EP0596273B1 - Product for pickling surfaces of chromium-nickel steel or chromium steel and its use - Google Patents
Product for pickling surfaces of chromium-nickel steel or chromium steel and its use Download PDFInfo
- Publication number
- EP0596273B1 EP0596273B1 EP93116251A EP93116251A EP0596273B1 EP 0596273 B1 EP0596273 B1 EP 0596273B1 EP 93116251 A EP93116251 A EP 93116251A EP 93116251 A EP93116251 A EP 93116251A EP 0596273 B1 EP0596273 B1 EP 0596273B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- acid
- chromium
- weight
- pickling
- composition according
- 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.)
- Expired - Lifetime
Links
- 238000005554 pickling Methods 0.000 title claims abstract description 33
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 21
- 239000010959 steel Substances 0.000 title claims abstract description 21
- VNNRSPGTAMTISX-UHFFFAOYSA-N chromium nickel Chemical compound [Cr].[Ni] VNNRSPGTAMTISX-UHFFFAOYSA-N 0.000 title claims abstract description 9
- 229910001220 stainless steel Inorganic materials 0.000 title description 11
- KRHYYFGTRYWZRS-UHFFFAOYSA-N Fluorane Chemical compound F KRHYYFGTRYWZRS-UHFFFAOYSA-N 0.000 claims abstract description 34
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims abstract description 33
- 239000000203 mixture Substances 0.000 claims abstract description 24
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 claims abstract description 23
- 239000002253 acid Substances 0.000 claims abstract description 21
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 claims abstract description 13
- -1 Fe(III) ions Chemical class 0.000 claims abstract description 10
- 229910000147 aluminium phosphate Inorganic materials 0.000 claims abstract description 10
- 239000011651 chromium Substances 0.000 claims abstract description 10
- 229910052804 chromium Inorganic materials 0.000 claims abstract description 10
- 239000001117 sulphuric acid Substances 0.000 claims abstract description 5
- 235000011149 sulphuric acid Nutrition 0.000 claims abstract 3
- 238000000034 method Methods 0.000 claims description 12
- 150000007513 acids Chemical class 0.000 claims description 10
- RILZRCJGXSFXNE-UHFFFAOYSA-N 2-[4-(trifluoromethoxy)phenyl]ethanol Chemical compound OCCC1=CC=C(OC(F)(F)F)C=C1 RILZRCJGXSFXNE-UHFFFAOYSA-N 0.000 claims description 8
- RUTXIHLAWFEWGM-UHFFFAOYSA-H iron(3+) sulfate Chemical compound [Fe+3].[Fe+3].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O RUTXIHLAWFEWGM-UHFFFAOYSA-H 0.000 claims description 8
- 230000008569 process Effects 0.000 claims description 7
- 239000007800 oxidant agent Substances 0.000 claims description 6
- 125000004432 carbon atom Chemical group C* 0.000 claims description 4
- 150000001735 carboxylic acids Chemical class 0.000 claims description 4
- 239000002738 chelating agent Substances 0.000 claims description 4
- IIACRCGMVDHOTQ-UHFFFAOYSA-N sulfamic acid Chemical compound NS(O)(=O)=O IIACRCGMVDHOTQ-UHFFFAOYSA-N 0.000 claims description 4
- 239000004094 surface-active agent Substances 0.000 claims description 4
- 238000001311 chemical methods and process Methods 0.000 claims description 3
- QPJSUIGXIBEQAC-UHFFFAOYSA-N n-(2,4-dichloro-5-propan-2-yloxyphenyl)acetamide Chemical compound CC(C)OC1=CC(NC(C)=O)=C(Cl)C=C1Cl QPJSUIGXIBEQAC-UHFFFAOYSA-N 0.000 claims description 3
- 150000001491 aromatic compounds Chemical class 0.000 claims description 2
- 150000007522 mineralic acids Chemical class 0.000 claims description 2
- 150000007524 organic acids Chemical class 0.000 claims description 2
- 235000005985 organic acids Nutrition 0.000 claims description 2
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 abstract description 11
- 229910017604 nitric acid Inorganic materials 0.000 abstract description 11
- 239000003086 colorant Substances 0.000 abstract description 3
- 238000005494 tarnishing Methods 0.000 abstract description 3
- 238000011109 contamination Methods 0.000 abstract description 2
- 238000000576 coating method Methods 0.000 abstract 1
- 235000021110 pickles Nutrition 0.000 abstract 1
- 239000003795 chemical substances by application Substances 0.000 description 23
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 12
- 239000010935 stainless steel Substances 0.000 description 9
- 229910000360 iron(III) sulfate Inorganic materials 0.000 description 7
- KRKNYBCHXYNGOX-UHFFFAOYSA-N citric acid Chemical compound OC(=O)CC(O)(C(O)=O)CC(O)=O KRKNYBCHXYNGOX-UHFFFAOYSA-N 0.000 description 6
- 229910052759 nickel Inorganic materials 0.000 description 6
- 238000005260 corrosion Methods 0.000 description 5
- 230000007797 corrosion Effects 0.000 description 5
- 230000000694 effects Effects 0.000 description 5
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 5
- 229910052751 metal Inorganic materials 0.000 description 5
- 239000002184 metal Substances 0.000 description 5
- 239000000243 solution Substances 0.000 description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- ONMOULMPIIOVTQ-UHFFFAOYSA-N 98-47-5 Chemical compound OS(=O)(=O)C1=CC=CC([N+]([O-])=O)=C1 ONMOULMPIIOVTQ-UHFFFAOYSA-N 0.000 description 4
- 238000004140 cleaning Methods 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- POAOYUHQDCAZBD-UHFFFAOYSA-N 2-butoxyethanol Chemical compound CCCCOCCO POAOYUHQDCAZBD-UHFFFAOYSA-N 0.000 description 3
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 3
- 229910000669 Chrome steel Inorganic materials 0.000 description 3
- DBVJJBKOTRCVKF-UHFFFAOYSA-N Etidronic acid Chemical compound OP(=O)(O)C(O)(C)P(O)(O)=O DBVJJBKOTRCVKF-UHFFFAOYSA-N 0.000 description 3
- MUBZPKHOEPUJKR-UHFFFAOYSA-N Oxalic acid Chemical compound OC(=O)C(O)=O MUBZPKHOEPUJKR-UHFFFAOYSA-N 0.000 description 3
- 239000000834 fixative Substances 0.000 description 3
- 230000001590 oxidative effect Effects 0.000 description 3
- 159000000000 sodium salts Chemical class 0.000 description 3
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 2
- RGHNJXZEOKUKBD-SQOUGZDYSA-N D-gluconic acid Chemical compound OC[C@@H](O)[C@@H](O)[C@H](O)[C@@H](O)C(O)=O RGHNJXZEOKUKBD-SQOUGZDYSA-N 0.000 description 2
- VTLYFUHAOXGGBS-UHFFFAOYSA-N Fe3+ Chemical class [Fe+3] VTLYFUHAOXGGBS-UHFFFAOYSA-N 0.000 description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 2
- 125000003118 aryl group Chemical group 0.000 description 2
- TZCXTZWJZNENPQ-UHFFFAOYSA-L barium sulfate Chemical compound [Ba+2].[O-]S([O-])(=O)=O TZCXTZWJZNENPQ-UHFFFAOYSA-L 0.000 description 2
- SNCZNSNPXMPCGN-UHFFFAOYSA-N butanediamide Chemical compound NC(=O)CCC(N)=O SNCZNSNPXMPCGN-UHFFFAOYSA-N 0.000 description 2
- 239000000356 contaminant Substances 0.000 description 2
- 229910052802 copper Inorganic materials 0.000 description 2
- 239000010949 copper Substances 0.000 description 2
- 238000003912 environmental pollution Methods 0.000 description 2
- 238000007654 immersion Methods 0.000 description 2
- 239000012535 impurity Substances 0.000 description 2
- 230000002401 inhibitory effect Effects 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- BDAGIHXWWSANSR-UHFFFAOYSA-N methanoic acid Natural products OC=O BDAGIHXWWSANSR-UHFFFAOYSA-N 0.000 description 2
- 150000003839 salts Chemical class 0.000 description 2
- 239000002562 thickening agent Substances 0.000 description 2
- 231100000331 toxic Toxicity 0.000 description 2
- 230000002588 toxic effect Effects 0.000 description 2
- 239000000080 wetting agent Substances 0.000 description 2
- OSWFIVFLDKOXQC-UHFFFAOYSA-N 4-(3-methoxyphenyl)aniline Chemical compound COC1=CC=CC(C=2C=CC(N)=CC=2)=C1 OSWFIVFLDKOXQC-UHFFFAOYSA-N 0.000 description 1
- 229910002012 Aerosil® Inorganic materials 0.000 description 1
- WWZKQHOCKIZLMA-UHFFFAOYSA-N Caprylic acid Natural products CCCCCCCC(O)=O WWZKQHOCKIZLMA-UHFFFAOYSA-N 0.000 description 1
- 229910000881 Cu alloy Inorganic materials 0.000 description 1
- RGHNJXZEOKUKBD-UHFFFAOYSA-N D-gluconic acid Natural products OCC(O)C(O)C(O)C(O)C(O)=O RGHNJXZEOKUKBD-UHFFFAOYSA-N 0.000 description 1
- FEWJPZIEWOKRBE-JCYAYHJZSA-N Dextrotartaric acid Chemical compound OC(=O)[C@H](O)[C@@H](O)C(O)=O FEWJPZIEWOKRBE-JCYAYHJZSA-N 0.000 description 1
- OAKJQQAXSVQMHS-UHFFFAOYSA-N Hydrazine Chemical compound NN OAKJQQAXSVQMHS-UHFFFAOYSA-N 0.000 description 1
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 description 1
- 229910002651 NO3 Inorganic materials 0.000 description 1
- NHNBFGGVMKEFGY-UHFFFAOYSA-N Nitrate Chemical compound [O-][N+]([O-])=O NHNBFGGVMKEFGY-UHFFFAOYSA-N 0.000 description 1
- IOVCWXUNBOPUCH-UHFFFAOYSA-M Nitrite anion Chemical compound [O-]N=O IOVCWXUNBOPUCH-UHFFFAOYSA-M 0.000 description 1
- 229920002845 Poly(methacrylic acid) Polymers 0.000 description 1
- OFOBLEOULBTSOW-UHFFFAOYSA-N Propanedioic acid Natural products OC(=O)CC(O)=O OFOBLEOULBTSOW-UHFFFAOYSA-N 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 229920002125 Sokalan® Polymers 0.000 description 1
- FEWJPZIEWOKRBE-UHFFFAOYSA-N Tartaric acid Natural products [H+].[H+].[O-]C(=O)C(O)C(O)C([O-])=O FEWJPZIEWOKRBE-UHFFFAOYSA-N 0.000 description 1
- WGLPBDUCMAPZCE-UHFFFAOYSA-N Trioxochromium Chemical compound O=[Cr](=O)=O WGLPBDUCMAPZCE-UHFFFAOYSA-N 0.000 description 1
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 1
- KVUUQMDVROTSNI-UHFFFAOYSA-N [morpholin-4-yl(phosphono)methyl]phosphonic acid Chemical compound OP(O)(=O)C(P(O)(O)=O)N1CCOCC1 KVUUQMDVROTSNI-UHFFFAOYSA-N 0.000 description 1
- 235000011054 acetic acid Nutrition 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- GONOPSZTUGRENK-UHFFFAOYSA-N benzyl(trichloro)silane Chemical compound Cl[Si](Cl)(Cl)CC1=CC=CC=C1 GONOPSZTUGRENK-UHFFFAOYSA-N 0.000 description 1
- 229910000423 chromium oxide Inorganic materials 0.000 description 1
- 235000015165 citric acid Nutrition 0.000 description 1
- 239000012459 cleaning agent Substances 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- YOCUPQPZWBBYIX-UHFFFAOYSA-N copper nickel Chemical compound [Ni].[Cu] YOCUPQPZWBBYIX-UHFFFAOYSA-N 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000001784 detoxification Methods 0.000 description 1
- XBDQKXXYIPTUBI-UHFFFAOYSA-N dimethylselenoniopropionate Natural products CCC(O)=O XBDQKXXYIPTUBI-UHFFFAOYSA-N 0.000 description 1
- 238000002845 discoloration Methods 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 235000019253 formic acid Nutrition 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 239000000174 gluconic acid Substances 0.000 description 1
- 235000012208 gluconic acid Nutrition 0.000 description 1
- 150000004676 glycans Chemical class 0.000 description 1
- 239000000383 hazardous chemical Substances 0.000 description 1
- 230000036541 health Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 229910000040 hydrogen fluoride Inorganic materials 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- 150000002505 iron Chemical class 0.000 description 1
- AQBLLJNPHDIAPN-LNTINUHCSA-K iron(3+);(z)-4-oxopent-2-en-2-olate Chemical compound [Fe+3].C\C([O-])=C\C(C)=O.C\C([O-])=C\C(C)=O.C\C([O-])=C\C(C)=O AQBLLJNPHDIAPN-LNTINUHCSA-K 0.000 description 1
- NPFOYSMITVOQOS-UHFFFAOYSA-K iron(III) citrate Chemical compound [Fe+3].[O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O NPFOYSMITVOQOS-UHFFFAOYSA-K 0.000 description 1
- VZCYOOQTPOCHFL-UPHRSURJSA-N maleic acid Chemical compound OC(=O)\C=C/C(O)=O VZCYOOQTPOCHFL-UPHRSURJSA-N 0.000 description 1
- 239000011976 maleic acid Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 229910052750 molybdenum Inorganic materials 0.000 description 1
- 239000011733 molybdenum Substances 0.000 description 1
- DUWWHGPELOTTOE-UHFFFAOYSA-N n-(5-chloro-2,4-dimethoxyphenyl)-3-oxobutanamide Chemical compound COC1=CC(OC)=C(NC(=O)CC(C)=O)C=C1Cl DUWWHGPELOTTOE-UHFFFAOYSA-N 0.000 description 1
- FUZZWVXGSFPDMH-UHFFFAOYSA-N n-hexanoic acid Natural products CCCCCC(O)=O FUZZWVXGSFPDMH-UHFFFAOYSA-N 0.000 description 1
- GQPLMRYTRLFLPF-UHFFFAOYSA-N nitrous oxide Inorganic materials [O-][N+]#N GQPLMRYTRLFLPF-UHFFFAOYSA-N 0.000 description 1
- 231100000252 nontoxic Toxicity 0.000 description 1
- 230000003000 nontoxic effect Effects 0.000 description 1
- 235000006408 oxalic acid Nutrition 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 150000003009 phosphonic acids Chemical class 0.000 description 1
- 239000004584 polyacrylic acid Substances 0.000 description 1
- 229920001282 polysaccharide Polymers 0.000 description 1
- 239000005017 polysaccharide Substances 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 235000019260 propionic acid Nutrition 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- LJRGBERXYNQPJI-UHFFFAOYSA-M sodium;3-nitrobenzenesulfonate Chemical compound [Na+].[O-][N+](=O)C1=CC=CC(S([O-])(=O)=O)=C1 LJRGBERXYNQPJI-UHFFFAOYSA-M 0.000 description 1
- 235000002906 tartaric acid Nutrition 0.000 description 1
- 239000011975 tartaric acid Substances 0.000 description 1
- 231100000419 toxicity Toxicity 0.000 description 1
- 230000001988 toxicity Effects 0.000 description 1
- VZCYOOQTPOCHFL-UHFFFAOYSA-N trans-butenedioic acid Natural products OC(=O)C=CC(O)=O VZCYOOQTPOCHFL-UHFFFAOYSA-N 0.000 description 1
- 239000002351 wastewater Substances 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
- 239000011701 zinc Substances 0.000 description 1
- 229910052725 zinc Inorganic materials 0.000 description 1
- 229910000859 α-Fe Inorganic materials 0.000 description 1
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
- C23G—CLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS
- C23G1/00—Cleaning or pickling metallic material with solutions or molten salts
- C23G1/02—Cleaning or pickling metallic material with solutions or molten salts with acid solutions
- C23G1/08—Iron or steel
- C23G1/086—Iron or steel solutions containing HF
-
- 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
- C23G—CLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS
- C23G1/00—Cleaning or pickling metallic material with solutions or molten salts
- C23G1/02—Cleaning or pickling metallic material with solutions or molten salts with acid solutions
- C23G1/08—Iron or steel
- C23G1/088—Iron or steel solutions containing organic acids
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D1/00—Electroforming
- C25D1/06—Wholly-metallic mirrors
Definitions
- the invention relates to a means for pickling the surface of Chromium-nickel steels and chromium steels, which sulfuric acid, Contains phosphoric acid or mixtures thereof and Fe (III) ions. Furthermore, the invention relates to the use of a corresponding By means of an electrochemical and / or chemical Process for pickling the surface of stainless steel or Nickel steels.
- Pickling and cleaning agents known in the prior art for Chromium-nickel and chromium steels usually contain an active one Acid and an inhibiting or oxidizing component.
- active components get sulfuric acid, hydrochloric acid and / or Hydrofluoric acid used.
- inhibiting or oxidizing Component usually serves nitric acid.
- the pickling process serves, among other things, to remove impurities to be eliminated by foreign metals (e.g. ferrite contamination). It is also a result of heat treatment or scaling or tarnishing colors created during welding as well fix organic contaminants and a metallic one to create pure surface. This is the requirement for the fact that the chromium content of the alloy and the surrounding oxygen a closed, corrosion-resistant Form a chromium oxide layer on the workpiece surface can. Only this forms the basis for the desired one Corrosion resistance of the materials.
- Pickling agents according to the prior art generally contain Hydrofluoric acid as an active component and nitric acid as an oxidizing component.
- the nitric acid also inhibits the attack the hydrofluoric acid on the metal surface, so that this Attack mainly on the oxides and metallic contaminants aligns and thus promotes the dissolution of the oxides becomes.
- EP-A-0 501 867 discloses a method for the treatment of Steels, in which the pickling agent components include Sulfuric acid or phosphoric acid together with iron ions be proposed. The process comes first the redox potential of the treatment bath on one hold certain value. According to the only embodiment is called hydrogen fluoride with a concentration of 80 g / l used.
- a process for pickling stainless steel is known from EP-A-0 505 606, in which, in addition to sulfuric acid and iron 3+ ions, the HF concentration must be at least 40 g / l. H 2 O 2 is also required as the oxidizing agent. Finally, the redox potential of the treatment solution must also be kept at a certain value in this process.
- a pickling agent is known from US Pat. No. 3,785,866, which is particularly suitable for pickling zinc surfaces.
- this mordant may contain fluoroboric acid as the proton-providing source.
- such a mordant can contain iron (III) sulfate, fluoroboric acid and sulfuric acid.
- certain additives such as sodium fluoroborate or ammonium fluoroborate, can be added to a pickling agent for chromium-containing steels which contains 20-400 g / l sulfuric acid.
- a method for pickling stainless steel is known from US Pat. No. 3,010,854, a solution comprising nitric acid, phosphoric acid and fluorosilicates being used. The fluorosilicates can also be replaced by HBF 4 .
- the problem of the present invention is a Means for pickling and / or cleaning the surfaces of stainless steel and provide chrome steels that reduce environmental pollution and hazards from those in the prior art avoid known agents with nitric acid and hydrofluoric acid or reduced.
- Such a means should also meet the requirements for such Means for cleaning and pickling are sufficient.
- it depends on the effect of the agent largely on the undesirable oxide deposits and impurities judges.
- the appearance and structure of the metallic At the same time, the surface should be largely preserved stay.
- nitric acid and Hydrofluoric acid can be completely dispensed with.
- the agents according to the invention preferably contain the Fe (III) ions in the form of their water-soluble salts with a concentration up to 5% by weight, preferably 0.5 to 3% by weight.
- Suitable water-soluble salts are iron (III) sulfate, Iron (III) citrate or iron (III) acetylacetonate.
- the fluoroboric acid has a concentration in aqueous solution proven from 0.1 to 5.0 wt .-%. It was surprisingly found that by means of fluoroboric acid a faster and more thorough pickling effect is achieved than with fluorosilicic acid.
- the agents according to the invention can but also hydrofluoric acid (HF) in a concentration of up to 0.5 % By weight, preferably 0.2 to 0.4% by weight.
- HF hydrofluoric acid
- the Hydrofluoric acid is used here only in very low concentrations the disadvantages of the prior art do not occur to the same extent as there. But in particular there is none Addition of nitric acid required. The product is therefore non-toxic in accordance with the Ordinance on Hazardous Substances.
- the agent usually contains pickling and / or cleaning of metal surfaces an acid or acids and their mixtures in concentrations of 2 to 70% by weight, preferably from 15 to 35% by weight.
- These acids in addition to sulfuric acid especially phosphoric acid and amidosulfonic acid serve essentially for dissolving tarnishing colors in heat affected zones and scale layers in the weld area.
- inorganic and / or organic acids can be used in the agents according to the invention.
- An effective improvement of the agents has been shown if additionally 0.1 to 30% by weight of substituted or unsubstituted carboxylic acids with 1 to 6 carbon atoms or polycarboxylic acids are used. Of these acids, 0.1 to 10% by weight are preferably used.
- the substituted and unsubstituted carboxylic acids with 1 to 6 carbon atoms are, for example: Citric acid, oxalic acid, formic acid, gluconic acid, maleic acid, tartaric acid, acetic acid, propanoic acid, etc.
- polycarboxylic acids such as polyacrylic acid can also be used or polymethacrylic acid are used.
- Farther can be derivatives of the abovementioned acids or polyacids are used, such as hexanoic acid diamide and succinic acid diamide and their mixtures.
- chelating agents can affect the pickling effect Improve agents according to the invention.
- a chelating agent can advantageously phosphonic acids, especially hydroxyethane-1,1-diphosphonic acid or morpholinomethane diphosphonic acid, preferred in a concentration of 0.1 to 5% by weight will.
- the agents according to the invention can contain an oxidizing agent for the oxidation of scale layers; these oxidizing agents are preferred in amounts of 1 to 3% by weight.
- an oxidizing agent for the oxidation of scale layers these oxidizing agents are preferred in amounts of 1 to 3% by weight.
- one or more nitro-substituted aromatic compounds with one or more NO 2 groups bonded to the aromatic ring nucleus in addition to a water-solubilizing group, also bonded to an aromatic nucleus, such as sodium m-nitrobenzenesulfonate or m-nitrobenzenesulfonic acid can be used.
- the agents according to the invention can moreover be the usual ones Contain amounts of surfactants.
- the agents according to the invention can be both liquid and immersion and Riesling also thickened by a suitable thickener such as barium sulfate, aerosil, lumic acid, etc as spreadable or sprayable pickling paste.
- a suitable thickener such as barium sulfate, aerosil, lumic acid, etc as spreadable or sprayable pickling paste.
- the funds work particularly good in the temperature range from 10 ° C to 80 ° C.
- Surfactants in concentrations can also be used as further constituents of 0.1-2% by weight.
- the rest (to 100 wt .-%) exists then optionally from other strong acids - at least 10% by weight, for example phosphoric acid and / or known thickeners.
- the invention furthermore relates to the use of the agent according to the invention in an electrochemical and / or chemical process for pickling surfaces of chromium-nickel steels and chromium steels. It has proven to be particularly advantageous if an anodic current density of 0.2 to 30 A / dm 2 is used in an electrochemical process.
- the method according to the invention can be used in particular for descaling of metallic surfaces are used, whereby other electrochemical treatment steps such as Can connect electropolishing.
- the invention now represents an environmentally friendly and health less dangerous agent for pickling and / or cleaning of metallic surfaces.
- As a special advantage of the agent according to the invention or the method according to the invention shows that with regard to the required pickling effect a significant reduction in the pickling time can be obtained.
- composition 2 Phosphoric acid 85% 16.0% by weight 96% sulfuric acid 32.0 " Iron (III) sulfate 1.9 " Wetting agent 0.2 " Butyl glycol 3.0 " 1-hydroxyethane-1,1-diphosphonic acid 0.5 " Sodium salt of m-nitrobenzenesulfonic acid 2.3 " Succinic acid diamide 1.0 " 100% tetrafluoroboric acid 1.7 " water 41.4 " total 100.0% by weight
- composition 3 Phosphoric acid 85% 24.0% by weight 96% sulfuric acid 18.0 " Amidosulfonic acid 3.0 " 1-hydroxyethane-1,1-diphosphonic acid 3.0 " Butyl glycol 1.0 " Sodium salt of m-nitrobenzenesulfonic acid 2.0 " Iron (III) sulfate 0.8 " 100% tetrafluoroboric acid 1.7 " water 46.3% by weight 100.0% by weight
- Stainless steel sheets as before were made with a composition treated according to DE 37 42 367 Al (Example 1).
- the stainless steel sheets 30, 60, 120 and 180 were welded Stained for minutes at 23 ° C.
- the mordant according to the prior art had the following composition. Nitric acid (100%) 18% by weight Fluorosilicic acid (100%) 6 " water 75.09 " Surfactant 0.01 " Polysaccharide 0.90 "
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Abstract
Description
Die Erfindung betrifft ein Mittel zum Beizen der Oberfläche von Chromnickelstählen und Chromstählen, welches Schwefelsäure, Phosphorsäure oder deren Mischungen und Fe(III)-Ionen enthält. Weiterhin betrifft die Erfindung die Verwendung eines entsprechenden Mittels in einem elektrochemischen und/oder chemischen Verfahren zum Beizen der Oberfläche von Chromnickelstählen oder Nickelstählen.The invention relates to a means for pickling the surface of Chromium-nickel steels and chromium steels, which sulfuric acid, Contains phosphoric acid or mixtures thereof and Fe (III) ions. Furthermore, the invention relates to the use of a corresponding By means of an electrochemical and / or chemical Process for pickling the surface of stainless steel or Nickel steels.
Im Stand der Technik bekannte Beiz- und Reinigungsmittel für Chromnickel- und Chromstähle enthält gewöhnlich eine aktive Säure sowie eine inhibierende bzw. oxidierende Komponente. Als aktive Komponenten gelangen Schwefelsäure, Salzsäure und/oder Flußsäure zum Einsatz. Als inhibierende bzw. oxidierende Komponente dient in der Regel Salpetersäure.Pickling and cleaning agents known in the prior art for Chromium-nickel and chromium steels usually contain an active one Acid and an inhibiting or oxidizing component. As active components get sulfuric acid, hydrochloric acid and / or Hydrofluoric acid used. As inhibiting or oxidizing Component usually serves nitric acid.
Diese Mittel werden sowohl flüssig in Tauchbädern oder als Rieselbeizen als auch verdickt zu streich- oder sprühfähigen Pasten zur lokalen Schweißnahtbehandlung oder Behandlung großflächiger freistehender Werkstücke eingesetzt. Das Beizen der Oberfläche von Chromnickelstählen und Chromstählen ist die Voraussetzung für die gewünschte Korrosionsbeständigkeit dieser Werkstoffe.These agents become both liquid in immersion baths or as trickle stains as well as thickened to spreadable or sprayable Pastes for local weld treatment or treatment large free-standing workpieces are used. The pickling The surface of chrome nickel steels and chrome steels is the Prerequisite for the desired corrosion resistance Materials.
Der Beizvorgang dient unter anderem dazu, Verunreinigungen durch Fremdmetalle (z. B. Ferritkontamination) zu beseitigen. Darüberhinaus geht es darum, in Folge einer Wärmebehandlung oder beim Schweißen entstandenen Zunder oder Anlauffarben sowie organische Verunreinigungen zu beheben und eine metallisch reine Oberfläche zu schaffen. Diese ist die Voraussetzung dafür, daß sich anschließend aus dem Chromgehalt der Legierung und dem Sauerstoff der Umgebung eine geschlossene, korrosionsbeständige Chromoxidschicht auf der Werkstückoberfläche ausbilden kann. Erst diese bildet die Grundlage für die gewünschte Korrosionsbeständigkeit der Werkstoffe. The pickling process serves, among other things, to remove impurities to be eliminated by foreign metals (e.g. ferrite contamination). It is also a result of heat treatment or scaling or tarnishing colors created during welding as well fix organic contaminants and a metallic one to create pure surface. This is the requirement for the fact that the chromium content of the alloy and the surrounding oxygen a closed, corrosion-resistant Form a chromium oxide layer on the workpiece surface can. Only this forms the basis for the desired one Corrosion resistance of the materials.
Beizmittel nach dem Stand der Technik enthalten in der Regel Flußsäure als aktive und Salpetersäure als oxidierende Komponente. Die Salpetersäure inhibiert darüberhinaus den Angriff der Flußsäure auf die Metalloberfläche, so daß sich dieser Angriff überwiegend auf die Oxide und metallischen Verunreinigungen richtet und somit die Auflösung der Oxide gefördert wird.Pickling agents according to the prior art generally contain Hydrofluoric acid as an active component and nitric acid as an oxidizing component. The nitric acid also inhibits the attack the hydrofluoric acid on the metal surface, so that this Attack mainly on the oxides and metallic contaminants aligns and thus promotes the dissolution of the oxides becomes.
Sowohl Flußsäure als auch Salpetersäure stellen bei ihrer Anwendung in Beizmitteln nach dem Stand der Technik eine besondere Gefährdung für Bedienungspersonal als auch die Umwelt dar. Deshalb ist deren Anwendung strengen gesetzlichen Auflagen hinsichtlich der Arbeitssicherheit aber auch der Umweltbelastungen unterworfen.Both hydrofluoric acid and nitric acid make up their application a special one in pickling agents according to the prior art Danger for operating personnel as well as the environment. Therefore, their application is subject to strict legal requirements occupational safety but also environmental pollution subject.
Es besteht ein steigendes Bedürfnis nach Chromstahl und Chromnickelstahl mit einer besonderen Korrosionsbeständigkeit. Diese Korrosionsbeständigkeit sollte aber durch ein Beizen erzielbar sein, bei dem sowohl die Gefährdung der Umwelt als auch des Bedienungspersonals minimiert wird.There is an increasing need for chrome steel and chrome nickel steel with a special corrosion resistance. This Corrosion resistance should, however, be achieved by pickling be in which both the danger to the environment and the Operator is minimized.
Aus der DE-A-3 742 367 ist ein Beizmittel bekannt, in dem die Flußsäure durch Fluorkieselsäure ersetzt ist. Voraussetzung für die Wirksamkeit dieses Beizmittels ist aber ein Gehalt von 10 bis 30 Gew.-% Salpetersäure. Dieses Mittel weist zwar nicht die Giftigkeit der sonst im Stand der Technik verwendeten Beizmittel auf, jedoch ergeben sich beim Einsatz diverse Nachteile.From DE-A-3 742 367 a pickling agent is known in which the Hydrofluoric acid is replaced by fluorosilicic acid. requirement for however, the effectiveness of this pickling agent is 10 up to 30% by weight of nitric acid. This means does not have the Toxicity of the mordants otherwise used in the prior art on, but there are various disadvantages when used.
Bei der Anwendung dieses Mittels entstehen nämlich hochgiftige nitrose Gase, die eine sorgfältige Erfassung und Behandlung der Abluft sowie einen entsprechenden Schutz des Bedienungspersonals erforderlich machen. Darüberhinaus enthalten die beim Abspülen der gebeizten Oberflächen anfallenden Spülwässer neben Nitrat noch giftiges Nitrit, welches eine aufwendige Entgiftung/Entfernung im Rahmen der ordnungsgemäßen Behandlung der Abwässer erfordert. When using this agent, namely highly toxic nitrous gases, the careful detection and treatment of Exhaust air and appropriate protection for the operating personnel make necessary. In addition, they contain when rinsing of the stained surfaces of the rinse water Nitrate is still toxic nitrite, which is a costly detoxification / removal as part of the proper treatment of the Wastewater required.
Aus der US-A-947 067 ist ein Verfahren zum Beizen von Nickelkupferlegierungen bekannt. Bei diesem Beizverfahren werden neben Schwefelsäure Eisen(III)-Salze eingesetzt. Die verwendete Beizlösung aus einer freien Säure und dem Eisensalz bewirkt, daß die Oxide des Nickels und Kupfers von der Oberfläche des Metalls entfernt werden und zugleich die Ausfällung von Kupfer, welches sich von der Metalloberfläche abgelöst hat, durch Nickel verhindert wird.From US-A-947 067 is a method for pickling nickel copper alloys known. With this pickling process in addition to sulfuric acid, iron (III) salts are used. The one used Causes pickling solution from a free acid and the iron salt, that the oxides of nickel and copper from the surface of the Metal are removed and at the same time the precipitation of copper, which has detached from the metal surface by Nickel is prevented.
Die EP-A-0 501 867 offenbart ein Verfahren zur Behandlung von Stählen, bei dem als Beizmittelbestandteile unter anderem Schwefelsäure oder Phosphorsäure zusammen mit Eisenionen vorgeschlagen werden. Bei dem Verfahren kommt es vor allem darauf an, das Redox-Potential des Behandlungsbades auf einem bestimmten Wert zu halten. Nach dem einzigen Ausführungsbeispiel wird als Säure Fluorwasserstoff mit einer Konzentration von 80 g/l verwendet.EP-A-0 501 867 discloses a method for the treatment of Steels, in which the pickling agent components include Sulfuric acid or phosphoric acid together with iron ions be proposed. The process comes first the redox potential of the treatment bath on one hold certain value. According to the only embodiment is called hydrogen fluoride with a concentration of 80 g / l used.
Aus der EP-A-0 505 606 ist ein Verfahren zum Beizen von rostfreiem Stahl bekannt, in dem neben Schwefelsäure und Eisen3+-Ionen die HF-Konzentration mindestens 40 g/l betragen muß. Zusätzlich ist als Oxidationsmittel H2O2 erforderlich. Schließlich ist auch bei diesem Verfahren das Redox-Potential der Behandlungslösung auf einem bestimmten Wert zu halten.A process for pickling stainless steel is known from EP-A-0 505 606, in which, in addition to sulfuric acid and iron 3+ ions, the HF concentration must be at least 40 g / l. H 2 O 2 is also required as the oxidizing agent. Finally, the redox potential of the treatment solution must also be kept at a certain value in this process.
Aus der US-A-3 785 866 ist ein Beizmittel bekannt, das insbesondere zum Beizen von Zinkoberflächen geeignet ist. Dieses Beizmittel kann neben anderen Säuren als Protonen-liefernde Quelle Fluorborsäure enthalten. Insbesondere kann ein solches Beizmittel Eisen(III)-Sulfat, Fluorborsäure und Schwefelsäure enthalten. Aus der JP-A-61 276 999 ist bekannt, daß einem Beizmittel für Chrom enthaltende Stähle, das 20-400 g/l Schwefelsäure enthält, bestimmte Zusätze, wie beispielsweise Natriumfluorborat oder Ammoniumfluorborat zugegeben werden können. Aus der US-A-3 010 854 ist ein Verfahren zum Beizen von rostfreiem Stahl bekannt, wobei eine Lösung, die Salpetersäure, Phosphorsäure und Fluorsilikate enthält, eingesetzt wird. Die Fluorsilikate können auch durch HBF4 ersetzt werden. A pickling agent is known from US Pat. No. 3,785,866, which is particularly suitable for pickling zinc surfaces. In addition to other acids, this mordant may contain fluoroboric acid as the proton-providing source. In particular, such a mordant can contain iron (III) sulfate, fluoroboric acid and sulfuric acid. From JP-A-61 276 999 it is known that certain additives, such as sodium fluoroborate or ammonium fluoroborate, can be added to a pickling agent for chromium-containing steels which contains 20-400 g / l sulfuric acid. A method for pickling stainless steel is known from US Pat. No. 3,010,854, a solution comprising nitric acid, phosphoric acid and fluorosilicates being used. The fluorosilicates can also be replaced by HBF 4 .
Das Problem der vorliegenden Erfindung besteht darin, ein Mittel zum Beizen und/oder Reinigen der Oberflächen von Chromnickelstählen und Chromstählen bereitzustellen, das die Umweltbelastungen und Gefährdungen durch die im Stand der Technik bekannten Mittel mit Salpetersäure und Flußsäure vermeidet bzw. vermindert.The problem of the present invention is a Means for pickling and / or cleaning the surfaces of stainless steel and provide chrome steels that reduce environmental pollution and hazards from those in the prior art avoid known agents with nitric acid and hydrofluoric acid or reduced.
Ein solches Mittel soll aber zugleich den Anforderungen an derartige Mittel beim Reinigen und Beizen genügen. Hierbei kommt es unter anderem darauf an, daß die Wirkung des Mittels sich weitgehend auf die unerwünschten Oxidbeläge und Verunreinigungen richtet. Das Aussehen und die Struktur der metallischen Oberfläche soll dabei aber zugleich weitestgehend erhalten bleiben. Such a means should also meet the requirements for such Means for cleaning and pickling are sufficient. Here comes among other things, it depends on the effect of the agent largely on the undesirable oxide deposits and impurities judges. The appearance and structure of the metallic At the same time, the surface should be largely preserved stay.
Dieses Problem wird durch ein Mittel zum Beizen von Oberflächen von Chromnickelstählen und Chromstählen gelöst, welches Schwefelsäure, Phosphorsäure oder deren Mischungen und Fe(III)-Ionen enthält, welches dadurch gekennzeichnet ist, daß es Fluorborsäure in einer Konzentration von 0,1 bis 5 Gew.-% sowie höchstens 0,5 Gew.-% Flußsäure enthält, wobei die Konzentration an Fe(III)-Ionen (berechnet als Eisen(III)-Sulfat) 0,5 - 5 Gew.-% beträgt.This problem is solved by a means of pickling surfaces of chromium-nickel steels and chromium steels, which contains sulfuric acid, Phosphoric acid or mixtures thereof and Fe (III) ions contains, which is characterized in that it is fluoroboric acid in a concentration of 0.1 to 5 wt .-% as well contains at most 0.5 wt .-% hydrofluoric acid, the concentration on Fe (III) ions (calculated as iron (III) sulfate) 0.5 - 5 % By weight.
Bei diesem erfindungsgemäßen Mittel kann auf Salpetersäure sowie Flußsäure vollständig verzichtet werden.In this agent according to the invention, nitric acid and Hydrofluoric acid can be completely dispensed with.
Die erfindungsgemäßen Mittel enthalten die Fe(III)-Ionen vorzugsweise in Form ihrer wasserlöslichen Salze mit einer Konzentration von bis zu 5 Gew.-%, vorzugsweise 0,5 bis 3 Gew.-%. Als wasserlösliche Salze eignen sich Eisen(III)-Sulfat, Eisen(III)-Citrat oder Eisen(III)-Acetylacetonat.The agents according to the invention preferably contain the Fe (III) ions in the form of their water-soluble salts with a concentration up to 5% by weight, preferably 0.5 to 3% by weight. Suitable water-soluble salts are iron (III) sulfate, Iron (III) citrate or iron (III) acetylacetonate.
Die Fluorborsäure hat sich in wäßriger Lösung mit einer Konzentration von 0,1 bis 5,0 Gew.-% bewährt. Es wurde überraschenderweise festgestellt, daß mittels der Fluorborsäure eine schnellere und gründlichere Beizwirkung erzielt wird als mit Fluorkieselsäure.The fluoroboric acid has a concentration in aqueous solution proven from 0.1 to 5.0 wt .-%. It was surprisingly found that by means of fluoroboric acid a faster and more thorough pickling effect is achieved than with fluorosilicic acid.
Neben der Fluorborsäure können die erfindungsgemäßen Mittel aber auch Flußsäure (HF) in einer Konzentration von bis zu 0,5 Gew.-%, vorzugsweise 0,2 bis 0,4 Gew.-%, enthalten. Dabei stellt sich eine Verstärkung der Beizwirkung ein. Dies ist häufig insbesondere erforderlich bei Edelstählen mit höheren Anteilen an Nickel, Chrom, sowie Molybdän, da diese in der Regel schwerer lösliche Zunderschichten aufweisen. Da die Flußsäure hier aber nur in sehr geringen Konzentrationen verwendet wird, treten die Nachteile des Standes der Technik nicht im gleichen Maße wie dort auf. Insbesondere ist aber auch kein Zusatz von Salpetersäure erforderlich. Das Produkt ist somit gemäß Gefahrstoffverordnung ungiftig. In addition to fluoroboric acid, the agents according to the invention can but also hydrofluoric acid (HF) in a concentration of up to 0.5 % By weight, preferably 0.2 to 0.4% by weight. Here there is an intensification of the pickling effect. This is often particularly necessary for stainless steels with higher Shares in nickel, chrome, and molybdenum, as these in the Usually have layers of scale that are less soluble. Since the Hydrofluoric acid is used here only in very low concentrations the disadvantages of the prior art do not occur to the same extent as there. But in particular there is none Addition of nitric acid required. The product is therefore non-toxic in accordance with the Ordinance on Hazardous Substances.
Üblicherweise enthält das Mittel zum Beizen und/oder Reinigen von Metalloberflächen eine Säure oder Säuren sowie deren Mischungen in Konzentrationen von 2 bis 70 Gew.-%, vorzugsweise von 15 bis 35 Gew.-%. Diese Säuren, neben der Schwefelsäure insbesondere Phosphorsäure und Amidosulfonsäure, dienen im wesentlichen zur Auflösung von Anlauffarben in Wärmeeinflußzonen und Zunderschichten im Schweißnahtbereich.The agent usually contains pickling and / or cleaning of metal surfaces an acid or acids and their mixtures in concentrations of 2 to 70% by weight, preferably from 15 to 35% by weight. These acids, in addition to sulfuric acid especially phosphoric acid and amidosulfonic acid serve essentially for dissolving tarnishing colors in heat affected zones and scale layers in the weld area.
Daneben können weitere anorganische und/oder organische Säuren
in den erfindungsgemäßen Mitteln zum Einsatz gelangen. Es hat
sich eine wirkungsmäßige Verbesserung der Mittel gezeigt, wenn
zusätzlich 0,1 bis 30 Gew.-% substituierte oder unsubstituierte
Carbonsäuren mit 1 bis 6 Kohlenstoffatomen oder Polycarbonsäuren
verwendet werden. Von diesen Säuren gelangen vorzugsweise
0,1 bis 10 Gew.-% zum Einsatz. Bei den substituierten und
unsubstituierten Carbonsäuren mit 1 bis 6 Kohlenstoffatomen
handelt es sich beispielsweise um:
Zitronensäure, Oxalsäure, Ameisensäure, Gluconsäure,
Maleinsäure, Weinsäure, Essigsäure, Propansäure,
etc.In addition, other inorganic and / or organic acids can be used in the agents according to the invention. An effective improvement of the agents has been shown if additionally 0.1 to 30% by weight of substituted or unsubstituted carboxylic acids with 1 to 6 carbon atoms or polycarboxylic acids are used. Of these acids, 0.1 to 10% by weight are preferably used. The substituted and unsubstituted carboxylic acids with 1 to 6 carbon atoms are, for example:
Citric acid, oxalic acid, formic acid, gluconic acid, maleic acid, tartaric acid, acetic acid, propanoic acid, etc.
Darüberhinaus können aber auch Polycarbonsäuren wie Polyacrylsäure oder Polymethacrylsäure zum Einsatz gelangen. Weiterhin können Derivate der vorstehend genannten Säuren bzw. Polysäuren verwendet werden, so wie Hexansäurediamid und Bernsteinsäurediamid und deren Mischungen.In addition, polycarboxylic acids such as polyacrylic acid can also be used or polymethacrylic acid are used. Farther can be derivatives of the abovementioned acids or polyacids are used, such as hexanoic acid diamide and succinic acid diamide and their mixtures.
Weiterhin kann die Anwesenheit von Chelatbildnern die Beizwirkung erfindungsgemäßer Mittel verbessern. Als Chelatbildner können vorteilhaft Phosphonsäuren, insbesondere Hydroxyethan-1,1-Diphosphonsäure oder Morpholinomethandiphosphonsäure, bevorzugt in einer Konzentration von 0,1 bis 5 Gew.-%, eingesetzt werden. Furthermore, the presence of chelating agents can affect the pickling effect Improve agents according to the invention. As a chelating agent can advantageously phosphonic acids, especially hydroxyethane-1,1-diphosphonic acid or morpholinomethane diphosphonic acid, preferred in a concentration of 0.1 to 5% by weight will.
Darüberhinaus können die erfindungsgemäßen Mittel ein Oxidationsmittel zur Aufoxidation von Zunderschichten enthalten, bevorzugt sind diese Oxidationsmittel in Mengen von 1 bis 3 Gew.-%. Hierzu können erfindungsgemäß eine oder mehrere nitrosubstituierte aromatische Verbindungen mit einer oder mehreren NO2-Gruppen gebunden an den aromatischen Ringkern nebst einer wasserlöslichmachenden Gruppe, ebenfalls gebunden an einen aromatischen Kern, wie beispielsweise Natrium-m-Nitrobenzolsulfonat oder m-Nitrobenzolsulfonsäure verwendet werden.In addition, the agents according to the invention can contain an oxidizing agent for the oxidation of scale layers; these oxidizing agents are preferred in amounts of 1 to 3% by weight. For this purpose, according to the invention, one or more nitro-substituted aromatic compounds with one or more NO 2 groups bonded to the aromatic ring nucleus in addition to a water-solubilizing group, also bonded to an aromatic nucleus, such as sodium m-nitrobenzenesulfonate or m-nitrobenzenesulfonic acid, can be used.
Die erfindungsgemäßen Mittel können darüberhinaus die üblichen Mengen an Tensiden enthalten.The agents according to the invention can moreover be the usual ones Contain amounts of surfactants.
Die erfindungsgemäßen Mittel können sowohl flüssig als Tauch- und Rieselbeize aber auch verdickt durch ein geeignetes Verdickungsmittel wie Bariumsulfat, Aerosil, Luminsäure, etc als streich- oder sprühfähige Beizpaste vorliegen. Die Mittel arbeiten besonders gut im Temperaturbereich von 10°C bis 80°C.The agents according to the invention can be both liquid and immersion and Riesling also thickened by a suitable thickener such as barium sulfate, aerosil, lumic acid, etc as spreadable or sprayable pickling paste. The funds work particularly good in the temperature range from 10 ° C to 80 ° C.
Typischerweise setzen sich die erfindungsgemäßen Mittel wie folgt zusammen:
- 15-35 Gew.-%
- Schwefelsäure oder Schwefelsäure/Phosphorsäuremischung
- 0,5-3 Gew.-%
- Eisen(III)-Salze, berechnet als Eisen(III)-Sulfat
- 0,1-5,0 Gew.-%
- Fluorborsäure
- 0,2-0,4 Gew.-%
- Flußsäure
- 15-35% by weight
- Sulfuric acid or sulfuric acid / phosphoric acid mixture
- 0.5-3% by weight
- Iron (III) salts, calculated as iron (III) sulfate
- 0.1-5.0% by weight
- Fluoroboric acid
- 0.2-0.4% by weight
- Hydrofluoric acid
Als weitere Bestandteile haben sich bewährt (jeweils einzeln oder in Kombination):
- 0,1-10 Gew.-%
- substituierte oder unsubstituierte Carbonsäuren mit 1 bis 6 Kohlenstoffatomen und/oder entsprechende Polycarbonsäuren
- 0,1-5 Gew.-%
- Chelatbildner
- 1-3 Gew.-%
- Oxidationsmittel
- 0.1-10% by weight
- Substituted or unsubstituted carboxylic acids with 1 to 6 carbon atoms and / or corresponding polycarboxylic acids
- 0.1-5% by weight
- Chelating agent
- 1-3% by weight
- Oxidizing agent
Als weitere Bestandteile können auch Tenside in Konzentrationen von 0,1-2 Gew.-% vorhanden sein. Der Rest (auf 100 Gew.-%) besteht dann gegebenenfalls aus weiteren starken Säuren - mindestens 10 Gew.-%, beispielsweise Phosphorsäure - und/oder an sich bekannten Verdickungsmitteln.Surfactants in concentrations can also be used as further constituents of 0.1-2% by weight. The rest (to 100 wt .-%) exists then optionally from other strong acids - at least 10% by weight, for example phosphoric acid and / or known thickeners.
Gegenstand der Erfindung ist darüberhinaus die Verwendung des erfindungsgemäßen Mittels in einem elektrochemischen und/oder chemischen Verfahren zum Beizen von Oberflächen von Chromnickelstählen und Chromstählen. Als besonders vorteilhaft hat sich herausgestellt, wenn in einem elektrochemischem Verfahren mit einer anodischen Stromdichte von 0,2 bis 30 A/dm2 gearbeitet wird.The invention furthermore relates to the use of the agent according to the invention in an electrochemical and / or chemical process for pickling surfaces of chromium-nickel steels and chromium steels. It has proven to be particularly advantageous if an anodic current density of 0.2 to 30 A / dm 2 is used in an electrochemical process.
Das erfindungsgemäße Verfahren kann insbesondere zur Entzunderung von metallischen Oberflächen eingesetzt werden, wobei sich weitere elektrochemische Behandlungsschritte wie zum Beispiel Elektropolieren anschließen können.The method according to the invention can be used in particular for descaling of metallic surfaces are used, whereby other electrochemical treatment steps such as Can connect electropolishing.
Die Erfindung stellt nun ein umweltschonendes und die Gesundheit weniger gefährdendes Mittel zum Beizen und/oder Reinigen von metallischen Oberflächen bereit. Als besonderer Vorteil des erfindungsgemäßen Mittels bzw. des erfindungsgemäßen Verfahrens zeigt sich, daß hinsichtlich der erforderlichen Beizwirkung eine deutliche Verkürzung der Beizzeit erhalten werden kann. The invention now represents an environmentally friendly and health less dangerous agent for pickling and / or cleaning of metallic surfaces. As a special advantage of the agent according to the invention or the method according to the invention shows that with regard to the required pickling effect a significant reduction in the pickling time can be obtained.
Die Erfindung wird in den folgenden Beispielen näher erläutert.The invention is explained in more detail in the following examples.
In den folgenden Beispielen wurden jeweils 10 x 10 cm Edelstahlbleche, die über ihren Querschnitt eine Schweißnaht aufwiesen, mit unterschiedlichen Mitteln in unterschiedlicher Weise behandelt.In the following examples, 10 x 10 cm stainless steel sheets were which had a weld seam over their cross section, with different means in different ways treated.
Es wurde ein Edelstahlblech mit einer Schweißnaht (10 x 10 cm)
jeweils 20, 30 und 40 Minuten bei 23°C in folgende Zusammensetzung
eingetaucht:
Es zeigte sich, daß sowohl die Schweißnaht als auch die Wärmeeinflußzone
bereits nach 20 Minuten zunderfrei war.
Selbst bei einer 40minütigen Behandlung der metallischen Oberfläche
wurde der Grundwerkstoff nicht angegriffen. It was found that both the weld seam and the heat affected zone were free of scale after only 20 minutes.
Even with a 40-minute treatment of the metallic surface, the base material was not attacked.
Unter gleichen Bedingungen wurden mit der folgenden Lösung
identische Ergebnisse erhalten.
In die folgende Zusammensetzung wurden wiederum Edelstahlbleche
(mit Schweißnaht) allerdings über 20 und 30 Minuten bei 40°C
getaucht.
Auch bei diesem Beispiel zeigte sich, daß nach 20 Minuten die Schweißnaht und die Wärmeeinflußzone vollständig entzundert war. Trotz der höheren Temperatur von 40°C wurde hier der Grundwerkstoff auch nach 30 minütiger Behandlung kaum angegriffen.This example also showed that after 20 minutes the Weld seam and the heat affected zone completely descaled was. Despite the higher temperature of 40 ° C, the base material was used here Hardly attacked even after 30 minutes of treatment.
Edelstahlbleche wie zuvor wurden mit einer Zusammensetzung gemäß der DE 37 42 367 Al behandelt (Beispiel 1). Die Edelstahlbleche mit Schweißnaht wurden jeweils 30, 60, 120 und 180 Minuten bei 23°C gebeizt.Stainless steel sheets as before were made with a composition treated according to DE 37 42 367 Al (Example 1). The stainless steel sheets 30, 60, 120 and 180 were welded Stained for minutes at 23 ° C.
Das Beizmittel gemäß dem Stand der Technik hatte folgende Zusammensetzung.
Selbst nach 30 und nach 60 Minuten konnte noch deutlich Zunder auf der Schweißnaht und der Wärmeeinflußzone beobachtet werden. Auch eine 180minütige Behandlung mit dieser Lösung nach dem Stand der Technik ergab noch etwas Zunderreste und Verfärbungen auf der Schweißnaht und der Wärmeeinflußzone.Even after 30 and 60 minutes, scale was still evident be observed on the weld seam and the heat affected zone. Also a 180 minute treatment with this solution after The state of the art revealed some scale residues and discoloration on the weld seam and the heat affected zone.
Claims (11)
- Composition for pickling the surface of chromium-nickel steels and chromium steels, which contains sulphuric acid, phosphoric acid or mixtures thereof and Fe(III) ions, characterized in that it contains fluoroboric acid in a concentration of from 0.1 to 5% by weight and also at most 0.5% by weight of hydrofluoric acid, in which the concentration of Fe(III) ions (calculated as iron(III) sulphate) is 0.5-5% by weight.
- Composition according to Claim 1, characterized in that it contains further inorganic and/or organic acids.
- Composition according to either of the preceding claims, characterized in that it contains hydrofluoric acid (HF) in a concentration of from 0.2 to 0.4% by weight.
- Composition according to any of the preceding claims, characterized in that it contains from 2 to 70% by weight of sulphuric acid, phosphoric acid and/or sulphamic acid.
- Composition according to Claim 1, characterized in that it contains from 0.1 to 30% by weight of substituted or unsubstituted carboxylic acids having from 1 to 6 carbon atoms or polycarboxylic acids.
- Composition according to any of Claims 1 to 5, characterized in that it contains an oxidizing agent.
- Composition according to Claim 6, characterized in that the oxidizing agent present comprises one or more nitro-substituted aromatic compounds.
- Composition according to any of Claims 1 to 7, characterized in that it contains chelating agents.
- Composition according to any of Claims 1 to 8, characterized in that it contains surfactants.
- Use of a composition according to any of Claims 1 to 9 in an electrochemical and/or chemical process for pickling the surface of chromium-nickel steels or chromium steels.
- Use according to Claim 10 in an electrochemical process which operates at an anodic current density of from 0.2 to 30 A/dm2.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE4237021A DE4237021C1 (en) | 1992-11-02 | 1992-11-02 | Means for pickling the surface of chromium-nickel steels and chrome steels and use of the agent |
| DE4237021 | 1992-11-02 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| EP0596273A1 EP0596273A1 (en) | 1994-05-11 |
| EP0596273B1 true EP0596273B1 (en) | 1998-05-06 |
Family
ID=6471947
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP93116251A Expired - Lifetime EP0596273B1 (en) | 1992-11-02 | 1993-10-07 | Product for pickling surfaces of chromium-nickel steel or chromium steel and its use |
Country Status (5)
| Country | Link |
|---|---|
| EP (1) | EP0596273B1 (en) |
| AT (1) | ATE165876T1 (en) |
| DE (2) | DE4237021C1 (en) |
| DK (1) | DK0596273T3 (en) |
| ES (1) | ES2114991T3 (en) |
Families Citing this family (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| BR9401214A (en) * | 1994-03-18 | 1995-10-24 | Frimox Quimica Ltda | Composition, solution and surface treatment process of ferrous materials |
| DE19833990A1 (en) | 1998-07-29 | 2000-02-10 | Metallgesellschaft Ag | Mordant for stainless steels |
| DE10110823A1 (en) * | 2001-03-07 | 2002-10-02 | Bosch Gmbh Robert | Process for removing material deposits that result from laser processing |
| EP1552035B1 (en) * | 2002-10-15 | 2010-08-25 | Henkel AG & Co. KGaA | Pickling solution and process for stainless steel |
| DE10341061B4 (en) * | 2003-09-05 | 2007-08-02 | Poligrat Gmbh | Electropolishing process for light metal alloys and electrolyte |
| DE102005055768A1 (en) * | 2005-11-21 | 2007-05-24 | Ralf Waldmann | Method and means for the electrolytic cleaning and descaling of a metallic workpiece |
| DE102007010538A1 (en) | 2007-03-05 | 2008-09-11 | Poligrat Gmbh | Process for the thermochemical passivation of stainless steel |
| DE102008021299A1 (en) * | 2008-04-21 | 2009-10-29 | Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. | Catalyst for toxic hydrocarbon compounds and / or organic compounds and process for its preparation |
| DE102016210289A1 (en) * | 2016-06-10 | 2017-12-14 | Henkel Ag & Co. Kgaa | Process for the purification pretreatment of iron-containing components assembled by welding |
| EP3269844A1 (en) * | 2016-07-11 | 2018-01-17 | Beratherm AG | Aqueous cleaning solution for removing blacking coverings on surfaces of stainless steels in contact with media and use thereof |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3010854A (en) * | 1954-12-31 | 1961-11-28 | Armco Steel Corp | Pickling solution and method |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US947067A (en) * | 1908-09-30 | 1910-01-18 | Int Nickel Co | Method of treating nickel-copper alloys. |
| GB891670A (en) * | 1957-09-04 | 1962-03-14 | English Electric Co Ltd | Improvements in and relating to the removing of scale from silicon iron and other metals |
| US3446715A (en) * | 1965-04-09 | 1969-05-27 | Oakite Prod Inc | Metal treating |
| JPS61235581A (en) * | 1985-04-12 | 1986-10-20 | C Uyemura & Co Ltd | Scale remover and method for removing scale |
| JPS61276999A (en) * | 1985-05-30 | 1986-12-06 | Nippon Steel Corp | Method for pickling steel sheet containing chromium |
| DE3742367A1 (en) * | 1987-12-14 | 1989-06-22 | Pelox Chemietechnik Gmbh Co Kg | Pickling and cleaning agent for metal surfaces |
| JPH0273983A (en) * | 1988-09-07 | 1990-03-13 | Nippon Parkerizing Co Ltd | Acidic washing solution for aluminum |
| FR2673200A1 (en) * | 1991-02-25 | 1992-08-28 | Ugine Aciers | METHOD FOR OVERDRAWING STEEL MATERIALS SUCH AS STAINLESS STEELS AND ALLIED STEELS. |
| IT1245594B (en) * | 1991-03-29 | 1994-09-29 | Itb Srl | PICKLING AND PASSIVATION PROCESS OF STAINLESS STEEL WITHOUT NITRIC ACID |
-
1992
- 1992-11-02 DE DE4237021A patent/DE4237021C1/en not_active Expired - Fee Related
-
1993
- 1993-10-07 DK DK93116251T patent/DK0596273T3/en active
- 1993-10-07 EP EP93116251A patent/EP0596273B1/en not_active Expired - Lifetime
- 1993-10-07 AT AT93116251T patent/ATE165876T1/en active
- 1993-10-07 ES ES93116251T patent/ES2114991T3/en not_active Expired - Lifetime
- 1993-10-07 DE DE59308502T patent/DE59308502D1/en not_active Expired - Fee Related
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3010854A (en) * | 1954-12-31 | 1961-11-28 | Armco Steel Corp | Pickling solution and method |
Also Published As
| Publication number | Publication date |
|---|---|
| ATE165876T1 (en) | 1998-05-15 |
| ES2114991T3 (en) | 1998-06-16 |
| DK0596273T3 (en) | 1999-02-15 |
| EP0596273A1 (en) | 1994-05-11 |
| DE4237021C1 (en) | 1994-02-10 |
| DE59308502D1 (en) | 1998-06-10 |
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