maßgabe enthält, dass
- die Gesamtkonzentration an Chlorid-Ionen c(Cl-) mindestens 210 g/l und höchstens 250 g/l,
- die Gesamtkonzentration an Zink-Ionen c(Zn2+) mindestens 140 g/l und höchstens 160 g/l,
- die Gesamtkonzentration an Ammonium-Ionen c(NH4 +) mindestens 5 g/l und höchstens 12 g/l,
- die Gesamtkonzentration an Kalium-Ionen c(K+) mindestens 30 g/l und höchstens 40 g/l,
- die Gesamtkonzentration an optional vorhandenen Natrium-Ionen c(Na+) mindestens 0,5 g/l und höchstens 1,5 g/l,
- die Gesamtkonzentration an optional vorhandenen Kalzium-Ionen c(Ca2+) mindestens 0,5 g/l und höchstens 1,5 g/l,
- die Gesamtkonzentration an optional vorhandenen Magnesium-Ionen c(Mg+) höchstens 1 g/l,
- die Gehalte an den in Spuren vorhandenen Ionen der Elemente Al, Fe, Mn, Mo, Ni, P, Si, Sr und Li höchstens 10 mg/l und
- die Dichte des Flussmittelbads mindestens 1,25 g/cm3 und höchstens 1,45 g/cm3 beträgt, wobei insbesondere keine Ionen der Elemente Fluor, Zinn, Blei, Indium, Thallium, Antimon, Wismut oder Bor im Flussmittelbad enthalten sind;
- e) Trocknen des aus dem Flussmittelbad austretenden Stahlflachprodukts und Erwärmen des Stahlflachprodukts auf eine 100 - 230 °C betragende Badeintrittstemperatur;
- f) Schmelztauchbeschichten des Stahlflachprodukts mit einem auf Zn oder Al basierenden metallischen Schutzüberzugs in einem Schmelzenbad, in das das Stahlflachprodukt mit der Badeintrittstemperatur eintritt;
- g) optional durchgeführtes thermisches, chemisches oder mechanisches Nachbehandeln des mit dem Schutzüberzug schmelztauchbeschichteten Stahlflachprodukts.
- a) providing the flat steel product;
- b) pickling the flat steel product to remove scale adhering to the flat steel product and activating the surface of the flat steel product;
- c) removing pickling agent present on the pickled steel flat product after pickling by rinsing the flat steel product with an aqueous medium;
- d) passing the pickled and rinsed steel flat product through a flux bath, which consists of an aqueous solution, in addition to process and manufacturing-related impurities chloride ions and at least one of the elements from the group "zinc, ammonium and potassium" and optionally additionally the ions Elements "Na, Ca and Mg" also optionally contain traces of the elements "Al, Fe, Mn, Mo, Ni, P, Sr, Si and Li" with the proviso that
- the total concentration of chloride ions c (Cl - ) at least 210 g / l and at most 250 g / l,
- the total concentration of zinc ions c (Zn 2+) is at least 140 g / l and at most 160 g / l,
- the total concentration of ammonium ions c (NH 4 + ) at least 5 g / l and at most 12 g / l,
- the total concentration of potassium ions c (K + ) at least 30 g / l and at most 40 g / l,
- the total concentration of optional sodium ions c (Na + ) at least 0.5 g / l and at most 1.5 g / l,
- the total concentration of optionally present calcium ions c (Ca 2+ ) at least 0.5 g / l and at most 1.5 g / l,
- the total concentration of optionally available magnesium ions c (Mg + ) at most 1 g / l,
- the contents of the trace ions of the elements Al, Fe, Mn, Mo, Ni, P, Si, Sr and Li are at most 10 mg / l and
- the density of the flux bath is at least 1.25 g / cm 3 and at most 1.45 g / cm 3 , in particular no ions of the elements fluorine, tin, lead, indium, thallium, antimony, bismuth or boron are contained in the flux bath;
- e) drying the flat steel product leaving the flux bath and heating the flat steel product to a bath inlet temperature of 100-230 ° C;
- f) hot dip coating the flat steel product with a Zn or Al based metallic protective coating in a melt bath into which the flat steel product enters at the bath inlet temperature;
- g) optional thermal, chemical or mechanical aftertreatment of the flat hot-dip coated with the protective coating.
Die erfindungsgemäße Vorgehensweise erlaubt es, bei gegenüber einer Stückverzinkung erheblich verbesserter Wirtschaftlichkeit im kontinuierlichen Durchlauf Stahlflachprodukte mit metallischen Schutzüberzügen zu versehen. Durch Verzicht auf einen energieintensiven Glühprozessschritt wird eine erhebliche Energie- und Betriebsmitteleinsparung erzielt und eine kosteneffektive und umweltschonende Schmelztauchveredelung insbesondere von Schmalbändern ermöglicht, deren Breite auf höchstens 600 mm beschränkt ist. Mehrere solcher Schmalbänder können selbstverständlich auch das erfindungsgemäße Verfahren parallel durchlaufen.The procedure according to the invention makes it possible to significantly improve compared to piece galvanizing Efficiency in a continuous cycle To provide flat steel products with metallic protective coatings. By dispensing with an energy-intensive annealing process step, a considerable saving of energy and resources is achieved and a cost-effective and environmentally friendly hot dipping refinement, in particular of narrow strips, whose width is limited to a maximum of 600 mm. Of course, several such narrow bands can also pass through the method according to the invention in parallel.
Dabei eignet sich die erfindungsgemäße Vorgehensweise für den Auftrag von metallischen Beschichtungen sowohl auf Znals auch auf Al-Basis.The procedure according to the invention is suitable for the application of metallic coatings both on Znals and on Al base.
Praktische Versuche haben beispielsweise gute Beschichtungsergebnisse ergeben, wenn das im Arbeitsschritt
- a) bereitgestellte Stahlflachprodukt aus einem Baustahl hergestellt ist, der neben Eisen und herstellungsbedingt unvermeidbaren Verunreinigungen (in Gew.-%)
- C: 0,001- 0,7 %;
- Mn: 0,10 - 2,0 %;
- Al: 0,01 - 2,0 %;
sowie jeweils optional eines oder mehrere Elemente aus der Gruppe "Si, P, S, Cr, Cu, Mo, N, Ni, Nb, Ti, V, Zr, B" mit der Maßgabe enthält, dass für die Gehalte an den optional zugegebenen Elementen gilt:- Si: 0,001 - 2,0 %;
- P: bis zu 0,055 %;
- S: bis zu 0,055 %;
- Cr: 0,01 - 2,0 %
- Cu:
bis zu 0,6 %; - Mo:
bis zu 0,2 %; - N: bis zu 0,030 %;
- Ni:
bis zu 2,1 %; - Nb:
bis zu 0,2 %; - Ti:
bis zu 0,2 %; - V:
bis zu 0,2 %; - Zr:
bis zu 0,2 %; - B: bis zu 0,0060.
- a) provided steel flat product is made of a structural steel, in addition to iron and production-related unavoidable impurities (in wt .-%)
- C: 0.001-0.7%;
- Mn: 0.10-2.0%;
- Al: 0.01-2.0%;
and in each case optionally one or more elements from the group "Si, P, S, Cr, Cu, Mo, N, Ni, Nb, Ti, V, Zr, B" with the proviso that for the contents of the optionally added Elements applies:- Si: 0.001-2.0%;
- P: up to 0.055%;
- S: up to 0.055%;
- Cr: 0.01 - 2.0%
- Cu: up to 0.6%;
- Mo: up to 0.2%;
- N: up to 0.030%;
- Ni: up to 2.1%;
- Nb: up to 0.2%;
- Ti: up to 0.2%;
- V: up to 0.2%;
- Zr: up to 0.2%;
- B: up to 0.0060.
Das erfindungsgemäße Verfahren eignet sich aber auch zum Schmelztauchbeschichten von Stahlflachprodukten, die ein ferritisches, austenitsches, Mehrphasen- oder Duplex-Gefüge besitzen und aus einem nicht rostenden CrNi-Stahl bestehen können, der neben Eisen und herstellungsbedingt unvermeidbaren Verunreinigungen (in Gew.-%)
- C: 0,001- 0,5 %;
- Mn: 0,10 - 6,0 %;
- Al: 0,01 - 2,0 %;
- Cr: 5,0 - 30,0 %;
- Ni: 2,00 - 30,0 %
sowie jeweils optional eines oder mehrere Elemente aus der Gruppe "Si, Cu, Mo, N, Nb, Ti, V" mit der Maßgabe enthält, dass für die Gehalte an den optional zugegebenen Elementen gilt:- Si: 0,001 - 2,0 %;
- Cu:
bis zu 2,0 %; - Mo:
bis zu 5,0 %; - N:
bis zu 0,2 %; - Nb: bis zu 1,0 %;
- Ti: bis zu 1,0 %;
- V:
bis zu 0,5 %.
- C: 0.001-0.5%;
- Mn: 0.10 - 6.0%;
- Al: 0.01-2.0%;
- Cr: 5.0-30.0%;
- Ni: 2.00 - 30.0%
and in each case optionally one or more elements from the group "Si, Cu, Mo, N, Nb, Ti, V" with the proviso that the following applies to the contents of the optionally added elements:- Si: 0.001-2.0%;
- Cu: up to 2.0%;
- Mo: up to 5.0%;
- N: up to 0.2%;
- Nb: up to 1.0%;
- Ti: up to 1.0%;
- V: up to 0.5%.
Das jeweils erfindungsgemäß verarbeitete Stahlflachprodukt kann im kalt- oder warmgewalzten Zustand mit bereits vorgebeizter oder ungebeizter Oberfläche angeliefert werden. Die Vorteile des erfindungsgemäßen Verfahrens wirken sich besonders bei der Verarbeitung von ungebeiztem Warmband aus, wobei sich die erfindungsgemäße Vorgehensweise bei der Verarbeitung von Schmalband als besonders wirtschaftlich herausgestellt hat.The steel flat product processed in accordance with the invention can be delivered in the cold or hot rolled state with an already pregelled or unpickled surface. The advantages of the method according to the invention have an especially significant effect on the processing of unpickled hot-rolled strip, whereby the procedure according to the invention has proven to be particularly economical in the processing of narrow strip.
Im Arbeitsschritt b) durchläuft das jeweils zu beschichtende Stahlflachprodukt ein Beizbecken, in dem auf ihm haftender Zunder entfernt wird. Die Beizdauer beträgt dabei optimaler Weise 10 - 120 s. Neben der Reinigung erfolgt bereits beim Beizen eine Aktivierung der Oberfläche des zu beschichtenden Stahlflachprodukts. Als Beizmittel können an sich zu diesem Zweck bekannte Flüssigkeiten eingesetzt werden, die auf einer Säure, insbesondere Salz- oder Schwefelsäure, basieren. Hierbei hat sich für die Effektivität des Beizvorgangs eine Beizmitteltemperatur von 30 - 100 °C als besonders vorteilhaft herausgestellt. Bei in den genannten Bereichen liegenden Beiztemperaturen und Beizzeiten wird ein optimaler Reinigungseffekt erzielt und eine zu starke Anbeizung der Korngrenzen an der Stahloberfläche vermieden. Weiterhin wird durch Einhaltung des erfindungsgemäß vorgegebenen Temperaturbereichs ein übermäßiger Verdampfungsverlust vermieden. Dies gilt insbesondere dann, wenn die maximale Beiztemperatur auf 70 °C beschränkt ist.In step b), the flat steel product to be coated in each case passes through a pickling tank in which scale which adheres to it is removed. The pickling time is optimally 10 to 120 s. In addition to the cleaning, the surface of the flat steel product to be coated is already activated during pickling. As a mordant known liquids can be used for this purpose, based on an acid, especially hydrochloric or sulfuric acid. Here, a pickling agent temperature of 30-100 ° C has been found to be particularly advantageous for the effectiveness of the pickling process. At pickling temperatures and pickling times in the stated ranges, an optimum cleaning effect is achieved and an excessive graining of the grain boundaries on the steel surface is avoided. Furthermore, by observing the temperature range prescribed according to the invention, excessive evaporation loss is avoided. This is especially true if the maximum pickling temperature is limited to 70 ° C.
Die Fe-Konzentration im Beizmittelbad sollte zwischen 5 - 130 g/l liegen, um ebenfalls eine optimale Wirksamkeit des Beizvorgangs zu unterstützen.The Fe concentration in the pickling bath should be between 5-130 g / l in order to also support optimum pickling efficiency.
Nach dem Beizen wird auf dem Stahlflachprodukt zurückgebliebenes Beizmittel durch Spülen des Stahlflachprodukts mit einem wässrigen Medium entfernt. Die Spülzeit beträgt hier optimalerweise 10 - 30 s bei einer Spülmitteltemperatur von optimalerweise 30 - 100 °C, insbesondere 30 - 70 °C. Durch Einhaltung dieser Spültemperatur- und Spülzeitbereiche ist ein effektives Abspülen der Restsäure gewährleistet, so dass Einschleppungen von Beizrückständen in das folgende Fluxbad vermieden werden. Wird die für die Spültemperatur angegebene Obergrenze überschritten, erhöht der verstärkte Verdampfungsverlust an Spülmedium die Betriebskosten. Die maximale Spültemperatur beträgt deshalb vorteilhafter Weise 70 °C.After pickling, pickling agent remaining on the flat steel product is removed by rinsing the flat steel product with an aqueous medium. The rinsing time here is optimally 10 to 30 seconds at a detergent temperature of optimally 30 to 100 ° C, especially 30 to 70 ° C. By adhering to these rinsing temperature and rinsing time ranges, an effective rinsing of the residual acid is ensured, so that the introduction of pickling residues into the subsequent flux bath is avoided. If the upper limit specified for the rinse temperature is exceeded, the increased evaporation loss of rinse medium increases the operating costs. The maximum rinsing temperature is therefore advantageously 70 ° C.
Besondere Bedeutung kommt beim erfindungsgemäßen Verfahren dem Arbeitsschritt d) zu, bei dem das Stahlflachprodukt ein Fluxen durchläuft. Der Zweck dieser Behandlung besteht darin, die Aktivierung der im Zuge des Beizens bereits aktivierten Oberfläche des Stahlflachprodukts zu vervollständigen und eine Rückpassivierung zu verhindern. Hierzu wird das Stahlflachprodukt durch ein Flussmittel geleitet, das nach Maßgabe der Erfindung in der oben angegebenen Weise durch die Zugabe von Ammoniumchlorid so eingestellt ist, dass betriebssicher gute Beschichtungsergebnisse erzielt werden.Of particular importance in the process according to the invention is the operation d), in which the flat steel product undergoes fluxing. The purpose of this treatment is to complete the activation of the already activated during the pickling surface of the flat steel product and to prevent re-passivation. For this purpose, the flat steel product is passed through a flux, which is adjusted in accordance with the invention in the manner indicated above by the addition of ammonium chloride so that reliable good coating results are achieved.
Ammonium-Ionen sind in Gehalten von 5 - 12 g/l, Chlorid-Ionen in Gehalten von 210 - 250 g/l und Zink-Ionen in Gehalten von 140 - 160 g/l im das erfindungsgemäß vorgegebenen Flussmittelbad bildenden Fluxmedium enthalten, damit während des Trocknens ein ZnCl2/NH4Cl-Salzgemisch an der Stahloberfläche entsteht. Dieses bildet durch thermische Spaltung während des Trocknens HCl, was eine Aktivierung sowohl gegenüber der Stahloberfläche als auch gegenüber der Oberschlacke des Beschichtungsbads sichert. Bei Über-/ oder Unterschreitung der angegebenen Grenzen ist die Aktivierung nicht effektiv oder das Abbrennen des Fluxmediums während des Trocknens zu stark. Insbesondere zeigt sich bei einem zu geringen Chlorid-Ionen-Anteil eine nicht ausreichende Reduktion von Oberflächenschlacke. Ist der Anteil an Chlorid- und Zink-Ionen zu hoch, können sich bereits im flüssigen Fluxmedium Chlorhydroxozinksäuren bilden, die die Eisenauflösung in den Fluxmediumkessel unnötig erhöhen.Ammonium ions are contained in contents of 5-12 g / l, chloride ions in contents of 210-250 g / l and zinc ions in contents of 140-160 g / l in the flux medium forming the flux medium according to the invention drying a ZnCl 2 / NH 4 Cl salt mixture is formed on the steel surface. This forms by thermal cracking during drying HCl, which ensures activation both against the steel surface and against the top slag of the coating. If it exceeds or falls below the specified limits, activation is not effective or burning of the flux medium during drying is too strong. In particular, when the chloride ion content is too low, insufficient surface slag reduction is exhibited. If the proportion of chloride and zinc ions is too high, chlorhydroxozinc acids can form in the liquid flux medium, unnecessarily increasing the dissolution of iron into the flux medium vessel.
Kalium-Ionen sind im Fluxmedium in Gehalten von 30 - 40 g/l vorhanden, da durch die Zugabe von Kalium-Ionen das Fluxmittel gegenüber dem Angriff oder der Reaktion mit dem Al des Beschichtungsbads stabilisiert wird. Dadurch reduziert sich die Rauchentwicklung beim Eintauchen des Stahlbands in das Beschichtungsbad, was sich wiederum positiv auf Umwelt- und den Mitarbeiterschutz auswirkt. Ist der Kalium-Ionen-Anteil des Fluxmediums zu gering, zeigt sich dieser Effekt nicht ausreichend effektiv. Ist der Kalium-Ionen-Gehalt dagegen zu hoch, kann der Aktivierungseffekt des Fluxmediums zu schwach sein. Jeweils optional können Kalzium-Ionen in Gehalten von 0,5 - 1,5 g/l, Natrium-Ionen in Gehalten von 0,5 - 1,5 g/l und Magnesium-Ionen in Gehalten von < 1 g/l im erfindungsgemäß verwendeten Fluxmedium vorhanden sein. Ca, Na und Mg unterstützen die Wirkung der im Fluxmittel pflichtweise vorhandenen Kalium--Ionen und reduzieren die Oberflächenspannung des Fluxmittels. Dies verbessert die Benetzung der Stahloberfläche durch das Fluxmedium. Eine Erhöhung der jeweiligen Gehalte über die jeweils zugeordnete Obergrenze hinaus verringert die Rauchentwicklung jedoch nicht weiter, sondern kann zu einer Schwächung des Aktivierungseffekts des Fluxmediums führen.Potassium ions are present in the flux medium at levels of 30-40 g / l because the addition of potassium ions stabilizes the flux against attack or reaction with the Al of the plating bath. This reduces the development of smoke when immersing the steel strip in the coating bath, which in turn has a positive effect on environmental and employee protection. If the potassium ion content of the flux medium is too low, this effect is not sufficiently effective. On the other hand, if the potassium ion content is too high, the activation effect of the flux medium may be too weak. In each case optionally calcium ions in contents of 0.5 to 1.5 g / l, sodium ions in contents of 0.5 to 1.5 g / l and magnesium ions in contents of <1 g / l in the invention used Fluxmedium be present. Ca, Na and Mg support the effect of the potassium ions required in the flux medium and reduce the surface tension of the flux. This improves the wetting of the steel surface by the flux medium. However, increasing the respective contents above the respective upper limit does not further reduce the smoke development, but can lead to a weakening of the activation effect of the flux medium.
Ionen von Fe, Mn, Al, Mo, Ni, P, Si, Sr, Li können als unvermeidbare Verunreinigungen in geringen Spuren vorhanden sein, wobei deren Gehalt jeweils weniger als 10 mg/l betragen soll.Ions of Fe, Mn, Al, Mo, Ni, P, Si, Sr, Li may be present as unavoidable impurities in slight traces, the content of which should be less than 10 mg / l each.
Optimale Ergebnisse der Flux-Behandlung ergeben sich dann, wenn die Eintauchdauer, über die der jeweils in das Flussmittelbad tauchende Abschnitt des Stahlflachprodukts dem Flussmittel ausgesetzt ist, 10 - 120 s beträgt. Die Wirksamkeit des Flussmittels kann dadurch gesteigert werden, dass seine Temperatur 40 - 100 °C, insbesondere 40 - 70 °C, beträgt. Bei Einhaltung dieser für die Eintauchdauer und die Fluxmitteltemperatur vorgegebenen Bereiche wird bei Vermeidung eines übermäßigen Verdampfungsverlustes ein optimaler Feinstreinigungseffekt der Stahloberfläche erzielt und ein übermäßiger Angriff der Korngrenzen an der Stahloberfläche vermieden.Optimal results of the flux treatment will result if the immersion time over which the section of the flat steel product immersed in the flux bath is exposed to the flux is 10-120 s. The effectiveness of the flux can be increased by the fact that its temperature 40-100 ° C, in particular 40-70 ° C, is. Adhering to these ranges specified for the immersion time and the flux temperature, an optimum Feinstreinigungseffekt the steel surface is achieved and avoids excessive attack of the grain boundaries on the steel surface while avoiding excessive evaporation loss.
Über die im Bereich von 1,25 - 1,45 g/cm3 eingestellte Dichte des Flussmittels kann dabei Einfluss auf das Auflagengewicht der auf dem Stahlsubstrat zu erzeugenden Beschichtung genommen werden. Wird die für die Dichte des Fluxmediums erfindungsgemäß vorgegebene Untergrenze unterschritten, ist das Medium zu wässrig und der Feinstreinigungseffekt der Stahloberfläche zu gering. Wird dagegen die für die Dichte des Fluxmediums erfindungsgemäß vorgesehene Obergrenze überschritten, ist das Fluxen zu scharf und die Korngrenzen an der Stahloberfläche können zu stark angegriffen werden.The density of the flux, which is set in the range from 1.25 to 1.45 g / cm 3 , can influence the coating weight of the coating to be produced on the steel substrate. If the lower limit specified for the density of the flux medium according to the invention is not reached, the medium is too watery and the micro-cleaning effect of the steel surface is too low. If, in contrast, the upper limit for the density of the flux medium provided according to the invention is exceeded, the fluxing is too sharp and the grain boundaries on the steel surface can be attacked too strongly.
Sollen beispielsweise Zn-basierte Überzüge mit einem Auflagengewicht von 400 - 600 g/m2 auf das jeweilige Stahlflachprodukt aufgebracht werden, so haben sich Flussmittelbäder mit einer Dichte von 1,25 - 1,35 g/cm3 bewährt. Sollen dagegen Zn-basierte Überzüge mit einem Auflagengewicht von weniger als 400 g/m2 auf das jeweilige Stahlflachprodukt aufgebracht werden, so haben sich Flussmittelbäder mit einer Dichte von >1,35 - 1,45 g/cm3 als günstig erwiesen.If, for example, Zn-based coatings with a coating weight of 400-600 g / m 2 are to be applied to the respective flat steel product, then flux baths having a density of 1.25-1.35 g / cm 3 have proven suitable. If, on the other hand, Zn-based coatings with a coating weight of less than 400 g / m 2 are applied to the respective flat steel product, then flux baths having a density of> 1.35-1.45 g / cm 3 have proved favorable.
Zur besonderen Wirksamkeit des erfindungsgemäß eingesetzten Flussmittels trägt es darüber hinaus bei, wenn sein pH-Wert 4 - 4,5 beträgt. Wird die für den pH-Wert des Fluxmediums angegebene Obergrenze überschritten, ist das Medium zu wässrig und der Feinstreinigungseffekt der Stahloberfläche zu gering. Wird die für den pH-Wert des Fluxmediums angegebene Untergrenze unterschritten, ist das Fluxen wiederum zu scharf und die Korngrenzen an der Stahloberfläche können zu stark angegriffen werden.In addition, it contributes to the particular effectiveness of the flux used according to the invention when its pH is 4 to 4.5. If the upper limit specified for the pH of the flux medium is exceeded, the medium is too watery and the ultrafine cleaning effect of the steel surface is too low. If the lower limit specified for the pH of the flux medium is exceeded, the fluxing is again too sharp and the grain boundaries on the steel surface can be attacked too strongly.
Im Arbeitsschritt e) wird das aus dem Flussmittelbad austretende Stahlflachprodukt getrocknet und auf die Eintrittstemperatur gebracht, mit der es in das anschließend durchlaufene Schmelzenbad eintritt. Die Mindesttemperatur sollte dabei so hoch sein, dass das auf der Stahlflachprodukt-Oberfläche aus dem Flussmittelbad mitgeführte Fluxmedium ausreichend angetrocknet wird, um Benetzungsstörungen bei der Beschichtung im Schmelzenbad zu vermeiden. Gleichzeitig sollte die Trocknungstemperatur jedoch nicht zu hoch sein, um ein Abbrennen des Fluxmediums zu vermeiden. Als besonders geeigneter Temperaturbereich für die Trocknung hat es sich deshalb erwiesen, wenn das Stahlflachprodukt auf eine Temperatur von 100 - 230 °C erwärmt wird. Die Bandeintrittstemperatur sollte während des Trocknens für mindestens 10 s gehalten werden, um das Stahlflachprodukt adäquat durchzuwärmen. Die maximal zulässige Trocknungsdauer hängt von der Leistungsfähigkeit der jeweils eingesetzten Trocknungsanlage ab. Praktische Versuche haben hier belegt, dass bei den in der heutigen Praxis eingesetzten Anlagen eine Höchstdauer von 30 s sinnvoll ist.In step e), the steel flat product emerging from the flux bath is dried and brought to the inlet temperature, with which it enters the subsequently passed melt bath. The minimum temperature should be so high that the flux medium entrained on the flat steel product surface from the flux bath is sufficiently dried to avoid wetting disturbances during the coating in the melt bath. At the same time, however, the drying temperature should not be too high to avoid burning off the flux medium. As a particularly suitable temperature range for drying, it has therefore been found that the flat steel product is heated to a temperature of 100 - 230 ° C. The belt inlet temperature should be held during drying for at least 10 seconds to adequately heat the flat steel product. The maximum permissible drying time depends on the performance of the particular drying plant used. Practical experiments have shown that a maximum of 30 s is useful for the systems used in today's practice.
Im Arbeitsschritt f) durchläuft das Stahlflachprodukt das Schmelzenbad. Optimale Beschichtungsergebnisse ergeben sich dabei dann, wenn die Verweildauer, über die der jeweilige Abschnitt des Stahlflachprodukts dem Schmelzenbad ausgesetzt ist, 1 - 120 s, insbesondere 1 - 60 s, beträgt. Dabei können über eine entsprechend eingestellte Legierung des Schmelzenbads Zn- oder Al-Überzüge auf dem jeweiligen Stahlflachprodukt erzeugt werden. Zu den Zn- oder Al-basierten Überzügen zählen dabei:
- Z-Überzüge, die basierend auf einem Schmelzenbad erzeugt werden, das neben Zn und herstellungs- und prozessbedingt unvermeidbaren Verunreinigungen Al in Gehalten von mehr als 0,10 Gew.-%
und bis zu 0,3 Gew.-%, Si in Gehaltenvon bis zu 0,2 Gew.-% und Fe in Gehalten von wenigerals 0,5 Gew.-% enthält, - ZA-Überzüge, die basierend auf einem Schmelzenbad erzeugt werden, das neben Zn und herstellungs- und prozessbedingt unvermeidbaren Verunreinigungen Al in Gehalten von mehr als 0,10 Gew.-%
und bis zu 5 Gew.-%, Si in Gehaltenvon bis zu 0,2 Gew.-% und Fe in Gehalten von wenigerals 0,5 Gew.-% enthält, - ZM-Überzüge, die basierend auf einem Schmelzenbad erzeugt werden, das neben Zn und herstellungs- und prozessbedingt unvermeidbaren Verunreinigungen Al in Gehalten von mehr als 0,10 Gew.-% und bis zu 8,0 Gew.-%, Mg in Gehalten von 0,2 - 8,0 Gew.-%, Si in Gehalten von weniger als 2,0 Gew.-%, Pb in Gehalten von weniger als 0,1 Gew.-%, Ti in Gehalten von weniger als 0,2 Gew.-%, Ni in Gehalten von weniger als 1 Gew.-%, Cu in Gehalten von weniger als 1 Gew.-%, Co in Gehalten von weniger als 0,3 Gew.-%, Mn in Gehalten von weniger als 0,05 Gew.-%, Cr in Gehalten von weniger als 0,1 Gew.-%, Sr in Gehalten von weniger als 0,5 Gew.-%, B in Gehalten von weniger als 0,1 Gew.-%, Bi in Gehalten von weniger als 0,1 Gew.-%, Cd in Gehalten von weniger als 0,1 Gew.-% und Fe in Gehalten von weniger als 3,0 Gew.-% enthält, wobei für das Verhältnis %Al/%Mg des Al-Gehalts %Al zum Mg-Gehalt %Mg gilt %Al/%Mg ≤ 1,
- ZF-Überzüge, die basierend auf einem Schmelzenbad erzeugt werden, das neben Zn und herstellungs- und prozessbedingt unvermeidbaren Verunreinigungen Al in Gehalten von mehr als 0,1 Gew.-% und bis zu 0,15 Gew.-%, Si in Gehalten
von bis zu 0,2 Gew.-% und Fe in Gehalten von wenigerals 0,5 Gew.-% enthält,
sowie - AS-Überzüge, die basierend auf einem Schmelzenbad erzeugt werden, das neben Al und herstellungs- und prozessbedingt unvermeidbaren Verunreinigungen Si in Gehalten von 1 - 15 Gew.-% und Fe in Gehalten von 1,0 - 5,0 Gew.-% enthält.
- Z coatings, which are produced on the basis of a melt bath, which in addition to Zn and production- and process-related unavoidable impurities Al in contents of more than 0.10 wt .-% and up to 0.3 wt .-%, Si in levels of contains up to 0.2% by weight and Fe in contents of less than 0.5% by weight,
- ZA coatings, which are produced on the basis of a melt bath, which in addition to Zn and production and process inevitable impurities Al in contents of more than 0.10 wt .-% and up to 5 wt .-%, Si in amounts of up to Contains 0.2% by weight and Fe in contents of less than 0.5% by weight,
- ZM coatings, which are produced based on a melt bath, which in addition to Zn and production and process inevitable impurities Al in levels of more than 0.10 wt .-% and up to 8.0 wt .-%, Mg in levels of 0.2 to 8.0 wt.%, Si in contents of less than 2.0 wt.%, Pb in contents of less than 0.1 wt.%, Ti in contents of less than 0.2 wt %, Ni in contents of less than 1% by weight, Cu in contents of less than 1% by weight, Co in contents of less than 0.3% by weight, Mn in contents of less than 0, 05 wt%, Cr in contents of less than 0.1 wt%, Sr in contents of less than 0.5 wt%, B in contents of less than 0.1 wt%, Bi in Contents of less than 0.1% by weight, Cd in contents of less than 0.1% by weight and Fe in contents of less than 3.0% by weight, wherein for the ratio% Al /% Mg of Al content% Al to Mg content% Mg,% Al /% Mg ≦ 1,
- ZF coatings, which are produced on the basis of a melt bath, which in addition to Zn and production and process inevitable impurities Al in contents of more than 0.1 wt .-% and up to 0.15 wt .-%, Si in levels of contains up to 0.2% by weight and Fe in contents of less than 0.5% by weight,
such as - AS coatings produced based on a molten bath containing Si in amounts of 1-15% by weight and Fe in contents of 1.0-5.0% by weight, in addition to Al and manufacturing-unavoidable impurities ,
Versuche haben belegt, dass Stahlflachprodukte, die aus unter die oben genannte Legierungsvorschrift fallenden rostfreien CrNi-Stählen gefertigt und in erfindungsgemäßer Weise prozessiert worden sind, sich mit jedem der voranstehend erläuterten Überzüge beschichten lassen und dass sich aus einem Baustahl der oben angegebenen Art gefertigte Stahlflachprodukte besonders gut mit einem in erfindungsgemäßer Weise aufgebrachten ZM-Überzug gegen Korrosion schützen lassen. Stahlflachprodukte, die aus nicht rostendem Stahl hergestellt und in erfindungsgemäßer Weise mit einem AS-Überzug versehen sind, eignen sich insbesondere bei Hochtemperaturanwendungen. Durch die AS-Beschichtung werden solche Stahlflachprodukte gegen die Bildung von Anlauffarben geschützt.Tests have shown that flat steel products made of stainless CrNi steels covered by the abovementioned alloying instruction and processed in accordance with the invention can be coated with any of the above-described coatings, and particularly flat steel products made of a structural steel of the type specified above can be well protected with a coated in accordance with the invention ZM coating against corrosion. Flat steel products, which are made of stainless steel and provided in accordance with the invention with an AS coating, are particularly suitable for high temperature applications. The AS coating protects such flat steel products against the formation of tarnish.
Im Fall, dass es sich bei dem Schmelzenbad um ein Znbasiertes Bad handelt, beträgt die Schmelzenbadtemperatur 430 - 700 °C, typischerweise 430 - 530 °C, während bei einem Schmelzenbad, das Al-basiert ist, die Badtemperatur typischerweise bis zu 780 °C, insbesondere 650 - 780 °C, beträgt.In the case where the melt bath is a Zn-based bath, the melt bath temperature is 430-700 ° C, typically 430-530 ° C, while at a melt bath which is Al-based, the bath temperature typically up to 780 ° C, in particular 650-780 ° C, is.
Soll das schmelztauchbeschichtete Stahlflachprodukt in-line thermisch nachbehandelt werden (Galvannealing), um einen Fe-Zn-Legierungsüberzug zu erzeugen, so hat es sich bewährt, wenn das Schmelzenbad so eingestellt wird, dass auf dem Stahlsubstrat ein ZF-Überzug erzeugt wird.If the hot dip coated flat steel product is to be thermally aftertreated (galvannealed) in-line to produce an Fe-Zn alloy coating, it has been found useful to adjust the melt bath to form an ZF coating on the steel substrate.
Ebenso optional wie die Galvannealing-Behandlung kann das erhaltene schmelztauchbeschichtete Stahlflachprodukt einer Passivierung durch eine entsprechende chemische Behandlung oder einem Nachwalzen unterzogen werden, um eine Maßhaltigkeit und seine mechanischen Eigenschaften zu verbessern.As optional as the galvannealing treatment, the resulting hot dip coated steel flat product may be subjected to passivation by a corresponding chemical treatment or temper rolling to improve dimensional stability and its mechanical properties.
Nachfolgend wird die Erfindung anhand von Ausführungsbeispielen näher erläutert. Es zeigen:
- Fig. 1
- eine Anlage zum Schmelztauchbeschichten mit den für die Durchführung des erfindungsgemäßen Verfahrens erforderlichen und optional zusätzlich vorgesehenen Arbeitsstationen;
- Fig. 2
- eine Querschliffdarstellung eines Stahlflachprodukts mit in erfindungsgemäßer Weise auf ein Stahlflachprodukt appliziertem ZM-Überzug;
- Fig. 3
- eine Querschliffdarstellung eines Stahlflachprodukts mit in erfindungsgemäßer Weise auf ein Stahlflachprodukt appliziertem AS-Überzug;
- Fig. 4
- eine Querschliffdarstellung eines Stahlflachprodukts mit in erfindungsgemäßer Weise auf ein Stahlflachprodukt appliziertem ZM-Überzug.
- Fig. 1
- a system for hot dip coating with the required for carrying out the method according to the invention and optionally additionally provided workstations;
- Fig. 2
- a cross-sectional view of a flat steel product with applied in accordance with the invention on a flat steel product ZM coating;
- Fig. 3
- a cross-sectional view of a flat steel product with in inventive Manner on a flat steel product applied AS coating;
- Fig. 4
- a cross-sectional view of a flat steel product with applied in accordance with the invention on a flat steel ZM coating.
Die Anlage 1 zum Schmelztauchbeschichten eines als warmgewalztes und zu einem Coil C gewickeltes Band bereitgestellten Stahlflachprodukts P umfasst in einer in Förderrichtung F in-line aufeinander folgenden Aufstellung eine Abhaspelstation 2, eine Beizstation 3, eine Spülstation 4, eine Flux-Station 5, eine Trocknungsstation 6, eine Schmelztauchstation 7 und eine Kühlstation 8 und eine Aufhaspelstation 9.The plant 1 for the hot dip coating of a flat rolled product P provided as a hot rolled coil and a coil C comprises, in a successive line-up in the conveying direction F, an uncoiling
In der Abhaspelstation 2 wird das zu beschichtende Stahlflachprodukt P vom jeweiligen Coil C abgewickelt und durchläuft zunächst die Beizstation 3 und darauffolgend die Spülstation 4, bevor es in die Flux-Station 5 gelangt. Das aus der Flux-Station 5 austretende Stahlflachprodukt P durchläuft die Trocknungsstation 6 und wird dann in das Schmelzenbad S der Schmelztauchstation 7 geleitet. Das aus dem Schmelzbad S austretende Stahlflachprodukt P durchläuft anschließend die Kühlstation 8, in der es auf Raumtemperatur abgekühlt wird, bevor es in der Aufhaspelstation 9 wieder zu einem Coil gewickelt wird.In the
In der Beschichtungsanlage 1 sind 55 Versuche mit als warmgewalzte Bänder angelieferten Stahlflachprodukten P durchgeführt worden, die aus unterschiedlichen Stählen W1, W2, W3, W4, W5, W6, W7 hergestellt worden sind. Die jeweilige Zusammensetzung der Stähle W1 - W7 ist in Tabelle 1 angegeben. Bei den Stählen W1 - W4 handelt es sich um konventionelle Baustähle, während die Stähle W5 - W7 konventionelle nicht rostende CrNi-Edelstähle sind.In the coating installation 1, 55 trials have been carried out with flat-rolled steel products P supplied as hot-rolled strips, which have been produced from different steels W1, W2, W3, W4, W5, W6, W7. The respective composition of the steels W1 - W7 is given in Table 1. The steels W1 - W4 are conventional structural steels, while the steels W5 - W7 are conventional stainless CrNi stainless steels.
Die jeweils verarbeiteten Stahlflachprodukte P haben in der Beizstation 3 ein konventionelles auf Salzsäure (basierendes Beizmittelbad B durchlaufen, das auf eine Temperatur TB erwärmt worden ist und das vom jeweiligen Abschnitt des jeweiligen Stahlflachprodukts P innerhalb einer Beizdauer tB passiert worden ist.The respectively processed flat steel products P have undergone a conventional hydrochloric acid-based pickling bath B in the
Anschließend haben die Stahlflachprodukte P in der Spüleinrichtung 4 ein aus vollentsalztem Wasser bestehendes Spülbad V durchlaufen, das auf eine Temperatur TS erwärmt worden ist und das vom jeweiligen Abschnitt des jeweiligen Stahlflachprodukts P innerhalb einer Spüldauer tS absolviert worden ist.Subsequently, the flat steel products P in the rinsing device 4 have passed through a rinsing bath V consisting of demineralized water, which has been heated to a temperature TS and has been discharged from the respective section of the respective flat steel product P within a rinsing time tS.
Daraufhin sind die Stahlflachprodukte P in der Flux-Station 5 durch ein Flussmittelbad X geleitet worden, das vom jeweiligen Abschnitt des jeweiligen Stahlflachprodukts P innerhalb einer Dauer tF durchlaufen worden ist und eine Temperatur TF, einen pH-Wert pH_F und eine Dichte r-F hatte. Dabei sind bei den Versuchen zwölf unterschiedlich zusammengesetzte Flussmittelbäder X eingesetzt worden. Die zwölf Zusammensetzungen X1 - X12 der Flussmittelbäder X sind in Tabelle 2 angegeben.Thereafter, the flat steel products P in the
In der Trocknungsstation 6 sind die Stahlflachprodukte getrocknet und auf die jeweilige Badeintrittstemperatur TE gebracht worden.In the drying
Anschließend haben die Stahlflachprodukte P in der Schmelztauchstation 7 das jeweilige Schmelzenbad S durchlaufen, das auf einer Temperatur TBad gehalten worden ist.Subsequently, the flat steel products P in the hot-
Beim Austritt aus der Schmelztauchstation 7 ist bei den Stahlflachprodukten die Dicke des jeweils aufgebrachten Schmelztauchüberzugs in an sich bekannter Weise mittels einer hier nicht gezeigten Abstreifeinrichtung eingestellt worden.When leaving the hot-
In den Tabellen 3a,3b sind für insgesamt 55 Versuche die jeweils eingestellten Betriebsparameter zusammengefasst. Tabelle 3a enthält dabei die erfindungsgemäß durchgeführten Versuche, die ein gutes, fehlerfreies Beschichtungsergebnis erbracht haben, während in den Tabellen 3b,3c die Versuche zusammengefasst sind, die fehlerhafte Beschichtungsergebnisse ergeben haben.In Tables 3a, 3b, the respectively set operating parameters are summarized for a total of 55 tests. Table 3a contains the experiments carried out according to the invention, which have provided a good, error-free coating result, while in the tables 3b, 3c, the experiments are summarized that have resulted in incorrect coating results.
Für jeden der 55 Versuche sind dabei der jeweilige Stahl W1 - W7, aus dem das jeweils verarbeitete Stahlflachprodukt P bestand, die jeweilige Temperatur TB des Beizmittels, die Beizdauer tB, die Temperatur TS des Spülmittels und die Spülzeit tS, das in der Flux-Station 5 jeweils durchlaufene Flussmittelbad X1 - X12, die Dauer tF, in der das jeweilige Stahlflachprodukt das jeweilige Flussmittelbad X1 - X12 durchlaufen hat, die jeweilige Flussmittelbad-Temperatur TF, der jeweilige pH-Wert pH_F und die jeweilige Dichte r-F des jeweiligen Flussmittelbads X1 - X12, die jeweilige Trocknungs- bzw. Badeintrittstemperatur TE, die Zusammensetzung des jeweiligen Schmelzenbads S, die Temperatur TBad des jeweiligen Schmelzenbads S und das jeweils auf einer der beschichteten Seiten des Stahlflachprodukts P erreichte Auflagengewicht AG angegeben. Die Verweildauer in der Trocknungsstation betrug jeweils 20 s und die im Schmelzenbad jeweils 10 s.For each of the 55 tests are the respective steel W1 - W7, which consisted of each processed flat steel product P, the respective temperature TB of the mordant, the pickling time tB, the temperature TS of the detergent and the purge time tS in the
Die in
Die in
Die in
Ein Vergleich der
Beim in
Claims (16)
beträgt;
is;
dadurch gekennzeichnet, dass die Verweildauer des Stahlflachprodukts in dem Schmelzenbad 1 - 120 s beträgt.Method according to one of the preceding claims,
characterized in that the residence time of the flat steel product in the melt bath is 1 - 120 s.
dadurch gekennzeichnet, dass die Temperatur des Schmelzenbads 430 - 780 °C beträgt.Method according to one of the preceding claims,
characterized in that the temperature of the melt bath is 430 - 780 ° C.
dadurch gekennzeichnet, dass das Stahlflachprodukt höchstens 600 mm breit ist.Method according to one of the preceding claims,
characterized in that the flat steel product is at most 600 mm wide.
dadurch gekennzeichnet, dass das Schmelzenbad ein Z-, ZA-, ZM-, ZF- oder AS-Schmelzenbad ist.Method according to one of the preceding claims,
characterized in that the melt bath is a Z, ZA, ZM, ZF or AS melt bath.
C: 0,001- 0,7 %,
Mn: 0,10 - 2, 0 %,
A1: 0,01 - 2,0 %,
sowie jeweils optional eines oder mehrere Elemente aus der Gruppe "Si, P, S, Cr, Cu, Mo, N, Ni, Nb, Ti, V, Zr, B" mit der Maßgabe enthält, dass für die Gehalte an den optional zugegebenen Elementen gilt:
C: 0.001-0.7%,
Mn: 0.10-2.0%,
A1: 0.01-2.0%,
and in each case optionally one or more elements from the group "Si, P, S, Cr, Cu, Mo, N, Ni, Nb, Ti, V, Zr, B" with the proviso that for the contents of the optionally added Elements applies:
C: 0,001- 0,5 %,
Mn: 0,10 - 6,0 %,
Al : 0,01 - 2,0 %,
Cr: 5,0 - 30,0 %,
Ni: 2,00 - 30,0 %
sowie jeweils optional eines oder mehrere Elemente aus der Gruppe "Si, Cu, Mo, N, Nb, Ti, V" mit der Maßgabe enthält, dass für die Gehalte an den optional zugegebenen Elementen gilt:
C: 0.001-0.5%,
Mn: 0.10 - 6.0%,
Al: 0.01-2.0%,
Cr: 5.0-30.0%,
Ni: 2.00 - 30.0%
and in each case optionally one or more elements from the group "Si, Cu, Mo, N, Nb, Ti, V" with the proviso that the following applies to the contents of the optionally added elements:
dadurch gekennzeichnet, dass der metallische Überzug ein Z-Überzug ist.Flat steel product according to claim 10 or 11,
characterized in that the metallic coating is a Z-coating.
dadurch gekennzeichnet, dass der metallische Überzug ein ZA-Überzug ist.Flat steel product according to claim 10 or 11,
characterized in that the metallic coating is a ZA coating.
dadurch gekennzeichnet, dass der metallische Überzug ein ZM-Überzug ist.Flat steel product according to claim 10 or 11,
characterized in that the metallic coating is a ZM coating.
dadurch gekennzeichnet, dass der metallische Überzug ein ZF-Überzug ist.Flat steel product according to claim 10 or 11,
characterized in that the metallic coating is an IF coating.
dadurch gekennzeichnet, dass der metallische Überzug ein AS-Überzug ist.Flat steel product according to claim 10 or 11,
characterized in that the metallic coating is an AS coating.
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP13174979.8A EP2821520B1 (en) | 2013-07-03 | 2013-07-03 | Method for the coating of steel flat products with a metallic protective layer |
ES13174979T ES2851199T3 (en) | 2013-07-03 | 2013-07-03 | Procedure for coating flat steel products with a metallic protective layer |
PCT/EP2014/062879 WO2015000707A1 (en) | 2013-07-03 | 2014-06-18 | Method for coating flat steel products with a metallic protective layer, and flat steel products coated with a metallic protective layer |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP13174979.8A EP2821520B1 (en) | 2013-07-03 | 2013-07-03 | Method for the coating of steel flat products with a metallic protective layer |
Publications (2)
Publication Number | Publication Date |
---|---|
EP2821520A1 true EP2821520A1 (en) | 2015-01-07 |
EP2821520B1 EP2821520B1 (en) | 2020-11-11 |
Family
ID=48740943
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP13174979.8A Active EP2821520B1 (en) | 2013-07-03 | 2013-07-03 | Method for the coating of steel flat products with a metallic protective layer |
Country Status (3)
Country | Link |
---|---|
EP (1) | EP2821520B1 (en) |
ES (1) | ES2851199T3 (en) |
WO (1) | WO2015000707A1 (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN112522591A (en) * | 2019-09-19 | 2021-03-19 | 宝山钢铁股份有限公司 | Method for producing high-strength and high-corrosion-resistance steel by thin-strip continuous casting |
US11473174B2 (en) * | 2017-01-16 | 2022-10-18 | Nippon Steel Corporation | Coated steel product |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP7252922B2 (en) * | 2019-08-19 | 2023-04-05 | Jfeスチール株式会社 | Flux solution for hot-dip galvanizing and method for manufacturing hot-dip galvanized steel pipe |
Citations (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0012301A1 (en) * | 1978-12-06 | 1980-06-25 | BASF Aktiengesellschaft | Flux for dry galvanization |
US4496612A (en) * | 1982-04-06 | 1985-01-29 | E. I. Du Pont De Nemours And Company | Aqueous flux for hot dip metalizing process |
DE3814372A1 (en) * | 1988-04-28 | 1989-11-09 | Deca Chemie Gmbh | Process for the economical operation of a hot-metallising plant |
WO1995004607A1 (en) * | 1993-08-05 | 1995-02-16 | Ferro Technologies, Inc. | Lead-free galvanizing technique |
US5437738A (en) * | 1994-06-21 | 1995-08-01 | Gerenrot; Yum | Fluxes for lead-free galvanizing |
DE10107936A1 (en) * | 2001-02-20 | 2002-09-05 | Feuerverzinkung Hannover Gmbh | Working up process liquids in a hot galvanizing installation comprises feeding the diluate from an electrodialysis unit through a re-conditioning device to remove zinc, feeding the regenerate back to the electrodialysis unit |
EP1693477A1 (en) | 2005-02-22 | 2006-08-23 | ThyssenKrupp Steel AG | Coated steel plate |
EP1857566A1 (en) | 2006-05-15 | 2007-11-21 | ThyssenKrupp Steel AG | Flat steel product provided with a corrosion protection coating and method of its manufacture |
WO2009030823A1 (en) | 2007-09-03 | 2009-03-12 | Siemens Vai Metals Technologies Sas | Controlled method and device for oxidation/reduction of the surface of a steel strip running continuously through a radiant tube oven for galvanisation thereof |
EP2055799A1 (en) | 2007-11-05 | 2009-05-06 | ThyssenKrupp Steel AG | Flat steel product with an anti-corrosion metal coating and method for creating an anti-corrosion metal coating on a flat steel product |
Family Cites Families (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
IT1294228B1 (en) * | 1997-08-01 | 1999-03-24 | Acciai Speciali Terni Spa | PROCEDURE FOR THE PRODUCTION OF AUSTENITIC STAINLESS STEEL BELTS, AUSTENITIC STAINLESS STEEL BELTS SO |
ITRM20010678A1 (en) * | 2001-11-15 | 2003-05-15 | Acciai Speciali Terni Spa | PROCEDURE FOR THE ONLINE RECRYSTALLIZATION OF RAW SOLIDIFICATION TAPES IN CARBON STEEL AND IN ALLOY AND BONDED STEEL |
EP1396550A1 (en) * | 2002-08-28 | 2004-03-10 | ThyssenKrupp Stahl AG | Method for manufacturing hot strip |
JP5842515B2 (en) * | 2011-09-29 | 2016-01-13 | Jfeスチール株式会社 | Hot-rolled steel sheet and manufacturing method thereof |
DE102012101018B3 (en) * | 2012-02-08 | 2013-03-14 | Thyssenkrupp Nirosta Gmbh | Process for hot dip coating a flat steel product |
-
2013
- 2013-07-03 EP EP13174979.8A patent/EP2821520B1/en active Active
- 2013-07-03 ES ES13174979T patent/ES2851199T3/en active Active
-
2014
- 2014-06-18 WO PCT/EP2014/062879 patent/WO2015000707A1/en active Application Filing
Patent Citations (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0012301A1 (en) * | 1978-12-06 | 1980-06-25 | BASF Aktiengesellschaft | Flux for dry galvanization |
US4496612A (en) * | 1982-04-06 | 1985-01-29 | E. I. Du Pont De Nemours And Company | Aqueous flux for hot dip metalizing process |
DE3814372A1 (en) * | 1988-04-28 | 1989-11-09 | Deca Chemie Gmbh | Process for the economical operation of a hot-metallising plant |
WO1995004607A1 (en) * | 1993-08-05 | 1995-02-16 | Ferro Technologies, Inc. | Lead-free galvanizing technique |
US5437738A (en) * | 1994-06-21 | 1995-08-01 | Gerenrot; Yum | Fluxes for lead-free galvanizing |
DE10107936A1 (en) * | 2001-02-20 | 2002-09-05 | Feuerverzinkung Hannover Gmbh | Working up process liquids in a hot galvanizing installation comprises feeding the diluate from an electrodialysis unit through a re-conditioning device to remove zinc, feeding the regenerate back to the electrodialysis unit |
EP1693477A1 (en) | 2005-02-22 | 2006-08-23 | ThyssenKrupp Steel AG | Coated steel plate |
EP1857566A1 (en) | 2006-05-15 | 2007-11-21 | ThyssenKrupp Steel AG | Flat steel product provided with a corrosion protection coating and method of its manufacture |
WO2009030823A1 (en) | 2007-09-03 | 2009-03-12 | Siemens Vai Metals Technologies Sas | Controlled method and device for oxidation/reduction of the surface of a steel strip running continuously through a radiant tube oven for galvanisation thereof |
EP2055799A1 (en) | 2007-11-05 | 2009-05-06 | ThyssenKrupp Steel AG | Flat steel product with an anti-corrosion metal coating and method for creating an anti-corrosion metal coating on a flat steel product |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US11473174B2 (en) * | 2017-01-16 | 2022-10-18 | Nippon Steel Corporation | Coated steel product |
CN112522591A (en) * | 2019-09-19 | 2021-03-19 | 宝山钢铁股份有限公司 | Method for producing high-strength and high-corrosion-resistance steel by thin-strip continuous casting |
CN112522591B (en) * | 2019-09-19 | 2022-03-18 | 宝山钢铁股份有限公司 | Method for producing high-strength and high-corrosion-resistance steel by thin-strip continuous casting |
Also Published As
Publication number | Publication date |
---|---|
EP2821520B1 (en) | 2020-11-11 |
ES2851199T3 (en) | 2021-09-03 |
WO2015000707A1 (en) | 2015-01-08 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
EP2235229B9 (en) | Method for coating a warm or cold-rolled flat steel product comprising 6 - 30 weight-% mn with a metallic protective layer | |
EP2848709B1 (en) | Method for producing a steel component with an anti-corrosive metal coating and steel component | |
EP3169734B1 (en) | Steel product with an anticorrosive coating of aluminium alloy and method for the production thereof | |
DE3201475C2 (en) | ||
EP2393953B1 (en) | Method for producing a coated steel component by means of hot forming and steel component produced by means of hot forming | |
EP2683843B1 (en) | Flat steel product and method for producing a flat steel product | |
DE102006039307B3 (en) | Process for coating a 6-30 wt.% Mn-containing hot or cold rolled steel strip with a metallic protective layer | |
EP2010690B1 (en) | Hot dip coating process for a steel plate product made of high strengthheavy-duty steel | |
EP2848715B1 (en) | Method for producing a steel component with an anti-corrosive metal coating | |
EP2290133A1 (en) | Method for producing a steel component with an anti-corrosive metal coating and steel component | |
DE102012101018B3 (en) | Process for hot dip coating a flat steel product | |
EP2055799A1 (en) | Flat steel product with an anti-corrosion metal coating and method for creating an anti-corrosion metal coating on a flat steel product | |
EP2513346B1 (en) | Method for producing an easily deformable flat steel product | |
DE69106552T2 (en) | Surface-treated steel strip with improved weldability and coating properties and its manufacture. | |
EP3880860B1 (en) | Method for the zinc plating, in particular galvanising, of iron and steel products | |
EP2821520B1 (en) | Method for the coating of steel flat products with a metallic protective layer | |
EP3363576B1 (en) | Method and system for identification and/or marking of hot-dip galvanized components and components manufactured with them | |
EP3872230A1 (en) | Method for producing hardened steel components with a conditioned zinc alloy corrosion protection layer | |
DE102013107011A1 (en) | Process for coating long Cu products with a metallic protective layer and a Cu long product provided with a metallic protective layer | |
DE19926102B4 (en) | Process and plant for producing an electrolytically coated hot strip | |
EP1350865A2 (en) | Tinned and phosphatised sheet and method for producing such a sheet | |
EP4110972B1 (en) | Method for producing hardened steel components with a conditioned zinc alloy corrosion protection layer | |
JP3294322B2 (en) | Method for producing hot-dip galvanized steel sheet for deep drawing with excellent paint bake hardenability and corrosion resistance | |
EP3872231A1 (en) | Method for conditioning the surface of a metal strip coated with a zinc alloy corrosion protection layer | |
DE102024104377A1 (en) | Sheet metal part with improved cathodic corrosion protection |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
17P | Request for examination filed |
Effective date: 20130703 |
|
AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR |
|
AX | Request for extension of the european patent |
Extension state: BA ME |
|
R17P | Request for examination filed (corrected) |
Effective date: 20150703 |
|
RBV | Designated contracting states (corrected) |
Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR |
|
17Q | First examination report despatched |
Effective date: 20151109 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: EXAMINATION IS IN PROGRESS |
|
GRAP | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOSNIGR1 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: GRANT OF PATENT IS INTENDED |
|
INTG | Intention to grant announced |
Effective date: 20200604 |
|
GRAS | Grant fee paid |
Free format text: ORIGINAL CODE: EPIDOSNIGR3 |
|
GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE PATENT HAS BEEN GRANTED |
|
AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR |
|
REG | Reference to a national code |
Ref country code: GB Ref legal event code: FG4D Free format text: NOT ENGLISH |
|
REG | Reference to a national code |
Ref country code: CH Ref legal event code: EP |
|
REG | Reference to a national code |
Ref country code: AT Ref legal event code: REF Ref document number: 1333550 Country of ref document: AT Kind code of ref document: T Effective date: 20201115 |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R096 Ref document number: 502013015281 Country of ref document: DE |
|
REG | Reference to a national code |
Ref country code: IE Ref legal event code: FG4D Free format text: LANGUAGE OF EP DOCUMENT: GERMAN |
|
REG | Reference to a national code |
Ref country code: SE Ref legal event code: TRGR |
|
REG | Reference to a national code |
Ref country code: GB Ref legal event code: 732E Free format text: REGISTERED BETWEEN 20210218 AND 20210224 |
|
RAP2 | Party data changed (patent owner data changed or rights of a patent transferred) |
Owner name: THYSSENKRUPP STEEL EUROPE AG Owner name: OUTOKUMPU NIROSTA GMBH |
|
REG | Reference to a national code |
Ref country code: SK Ref legal event code: T3 Ref document number: E 36507 Country of ref document: SK |
|
REG | Reference to a national code |
Ref country code: NL Ref legal event code: MP Effective date: 20201111 |
|
REG | Reference to a national code |
Ref country code: AT Ref legal event code: PC Ref document number: 1333550 Country of ref document: AT Kind code of ref document: T Owner name: OUTOKUMPU NIROSTA GMBH, DE Effective date: 20210215 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: FI Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20201111 Ref country code: RS Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20201111 Ref country code: NO Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210211 Ref country code: PT Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210311 Ref country code: GR Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210212 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: LV Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20201111 Ref country code: IS Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210311 Ref country code: PL Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20201111 Ref country code: BG Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210211 |
|
REG | Reference to a national code |
Ref country code: LT Ref legal event code: MG9D |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: HR Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20201111 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: RO Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20201111 Ref country code: LT Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20201111 Ref country code: EE Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20201111 Ref country code: SM Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20201111 |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R097 Ref document number: 502013015281 Country of ref document: DE |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: DK Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20201111 |
|
REG | Reference to a national code |
Ref country code: ES Ref legal event code: FG2A Ref document number: 2851199 Country of ref document: ES Kind code of ref document: T3 Effective date: 20210903 |
|
PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |
|
26N | No opposition filed |
Effective date: 20210812 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: AL Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20201111 Ref country code: NL Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20201111 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: SI Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20201111 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: CZ Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20210703 |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R119 Ref document number: 502013015281 Country of ref document: DE |
|
REG | Reference to a national code |
Ref country code: CH Ref legal event code: PL |
|
GBPC | Gb: european patent ceased through non-payment of renewal fee |
Effective date: 20210703 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: MC Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20201111 |
|
REG | Reference to a national code |
Ref country code: BE Ref legal event code: MM Effective date: 20210731 |
|
REG | Reference to a national code |
Ref country code: SK Ref legal event code: PC4A Ref document number: 28966 Country of ref document: SK Owner name: TILLOTTS PHARMA AG, RHEINFELDEN, CH Free format text: FORMER OWNER: ASTELLAS PHARMA EUROPE LTD., SURREY, GB Effective date: 20220322 Ref country code: SK Ref legal event code: PC4A Ref document number: 29766 Country of ref document: SK Owner name: TILLOTTS PHARMA AG, RHEINFELDEN, CH Free format text: FORMER OWNER: ASTELLAS PHARMA EUROPE LTD., SURREY, GB Effective date: 20220322 Ref country code: SK Ref legal event code: PC4A Ref document number: 22156 Country of ref document: SK Owner name: R-PHARM INTERNATIONAL, LLC, MOSCOW, RU Free format text: FORMER OWNER: UCB PHARMA S.A., BRUSSELS, BE Effective date: 20220325 Ref country code: SK Ref legal event code: PC4A Ref document number: 15733 Country of ref document: SK Owner name: TROY TECHNOLOGY II, INC., FLORHAM PARK, NJ, US Free format text: FORMER OWNER: TROY TECHNOLOGY CORPORATION, INC., WILMINGTON, DE; US Effective date: 20220317 Ref country code: SK Ref legal event code: PC4A Ref document number: 17514 Country of ref document: SK Owner name: R-PHARM INTERNATIONAL, LLC, MOSCOW, RU Free format text: FORMER OWNER: UCB PHARMA S.A., BRUXELLES, BE Effective date: 20220323 Ref country code: SK Ref legal event code: MM4A Ref document number: E 36507 Country of ref document: SK Effective date: 20210703 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: LI Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20210731 Ref country code: GB Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20210703 Ref country code: DE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20220201 Ref country code: CH Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20210731 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: IS Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20210311 Ref country code: SK Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20210703 Ref country code: SE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20210704 Ref country code: LU Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20210703 Ref country code: FR Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20210731 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: IE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20210703 Ref country code: BE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20210731 |
|
REG | Reference to a national code |
Ref country code: AT Ref legal event code: MM01 Ref document number: 1333550 Country of ref document: AT Kind code of ref document: T Effective date: 20210703 |
|
REG | Reference to a national code |
Ref country code: ES Ref legal event code: FD2A Effective date: 20220929 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: ES Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20210704 Ref country code: AT Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20210703 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: IT Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20210703 Ref country code: HU Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT; INVALID AB INITIO Effective date: 20130703 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: CY Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20201111 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: MK Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20201111 |