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CN1867704A - Electrolytic method for phosphating metal surfaces and phosphated metal layer - Google Patents

Electrolytic method for phosphating metal surfaces and phosphated metal layer Download PDF

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Publication number
CN1867704A
CN1867704A CN200480030171.3A CN200480030171A CN1867704A CN 1867704 A CN1867704 A CN 1867704A CN 200480030171 A CN200480030171 A CN 200480030171A CN 1867704 A CN1867704 A CN 1867704A
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Prior art keywords
zinc
aforementioned
layer
alloy
electrolytic solution
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CN200480030171.3A
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CN1867704B (en
Inventor
J·哈肯伯格
D·齐默曼
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Robert Bosch GmbH
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Robert Bosch GmbH
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    • CCHEMISTRY; METALLURGY
    • C25ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25DPROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D3/00Electroplating: Baths therefor
    • C25D3/02Electroplating: Baths therefor from solutions
    • C25D3/56Electroplating: Baths therefor from solutions of alloys
    • C25D3/565Electroplating: Baths therefor from solutions of alloys containing more than 50% by weight of zinc
    • CCHEMISTRY; METALLURGY
    • C25ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25DPROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D11/00Electrolytic coating by surface reaction, i.e. forming conversion layers
    • C25D11/36Phosphatising

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Electroplating Methods And Accessories (AREA)
  • Chemical Treatment Of Metals (AREA)
  • Electroplating And Plating Baths Therefor (AREA)
  • Electrolytic Production Of Non-Metals, Compounds, Apparatuses Therefor (AREA)
  • Electrolytic Production Of Metals (AREA)

Abstract

The invention relates to a method for phosphating metal layers by electrodeposition from acidic aqueous solutions containing at least zinc ions and phosphate ions, and by using direct current. Electrodeposition of zinc takes place in the same electrolytes and at the same time as deposition of the phosphating layer. The current density lies in the region of > A/dm<2>.

Description

Be used for the electrolysis process on phosphated metal surface and phosphated thus metal level
Generality of the present invention relates to the electrolysis process that is used for the phosphated metal surface according to the preamble of claim 1.This method also relates to the phosphated metal level by this method preparation.
Background technology
The phosphoric acid zinc impregnation is to be widely used in the low alloy steel preserving method.Wherein in the precipitin reaction of pH value control, zinc phosphate crystal (hopeite) is deposited on the component surface.For energy sedimentary phosphor silicate layer, must surpass the solubility product of zinc phosphate.This is by corroding (pickling) (Fe>Fe for example to base metal 2++ 2 E-) and realize.D/d thus electronics is used to reduce proton.PH is to the extremely alkaline migration of neutrality and surpass solubility product.Usually form the thick layer of 2-3 μ m thus with about 90-95% coverage.Therefore the anticorrosion thin porous layer that is produced that is subject to also combines with other coatings (for example cosmoline or KTL) usually.Further the target of research is to avoid improving antiseptic property under the condition of these additional coatings.
A kind of technical scheme that is used to obtain than thick-layer is to use Faradaic current.But the pH that obtains regulating easily by electrolytic reaction moves and the growth of regulating course thus.
JP-A-85/211080 relates to a kind of method that produces corrosion protection coating by phosphoric acid zinc impregnation solution under the situation that intermittently applies cathodic current on the metallic surface.Wherein especially on the edge of pending metallic surface, also obtained corrosion resistant protective layer.
EP-A-0171790 discloses a kind of similar method.Wherein handle with the acidic aqueous solution that contains zine ion, phosphate anion and chlorion after the phosphoric acid zinc impregnation of routine the metallic surface, wherein applies direct current on the metallic surface of anodizing simultaneously.
By the known a kind of metal surface phosphor acidifying method that is used for of DE-4111186A1, be preferred for the phosphated method of electrogalvanizing or the galvanized surface of steel plate of melt impregnation, this method is wherein used the described workpiece of direct current anodizing simultaneously by carrying out with acidic aqueous phosphating solution processing in dipping or in the sprinkling dipping.Wherein handle by phosphating solution, this phosphating solution comprises the Zn of following component: 0.1-5g/l 2+Positively charged ion; The PO of 5-50g/l 4 3-Negatively charged ion; 0.1-50g/l NO 3 -Negatively charged ion; 0.1-5g/l Ni 2+The Co of positively charged ion and/or 0.1-5g/l 2+Positively charged ion.The pH value of this phosphating solution is 1.5-4.5, and the temperature of phosphating solution is 10-80 ℃.The galvanic current density of during phosphatization this workpiece being carried out anodizing is 0.01-100mA/cm 2
The defective of tradition phosphatization method is that it is confined to low alloy steel and Zn and Al, and the gained layer is owing to be to be constituted and do not had a cathodic protection by the zinc phosphate crystal.In addition, in most of the cases need to activate in advance.
Advantage of the present invention
With respect to prior art, the method that is used for the phosphated metal surface of the present invention has following advantage, promptly forms thickness and is close to the dense layer that can regulate arbitrarily.
Another advantage is that the gained layer has significantly higher erosion resistance.
In addition advantageously, can need not activation ground and carry out phosphatization.
Other favourable improvement of the present invention are provided by the measure of mentioning in the dependent claims.
Like this, electrolysis can be for example in constant voltage or constant current or under these two portions mix, carry out.
The accompanying drawing summary
Embodiments of the invention have been described in the drawings and description in more detail in the specification sheets of back.Accompanying drawing has shown preparation method's of the present invention schematic diagram.
Embodiment
Target of the present invention is to develop the electrolysis coating method that is used for the phosphated metal surface, and wherein the hole in phosphate layer is filled by metallic zinc or zinc alloy.The method according to this invention, in same electrolytic solution with form the electrolytic deposition that the zinc phosphate crystal side by side carries out zinc or zinc alloy.Method of the present invention is opposite with conventional phosphatization method, in ordinary method purify or pickling after in titanium phosphate suspension, flood workpiece (in pH~9 time about 60 seconds), method of the present invention then need not pre-reactivation process.At j=-10--50A/dm 2Current density under cambial speed be about 3-20 μ m/min, this is very fast.In the ordinary method of using so far, only deposit with about 1 μ m/min.Utilize aforesaid method, except low alloy steel, can also directly be coated with coating stainless steel and other precious metals and base metal material (for example Al, Al alloy, Cu, Cu alloy, Ni, Ni alloy etc.).In contrast, in currentless method, only can on permission pickling erosive material, deposit, because otherwise it can not reach above-mentioned required pH migration.Wherein said electrolysis both can also can be regulated on constant current ground on constant voltage ground, perhaps mixed with these two portions and carried out.
Formed dense layer by method of the present invention, this layer is characterised in that the space between the zinc phosphate crystal is filled by the zinc or the zinc alloy network of metal deposition.By forming the zinc or the zinc alloy of conduction simultaneously, the pH migration (promptly providing electronics by the outside) of electrolytic initiation can take place, and by the H at zinc surface +Reduction realize the almost bed thickness growth arbitrarily of zinc (zinc alloy)/zinc phosphate layer.
Described accompanying drawing shows the schematic diagram according to coating method of the present invention.Wherein, out-of-the-way sour zinc layer 14 is deposited on the base metal 11 with zinc by electrolytic solution 13 in a conventional electrolysis pond 10 with working electrode 11, and wherein said working electrode is made up of corresponding base metal and counter electrode 12.As mentioned above, opposite with the standard phosphatization, be used herein to the required electronics of pH migration and be not iron rot (pickling on base metal is corroded) from low alloy steel, but from external current source 15.This protective current especially also is used to make base metal 11 not weather.
About 3 μ m that can almost deposit sealing (promptly atresia) as far as possible by method of the present invention without restriction are to about 500 μ m mixolimnions (with the metal phosphate layer of zinc, zinc/nickel no bare substrate metal of filling for example).The layer that routine obtains has about 5 hours patience to forming iron rust in salt spray test, and can reach patience greater than 1000 hours by 20-30 μ m zinc/zinc phosphate mixolimnion in salt spray is tested.After 30 seconds phosphatization time, just reached and surpassed 420 hours erosion resistance.
Coating method of the present invention can carry out in the electrolyzer that routine is used.Wherein counter electrode both can be made of for example noble metal plate such as platinum, Pt/Ti or gold, also can be by constituting as base metal sacrificial anodes such as Zn, Ni, Fe, and this counter electrode is used for transporting continuously metal ion.Can use stainless steel and bronze, Cu, Cu alloy, Ni, Ni alloy etc. as the working electrode (base metal) that deposits described layer thereon.Electrolytic solution is the electrolytic solution that uses in not containing the phosphatization purposes of extrinsic current basically.Wherein said electrolytic solution can for example contain:
Zn 2+:5-50g/l
H 2PO 4 -:5-80g/l
For this reason, importantly use so-called high zinc to bathe (Hochzinkbad), its zinc content is greater than 5g/l, and zinc content only is about 1-5g/l in normal common low zinc is bathed, and wherein can not cause simple substance zinc or zinc alloy deposition between phosphate crystal.
In addition, described electrolytic solution can contain the ion that can form the element of alloy with zinc, makes deposition zinc alloy in deposition phosphatization layer.What it is also conceivable that is to add nano particle and organic molecule.Other possible bath additives that are used for layer is carried out modification are polyphosphate/ester, borate/ester, organic polyhydroxy compound, phosphoglyceride and fluorochemical.Can for example consider the ion of divalent metal M for additional ions, wherein other divalent metal M is selected from Ni, Fe, Co, Cu, Mn etc.
Described reaction can be carried out under the situation of adding or not adding accelerator.Can consider for example urea, nitrate, nitrite, oxymuriate, bromate, hydrogen peroxide, ozone, organic nitro-body, superoxide, oxyamine or their mixture as accelerator.As the accelerator nitrate ion in the 0-20g/l scope advantageously.The pH value of bathing is 1.5-4, is preferably 2.5-3.5. and can deposits binary alloy, ternary alloy or more senior alloy by adding Zn salt, Ni salt, Co salt, Fe salt or Mn salt.Metal ion also can be supplied with electrolytic solution by anode dissolution.
Aspect electrolytic condition, described electrolytic solution can be immobilized or mobile in described technology.Current density is greater than-1A/dm 2And preferably be in about j=-1 to about j=-100A/dm 2Between.Especially preferred be current density-5~-50A/dm 2Between.Electrolyte temperature is greater than 40 ℃ and is preferably 40~80 ℃, especially preferred 60~70 ℃.
As mentioned above, electrolytic process both can also can be regulated and control on constant current ground on constant voltage ground, wherein can use direct current or pulse direct current.By regulating local current densities, promptly pass through typing and/or mixed flow between anode and the workpiece, can regulate layer thickness distribution.Can also apply geometrical shape by this way and require harsh parts.

Claims (20)

1. the method for phosphated metal layer, it is undertaken by using under the galvanic situation electrolytic deposition by acidic aqueous solution at the same time, this acidic aqueous solution contains zine ion and phosphate anion at least, described method is characterised in that, carry out the electrolytic deposition of zinc in same electrolytic solution in deposition phosphatization layer, wherein current density is greater than-5A/dm 2
2. the method for claim 1 is characterized in that, described current density is-5~50A/dm 2
3. claim 1 or 2 method is characterized in that temperature is greater than 40 ℃ and be preferably 40~80 ℃, especially 60~70 ℃.
4. each method among the claim 1-3 is characterized in that, the contained zine ion of described electrolytic solution is greater than 5g/l, and especially 5-50g/l, and institute phosphorus-containing acid ion is greater than 10g/l, especially 10-80g/l.
5. each method among the claim 1-4 is characterized in that, described acidic aqueous solution also contains the ion that can form the element of alloy with zinc, makes deposition zinc and/or zinc alloy in deposition phosphatization layer.
6. the method for claim 5 is characterized in that, uses nano particle or organic molecule to substitute described ion.
7. the method for claim 5 is characterized in that, described other ions are ions of divalent metal M.
8. the method for claim 7 is characterized in that, described other divalent metals M is selected from Ni, Fe, Co, Cu, Mn etc.
9. each method is characterized in that in the aforementioned claim, and described metal level is selected from stainless steel, bronze, Al, Al alloy, Cu, Cu alloy, Ni, Ni alloy etc.
10. each method is characterized in that in the aforementioned claim, and the pH value of described electrolytic solution is about 1.5~about 4, preferred about 2.5~about 3.5.
11. each method is characterized in that in the aforementioned claim, adds accelerator in described electrolytic solution.
12. the method for claim 11 is characterized in that, described accelerator is selected from urea, nitrate, nitrite, oxymuriate, bromate, hydrogen peroxide, ozone, organic nitro-body, superoxide, oxyamine or their mixture.
13. the method for claim 7 is characterized in that, the metal ion of divalent metal M is supplied with by the ionogen anode dissolution.
14. each method is characterized in that in the aforementioned claim, the extra salt that adds Zn salt, Ni salt, Co salt and/or Mn in electrolytic solution.
15. each method is characterized in that in the aforementioned claim, described electrolytic solution has following composition:
-?Zn 2+?5-40g/l;
-?M 2+ 0.5-10g/l;
-H 2PO 4 -10-40g/l; With
-?NO 3 -?1-10g/l。
16. each method is characterized in that in the aforementioned claim, described electrolysis constant voltage or constant current or two portions mixing are carried out.
17. each method is characterized in that in the aforementioned claim, the layer thickness distribution on metal level is regulated by local current densities.
18. each method is characterized in that in the aforementioned claim, described direct current is pulse.
19. each method is characterized in that in the aforementioned claim, layer formation speed is the about 20 μ m/ of about 3-minutes.
20. deposit the metal level of porous calcium phosphate zinc layer on it, it is characterized in that the hole of described zinc phosphate layer is filled with metallic zinc and/or zinc alloy.
CN200480030171.3A 2003-10-16 2004-09-22 Electrolytic method for phosphating metal surfaces and phosphated metal layer Expired - Fee Related CN1867704B (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE10348251.2 2003-10-16
DE10348251A DE10348251A1 (en) 2003-10-16 2003-10-16 Electrolytic process for phosphating metal surfaces and phosphated metal layer
PCT/EP2004/052269 WO2005038095A2 (en) 2003-10-16 2004-09-22 Electrolytic method for phosphating metal surfaces and phosphated metal layer

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CN1867704A true CN1867704A (en) 2006-11-22
CN1867704B CN1867704B (en) 2012-03-14

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US (1) US20070295608A1 (en)
EP (1) EP1675975A2 (en)
JP (1) JP2007508457A (en)
CN (1) CN1867704B (en)
BR (1) BRPI0415520A (en)
DE (1) DE10348251A1 (en)
TR (1) TR200601814T1 (en)
WO (1) WO2005038095A2 (en)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101643928B (en) * 2009-09-09 2011-01-05 重庆科技学院 Method for electrodepositing phosphate/metal composite film on cathode of surface of magnesium alloy
CN102212864A (en) * 2011-06-10 2011-10-12 沈阳理工大学 Method for modifying electrolysis phosphorization membrane
CN103517811A (en) * 2011-05-09 2014-01-15 克诺尔-布里姆斯轨道车辆系统有限公司 Rail wheel and method for producing a rail wheel
CN105951155A (en) * 2016-06-01 2016-09-21 中钢集团郑州金属制品研究院有限公司 Online double phosphating method for steel wires and continuous production equipment for method
CN107630243A (en) * 2017-10-16 2018-01-26 浙江五源科技股份有限公司 A kind of electrolytic preparation method of complex phosphate coating
CN114737179A (en) * 2022-05-05 2022-07-12 东南大学 High-temperature alloy heat-resistant phosphating film, and preparation method and application thereof

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DE102006035974A1 (en) * 2006-08-02 2008-02-07 Robert Bosch Gmbh Process for phosphating a metal layer
MX2010014396A (en) * 2008-06-18 2011-06-17 Massachusetts Inst Technology Catalytic materials, electrodes, and systems for water electrolysis and other electrochemical techniques.
DE102010030465B4 (en) 2010-06-24 2023-12-07 Bayerische Motoren Werke Aktiengesellschaft Method for producing a sheet metal part from a high-strength steel sheet material with an electrolytically applied zinc-nickel coating
US9393759B2 (en) * 2013-10-24 2016-07-19 General Electric Company Metal laminate structures with systems and methods for treating
DE102016100245A1 (en) 2016-01-08 2017-07-13 Staku Anlagenbau Gmbh Self-lubricating electrodeposited phosphating coating
CN114824263B (en) * 2021-01-29 2024-03-19 中南大学 Zn@Zn-E composite negative electrode, preparation method thereof and application thereof in water-based zinc ion battery
CN114883560B (en) * 2021-02-05 2024-03-19 中南大学 A three-dimensional current collector/Zn/Zn-E composite negative electrode and its preparation and application in aqueous zinc-ion batteries

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2540314A (en) * 1947-07-24 1951-02-06 Parker Rust Proof Co Process and compositions for applying phosphate coatings
GB1041761A (en) * 1964-08-13 1966-09-07 Pyrene Co Ltd Improvements in the coating of metals
US3449229A (en) * 1966-08-08 1969-06-10 Hooker Chemical Corp Electrophoretic deposition on zinc enriched metal surface
JP2534280B2 (en) * 1987-02-05 1996-09-11 日本パーカライジング株式会社 Zinc-based composite plating metal material and plating method
US5232523A (en) * 1989-03-02 1993-08-03 Nippon Paint Co., Ltd. Phosphate coatings for metal surfaces
JPH0336296A (en) * 1989-06-29 1991-02-15 Nippon Parkerizing Co Ltd Surface treatment of stainless steel
JPH0436498A (en) * 1990-06-01 1992-02-06 Nippon Parkerizing Co Ltd Surface treatment of steel wire
US5645706A (en) * 1992-04-30 1997-07-08 Nippondenso Co., Ltd. Phosphate chemical treatment method
JP2000144494A (en) * 1998-09-11 2000-05-26 Nippon Parkerizing Co Ltd Method of forming lubricating film for cold heading
JP2000160394A (en) * 1998-12-01 2000-06-13 Nippon Parkerizing Co Ltd Short-time phosphate treatment method for iron-based metallic materials
JP4870872B2 (en) * 2001-02-23 2012-02-08 株式会社キリウ Rotating brake member for vehicle brake device and rust prevention treatment method thereof

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101643928B (en) * 2009-09-09 2011-01-05 重庆科技学院 Method for electrodepositing phosphate/metal composite film on cathode of surface of magnesium alloy
CN103517811A (en) * 2011-05-09 2014-01-15 克诺尔-布里姆斯轨道车辆系统有限公司 Rail wheel and method for producing a rail wheel
CN103517811B (en) * 2011-05-09 2016-10-05 克诺尔-布里姆斯轨道车辆系统有限公司 Rail wheel and the method being used for manufacturing rail wheel
CN102212864A (en) * 2011-06-10 2011-10-12 沈阳理工大学 Method for modifying electrolysis phosphorization membrane
CN105951155A (en) * 2016-06-01 2016-09-21 中钢集团郑州金属制品研究院有限公司 Online double phosphating method for steel wires and continuous production equipment for method
CN107630243A (en) * 2017-10-16 2018-01-26 浙江五源科技股份有限公司 A kind of electrolytic preparation method of complex phosphate coating
CN107630243B (en) * 2017-10-16 2019-07-02 浙江五源科技股份有限公司 A kind of electrolytic preparation method of complex phosphate coating
CN114737179A (en) * 2022-05-05 2022-07-12 东南大学 High-temperature alloy heat-resistant phosphating film, and preparation method and application thereof
CN114737179B (en) * 2022-05-05 2024-05-24 东南大学 High-temperature alloy heat-resistant phosphating film, and preparation method and application thereof

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Publication number Publication date
US20070295608A1 (en) 2007-12-27
TR200601814T1 (en) 2007-01-22
EP1675975A2 (en) 2006-07-05
CN1867704B (en) 2012-03-14
DE10348251A1 (en) 2005-05-12
BRPI0415520A (en) 2006-12-26
JP2007508457A (en) 2007-04-05
WO2005038095A2 (en) 2005-04-28
WO2005038095A3 (en) 2005-07-14

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