US2293779A - Metal coating method and article produced thereby - Google Patents
Metal coating method and article produced thereby Download PDFInfo
- Publication number
- US2293779A US2293779A US318935A US31893540A US2293779A US 2293779 A US2293779 A US 2293779A US 318935 A US318935 A US 318935A US 31893540 A US31893540 A US 31893540A US 2293779 A US2293779 A US 2293779A
- Authority
- US
- United States
- Prior art keywords
- nickel
- zinc
- coating
- phosphate
- solution
- 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
- 238000000576 coating method Methods 0.000 title description 34
- 229910052751 metal Inorganic materials 0.000 title description 13
- 239000002184 metal Substances 0.000 title description 13
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 47
- 239000011248 coating agent Substances 0.000 description 29
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 23
- 229910052725 zinc Inorganic materials 0.000 description 23
- 239000011701 zinc Substances 0.000 description 23
- 229910019142 PO4 Inorganic materials 0.000 description 21
- 229910052759 nickel Inorganic materials 0.000 description 21
- NBIIXXVUZAFLBC-UHFFFAOYSA-K phosphate Chemical compound [O-]P([O-])([O-])=O NBIIXXVUZAFLBC-UHFFFAOYSA-K 0.000 description 21
- 239000010452 phosphate Substances 0.000 description 21
- 229910000831 Steel Inorganic materials 0.000 description 11
- 239000010959 steel Substances 0.000 description 11
- 239000003973 paint Substances 0.000 description 8
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 8
- KRVSOGSZCMJSLX-UHFFFAOYSA-L chromic acid Substances O[Cr](O)(=O)=O KRVSOGSZCMJSLX-UHFFFAOYSA-L 0.000 description 5
- AWJWCTOOIBYHON-UHFFFAOYSA-N furo[3,4-b]pyrazine-5,7-dione Chemical compound C1=CN=C2C(=O)OC(=O)C2=N1 AWJWCTOOIBYHON-UHFFFAOYSA-N 0.000 description 5
- 238000010438 heat treatment Methods 0.000 description 5
- 238000000034 method Methods 0.000 description 5
- 150000003839 salts Chemical class 0.000 description 5
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 4
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 description 3
- 229910001297 Zn alloy Inorganic materials 0.000 description 3
- 238000000151 deposition Methods 0.000 description 3
- 229940116007 ferrous phosphate Drugs 0.000 description 3
- 229910000155 iron(II) phosphate Inorganic materials 0.000 description 3
- SDEKDNPYZOERBP-UHFFFAOYSA-H iron(ii) phosphate Chemical compound [Fe+2].[Fe+2].[Fe+2].[O-]P([O-])([O-])=O.[O-]P([O-])([O-])=O SDEKDNPYZOERBP-UHFFFAOYSA-H 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- QELJHCBNGDEXLD-UHFFFAOYSA-N nickel zinc Chemical compound [Ni].[Zn] QELJHCBNGDEXLD-UHFFFAOYSA-N 0.000 description 3
- 229910002651 NO3 Inorganic materials 0.000 description 2
- NHNBFGGVMKEFGY-UHFFFAOYSA-N Nitrate Chemical compound [O-][N+]([O-])=O NHNBFGGVMKEFGY-UHFFFAOYSA-N 0.000 description 2
- 238000010306 acid treatment Methods 0.000 description 2
- 238000005275 alloying Methods 0.000 description 2
- 238000005260 corrosion Methods 0.000 description 2
- 230000007797 corrosion Effects 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- 238000002844 melting Methods 0.000 description 2
- 230000008018 melting Effects 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- 239000007800 oxidant agent Substances 0.000 description 2
- 238000007747 plating Methods 0.000 description 2
- 239000007921 spray Substances 0.000 description 2
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 1
- 230000001680 brushing effect Effects 0.000 description 1
- 229910017052 cobalt Inorganic materials 0.000 description 1
- 239000010941 cobalt Substances 0.000 description 1
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 1
- 210000003298 dental enamel Anatomy 0.000 description 1
- NAAXGLXYRDSIRS-UHFFFAOYSA-L dihydrogen phosphate;manganese(2+) Chemical class [Mn+2].OP(O)([O-])=O.OP(O)([O-])=O NAAXGLXYRDSIRS-UHFFFAOYSA-L 0.000 description 1
- 239000008233 hard water Substances 0.000 description 1
- 229910017604 nitric acid Inorganic materials 0.000 description 1
- NBIIXXVUZAFLBC-UHFFFAOYSA-N phosphoric acid Substances OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
- LRXTYHSAJDENHV-UHFFFAOYSA-H zinc phosphate Chemical compound [Zn+2].[Zn+2].[Zn+2].[O-]P([O-])([O-])=O.[O-]P([O-])([O-])=O LRXTYHSAJDENHV-UHFFFAOYSA-H 0.000 description 1
- 229910000165 zinc phosphate Inorganic materials 0.000 description 1
- MFXMOUUKFMDYLM-UHFFFAOYSA-L zinc;dihydrogen phosphate Chemical compound [Zn+2].OP(O)([O-])=O.OP(O)([O-])=O MFXMOUUKFMDYLM-UHFFFAOYSA-L 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
- 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
- C23C22/00—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
- C23C22/78—Pretreatment of the material to be coated
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/12—All metal or with adjacent metals
- Y10T428/12493—Composite; i.e., plural, adjacent, spatially distinct metal components [e.g., layers, joint, etc.]
- Y10T428/12535—Composite; i.e., plural, adjacent, spatially distinct metal components [e.g., layers, joint, etc.] with additional, spatially distinct nonmetal component
- Y10T428/12583—Component contains compound of adjacent metal
Definitions
- This invention pertains to increasing the adhesion of paint to metal surfaces. tains to steel articles, and more especially steel sheets carrying a coating containing at least two other metals and a phosphate.
- Zinc coated steel sheets such as galvanized and galvanneal have been known for many years to V possess corrosion resistance superior to that of It also per,
- the new article in brief, is produced by coating the steel first with a thin layer of nickel, then with a layer of zinc over the nickel, and thereafter treating the article to obtain a phosphate coating on the surface.
- the coatings of nickel and zinc may be obtained by electrolytic methods for the best results.
- the steel sheet which is coated with the nickel and zinc may be heated, and this seems to be desirable for best results, Heating for a relatively long period at a temperature slightly below the melting point of zinc, or for a relatively short period at a temperature slightly above the melting point of zinc, has been found to be satisfactory.
- a temperature of 675 F. applied for a period of 5 /2 hours is suflicient. After the sheets have cooled, a thin film-of oxide is usually discernible on the surface.
- Some coatings obtained after heating when examined under the microscope show a layer of nickel next to the steel, a layer of nickel-zinc alloy, and then a layer of zinc beneath the thin oxide layer. Chemical analysis discloses the presence of nickel at the surface even when the microscopic appearance is as described in the last sentence. After treatment with the phosphate coating solution the article will, of course, be covered with a phosphate coating.
- the article obtained without the phosphate coating possesses satisfactory corrosion-resistance. It also has some drawing properties. However, adhesion of paint to the article is poorer. A, handicap of this nature obviously sheet because the great majority of articles which in their fabrication require the properties inherent in the described sheet, are usually painted. 1
- the articles were painted with a synthetic enamel, scratched diagonally across the face to'expose bare metal thru the paint and subjected to salt spray test. At the end of 160 hours the metal showed no creepage of the paint from the scratch. At the. end of 763 hours the paint on the treated metal was still in excellent condition.
- phosphate coating step was exemplifled above by use of a solution containing zinc dihydrogen phosphate and ferrous phosphate, it is understood that this is by way of example only and other phosphate coating solutions may be employed.
- solutions of ferrous phosphate alone have been found to give very satisfactory results and this is true also of zinc and manganese dihydrogenphosphates.
- an oxidizing agent such as nitrate
- the processing time for producing the is same amount of coating will be longer than that given in. the example.
- the nickel and zinc coated sheet is heated sumciently so that some nickel is alloyed with the zinc coat, or if the nickel is otherwise contacted by the phosphate solution, the nickel of the article tends to accelerate the coating action of the phosphate solution.
- the chromic acid rinse treatment acts to reduce to a minimum any blistering which may be caused by soluble salts left in the coating by improper water rinsing or by hard water salts present in the water rinse itself which follows the phosphate treatment. If after the coating operation a thorough rinse with clean water is used, the chromic acid treatment may be dispensed'with and ex cellent paint adhesion will still be obtained but for practical commercial operation the chromic acid treatment is recommended.
- Steel sheets carrying the coatings obtained in accordance with this invention may be manufactured into fabricated articles by steps such as drawing, welding, stamping, forming, etc.
- the phosphate coating should be ex.- tremely thin and for best results there should not be over .03 ounce per square foot of surface. of course the coatings may be obtained upon articles that already have been fabricated if desired.
- An article of manufacture comprising a sheet'having a ferrous base and carrying a coating containing metallic zinc, metallic nickel, nickel-zinc alloy and a phosphate coating chemically formed on the metal.
- An article of manufacture comprising a sheet having a ferrous base, said sheet carrying a coating of several layers, said layers appearing under the microscope to comprise, from the inner side outward in the order named, a layer of metallic nickel, a layer of nickel-zinc alloy, a layer of metallic zinc, and a layer comprising zinc phosphate chemically formed on the metal.
- a process which comprises applying'electrodeposited metallic nickel to a sheet of steel, electro-depositing metallic zinc onto the nickel coating, heating suiiiciently to produce some alloying of the nickel and zinc, and thereafter chemically forming a phosphate coating on the zinc.
- a process which comprises plating nickel on a ferrous surface, plating zinc on the nickel,
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- Chemical & Material Sciences (AREA)
- General Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Chemical Treatment Of Metals (AREA)
Description
Patented Aug. 25, 1942 NITED STATES PATENT oFFicE METAL. CO ATHVG IHETHOD AND ARTICLE PRODUCED THEBEBY Robert R. Tanner, Detroit, Mich, assignor to Parker Rust Proof Company, Detroit, Mich.
No Drawing. Application February 14, 194e,
' Serial No. 318,935
8 Claims.
This invention pertains to increasing the adhesion of paint to metal surfaces. tains to steel articles, and more especially steel sheets carrying a coating containing at least two other metals and a phosphate.
Zinc coated steel sheets such as galvanized and galvanneal have been known for many years to V possess corrosion resistance superior to that of It also per,
mg and paint-holding properties, believed to be superior to those of galvanized sheets. The new article, in brief, is produced by coating the steel first with a thin layer of nickel, then with a layer of zinc over the nickel, and thereafter treating the article to obtain a phosphate coating on the surface.
The coatings of nickel and zinc may be obtained by electrolytic methods for the best results. Prior to the application of the phosphate coating, the steel sheet which is coated with the nickel and zinc may be heated, and this seems to be desirable for best results, Heating for a relatively long period at a temperature slightly below the melting point of zinc, or for a relatively short period at a temperature slightly above the melting point of zinc, has been found to be satisfactory. A temperature of 675 F. applied for a period of 5 /2 hours is suflicient. After the sheets have cooled, a thin film-of oxide is usually discernible on the surface.
Some coatings obtained after heating when examined under the microscope show a layer of nickel next to the steel, a layer of nickel-zinc alloy, and then a layer of zinc beneath the thin oxide layer. Chemical analysis discloses the presence of nickel at the surface even when the microscopic appearance is as described in the last sentence. After treatment with the phosphate coating solution the article will, of course, be covered with a phosphate coating.
The article obtained without the phosphate coating possesses satisfactory corrosion-resistance. It also has some drawing properties. However, adhesion of paint to the article is poorer. A, handicap of this nature obviously sheet because the great majority of articles which in their fabrication require the properties inherent in the described sheet, are usually painted. 1
I have found that if the surface of the article after the treatment previously described, is treated with an acid phosphate solution for even a very short length of time, the paint adhesion is decidedly increased, as shown by a comparison between treated and untreated metal which was painted and subjected to salt spray, The steel article, after having been coated with nickel and zinc, then heated and cooled, may be immersed in a solution made up as follows:
Solution #1 Parts Solution #2 Parts Zinc metal Anhydrous zinc nitrata. 25 Iron 5. 5 Zinc dihydrogen phos- Phosphoric acid (75%) 33. 3 phate. 16 Water to make 42 Be. nitric acid 4 Water to make 100 To 100 gallons of water 25 pounds of solution #1 and 35 pounds of solution #2 are added. solution is heated to F. and the articles are immersed for five seconds or longer. A phosphate coating is obtained on the surface of the articles. The articles are then rinsed with water and then given a final rinse in a solution of chromic acid of the concentration of two grams per gallon of water for ten seconds at F. The articles thus obtained possess good corrosion resistance and provide improved paint adhesion.
In one test, the articles were painted with a synthetic enamel, scratched diagonally across the face to'expose bare metal thru the paint and subjected to salt spray test. At the end of 160 hours the metal showed no creepage of the paint from the scratch. At the. end of 763 hours the paint on the treated metal was still in excellent condition.
While the phosphate coating step was exemplifled above by use of a solution containing zinc dihydrogen phosphate and ferrous phosphate, it is understood that this is by way of example only and other phosphate coating solutions may be employed. For example, solutions of ferrous phosphate alone have been found to give very satisfactory results and this is true also of zinc and manganese dihydrogenphosphates. Where use is not made of an oxidizing agent such as nitrate, the processing time for producing the is same amount of coating will be longer than that given in. the example. Where-use is made of places a limitation on the use of this kind of 6 P p t s other t n ferrousphosphate, acce1- erating salts of metals below iron in the electromotive series may be used, such as nickel and cobalt. Other suitable oxidizing agents besides nitrate may be used providing they ar compatible with the solution. Likewise the coating solution may be applied hot or cold and by brushing or spraying as well as immersing.
If the nickel and zinc coated sheet is heated sumciently so that some nickel is alloyed with the zinc coat, or if the nickel is otherwise contacted by the phosphate solution, the nickel of the article tends to accelerate the coating action of the phosphate solution.
The chromic acid rinse treatment acts to reduce to a minimum any blistering which may be caused by soluble salts left in the coating by improper water rinsing or by hard water salts present in the water rinse itself which follows the phosphate treatment. If after the coating operation a thorough rinse with clean water is used, the chromic acid treatment may be dispensed'with and ex cellent paint adhesion will still be obtained but for practical commercial operation the chromic acid treatment is recommended.
Steel sheets carrying the coatings obtained in accordance with this invention may be manufactured into fabricated articles by steps such as drawing, welding, stamping, forming, etc. In
this case the phosphate coating should be ex.- tremely thin and for best results there should not be over .03 ounce per square foot of surface. of course the coatings may be obtained upon articles that already have been fabricated if desired.
What I claim is:
1. An article of manufacture comprising a sheet'having a ferrous base and carrying a coating containing metallic zinc, metallic nickel, nickel-zinc alloy and a phosphate coating chemically formed on the metal.
2. An article of manufacture comprising a sheet having a ferrous base, said sheet carrying a coating of several layers, said layers appearing under the microscope to comprise, from the inner side outward in the order named, a layer of metallic nickel, a layer of nickel-zinc alloy, a layer of metallic zinc, and a layer comprising zinc phosphate chemically formed on the metal.
3. A process which comprises applying'electrodeposited metallic nickel to a sheet of steel, electro-depositing metallic zinc onto the nickel coating, heating suiiiciently to produce some alloying of the nickel and zinc, and thereafter chemically forming a phosphate coating on the zinc.
4. A process which comprises plating nickel on a ferrous surface, plating zinc on the nickel,
subjecting the plated surface to heat until the exposed surface contains some nickel, and thereafter treating said exposed surface with a phosphate coating solution until a substantially in-" tegral phosphate coating is produced.
5. A process which comprises applying electro-deposited metallic nickel to a sheet of steel, electro-depositing metallic zinc on to the nickel coating, heating suiiiciently to produce some alloying of the nickel and zinc, and thereafter chemically forming a phosphate coating on the metal, then treating the phosphate coating with a solution of chromic acid. 6. A process which comprises applying electro-deposited metallic nickel to a sheet of steel, electro-depositing metallic zinc onto the nickel coating, heating sufiiciently to result in the presence of nickel in the exposed surface, treating.
present in the exposed surface, and thereafter treating the exposed surface with a phosphate coating solution until a substantially integral coating is formed thereon.
ROBERT R. TANNER.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US318935A US2293779A (en) | 1940-02-14 | 1940-02-14 | Metal coating method and article produced thereby |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US318935A US2293779A (en) | 1940-02-14 | 1940-02-14 | Metal coating method and article produced thereby |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US2293779A true US2293779A (en) | 1942-08-25 |
Family
ID=23240190
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US318935A Expired - Lifetime US2293779A (en) | 1940-02-14 | 1940-02-14 | Metal coating method and article produced thereby |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US2293779A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2698266A (en) * | 1951-07-02 | 1954-12-28 | American Chem Paint Co | Material for treating metal surfaces to improve corrosion resistance and paint bonding ability |
| US2847373A (en) * | 1953-11-12 | 1958-08-12 | Wean Engineering Co Inc | Electroplating zinc on basis metal |
| US2928762A (en) * | 1955-08-09 | 1960-03-15 | Neilson Chemical Company | Phosphate coating of metals |
| JPS5662987A (en) * | 1979-10-22 | 1981-05-29 | Toyo Kohan Co Ltd | Production of highly corrosion resistant multilayer plated metal plate |
| FR2519655A1 (en) * | 1982-01-11 | 1983-07-18 | Ebara Udylite Kk | CHROMATE COMPOSITION AND PROCESS FOR TREATING ZINC-NICKEL ALLOYS |
-
1940
- 1940-02-14 US US318935A patent/US2293779A/en not_active Expired - Lifetime
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2698266A (en) * | 1951-07-02 | 1954-12-28 | American Chem Paint Co | Material for treating metal surfaces to improve corrosion resistance and paint bonding ability |
| US2847373A (en) * | 1953-11-12 | 1958-08-12 | Wean Engineering Co Inc | Electroplating zinc on basis metal |
| US2928762A (en) * | 1955-08-09 | 1960-03-15 | Neilson Chemical Company | Phosphate coating of metals |
| JPS5662987A (en) * | 1979-10-22 | 1981-05-29 | Toyo Kohan Co Ltd | Production of highly corrosion resistant multilayer plated metal plate |
| FR2519655A1 (en) * | 1982-01-11 | 1983-07-18 | Ebara Udylite Kk | CHROMATE COMPOSITION AND PROCESS FOR TREATING ZINC-NICKEL ALLOYS |
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