US3388050A - Anodized aluminum alloy product - Google Patents
Anodized aluminum alloy product Download PDFInfo
- Publication number
- US3388050A US3388050A US485630A US48563065A US3388050A US 3388050 A US3388050 A US 3388050A US 485630 A US485630 A US 485630A US 48563065 A US48563065 A US 48563065A US 3388050 A US3388050 A US 3388050A
- Authority
- US
- United States
- Prior art keywords
- anodized
- aluminum alloy
- aluminum
- alloy product
- anodized aluminum
- 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
- 229910000838 Al alloy Inorganic materials 0.000 title description 3
- 229910052782 aluminium Inorganic materials 0.000 claims description 11
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 11
- MUBZPKHOEPUJKR-UHFFFAOYSA-N Oxalic acid Chemical compound OC(=O)C(O)=O MUBZPKHOEPUJKR-UHFFFAOYSA-N 0.000 description 19
- 239000003792 electrolyte Substances 0.000 description 8
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 6
- 235000006408 oxalic acid Nutrition 0.000 description 5
- 229910052776 Thorium Inorganic materials 0.000 description 4
- 229910045601 alloy Inorganic materials 0.000 description 4
- 239000000956 alloy Substances 0.000 description 4
- 229910052751 metal Inorganic materials 0.000 description 4
- 239000002184 metal Substances 0.000 description 4
- 229910052719 titanium Inorganic materials 0.000 description 4
- 229910052726 zirconium Inorganic materials 0.000 description 4
- 238000007789 sealing Methods 0.000 description 3
- AXIFGFAGYFPNFC-UHFFFAOYSA-I 2-hydroxy-2-oxoacetate;niobium(5+) Chemical compound [Nb+5].OC(=O)C([O-])=O.OC(=O)C([O-])=O.OC(=O)C([O-])=O.OC(=O)C([O-])=O.OC(=O)C([O-])=O AXIFGFAGYFPNFC-UHFFFAOYSA-I 0.000 description 2
- XOGQNIQICBURCO-UHFFFAOYSA-I C(C(=O)[O-])(=O)O.[Ta+5].C(C(=O)[O-])(=O)O.C(C(=O)[O-])(=O)O.C(C(=O)[O-])(=O)O.C(C(=O)[O-])(=O)O Chemical compound C(C(=O)[O-])(=O)O.[Ta+5].C(C(=O)[O-])(=O)O.C(C(=O)[O-])(=O)O.C(C(=O)[O-])(=O)O.C(C(=O)[O-])(=O)O XOGQNIQICBURCO-UHFFFAOYSA-I 0.000 description 2
- 229910052783 alkali metal Inorganic materials 0.000 description 2
- 150000001340 alkali metals Chemical class 0.000 description 2
- 238000007743 anodising Methods 0.000 description 2
- 239000000470 constituent Substances 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 229910052758 niobium Inorganic materials 0.000 description 2
- 239000010955 niobium Substances 0.000 description 2
- 229910052763 palladium Inorganic materials 0.000 description 2
- 229910052697 platinum Inorganic materials 0.000 description 2
- 229910052573 porcelain Inorganic materials 0.000 description 2
- 229910052715 tantalum Inorganic materials 0.000 description 2
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 1
- MQRWBMAEBQOWAF-UHFFFAOYSA-N acetic acid;nickel Chemical compound [Ni].CC(O)=O.CC(O)=O MQRWBMAEBQOWAF-UHFFFAOYSA-N 0.000 description 1
- 238000005275 alloying Methods 0.000 description 1
- 239000002585 base Substances 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- KGBXLFKZBHKPEV-UHFFFAOYSA-N boric acid Chemical compound OB(O)O KGBXLFKZBHKPEV-UHFFFAOYSA-N 0.000 description 1
- 239000004327 boric acid Substances 0.000 description 1
- 238000005266 casting Methods 0.000 description 1
- 229940011182 cobalt acetate Drugs 0.000 description 1
- QAHREYKOYSIQPH-UHFFFAOYSA-L cobalt(II) acetate Chemical compound [Co+2].CC([O-])=O.CC([O-])=O QAHREYKOYSIQPH-UHFFFAOYSA-L 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- IRXRGVFLQOSHOH-UHFFFAOYSA-L dipotassium;oxalate Chemical compound [K+].[K+].[O-]C(=O)C([O-])=O IRXRGVFLQOSHOH-UHFFFAOYSA-L 0.000 description 1
- 229910052737 gold Inorganic materials 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
- 239000000155 melt Substances 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 229940078494 nickel acetate Drugs 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 229910052709 silver Inorganic materials 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D11/00—Electrolytic coating by surface reaction, i.e. forming conversion layers
- C25D11/02—Anodisation
- C25D11/04—Anodisation of aluminium or alloys based thereon
- C25D11/14—Producing integrally coloured layers
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C21/00—Alloys based on aluminium
Definitions
- the anodized, sealed products of this invention are characterized by a semi-white porcelain like finish which is suitable, before sealing, for the reception of decorative or other impregnants.
- the alloys to which the invention applies are obtained by induction melting suitable starting materials, e.g. ingot aluminum and a binary master alloy of aluminum containing about 50% of the desired alloying element and then after the melt has reached the proper fluidity and uniformity, casting it into shapes suitable for working to the desired structural product such as sheet or plate.
- suitable starting materials e.g. ingot aluminum and a binary master alloy of aluminum containing about 50% of the desired alloying element
- a 1% sulfuric acid electrolyte prepared by adding 1 gram of 98% sulfuric acid to 99 cc. of water, is utilized at a temperature of 50 C., a voltage of 20 to 25 volts, a current density of about 16 to 18 amperes per square foot for about 20 to 30 minutes.
- sealing of the anodized surface is accom" plished in a boiling solution containing 0.5% nickel acetate, 0.5% cobalt acetate and 1% boric acid, or in any other convenient sealing composition.
- Aluminum articles having at least one anodized surface formed of an alloy consisting essentially of between 1% and 4% of metal selected from the group consisting of Ti, Zr, Nb, Ta and Th; between 0.01 and 0.1% of a metal selected from the group consisting of Tg, A-u, Pd, and Pt; and the balance substantially all Al.
- Aluminum articles as in claim 1 which have been anodized in an electrolyte comprising oxalic acid and at least one additional oxalate.
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Mechanical Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Electrolytic Production Of Metals (AREA)
Description
United States Patent 3,388,050 ANGDlZED ALUMINUM ALLOY PRODUCT Eugene Wainer, Shaker Heights, Ohio, assignor to Horizons incorporated, a corporation of New Jersey No Drawing. Filed Sept. 7, 1965, Ser. No. 485,630 6 Claims. (Cl. 20458) This invention relates to anodized materials having a semi-porcelain finish and a pleasing appearance which renders them suitable as architectural materials, e.g. as building panels.
More particularly, it relates to the products obtained when articles having surfaces consisting of aluminum alloys containing between 1 and 4% of a metal selected from the group consisting of Ti, Zr, Nb, Ta and Th as essential constituents and between 0.01 and 0.1% of a metal selected from the group consisting of Ag, Au, Pd and Pt as an optical constituent are anodized and then sealed in the usual way. The anodized, sealed products of this invention are characterized by a semi-white porcelain like finish which is suitable, before sealing, for the reception of decorative or other impregnants.
The alloys to which the invention applies are obtained by induction melting suitable starting materials, e.g. ingot aluminum and a binary master alloy of aluminum containing about 50% of the desired alloying element and then after the melt has reached the proper fluidity and uniformity, casting it into shapes suitable for working to the desired structural product such as sheet or plate.
To achieve the desired finish it is preferred to anodize the articles after they have been cleaned and degreased by conventional techniques using one of the following:
(1) A 1% sulfuric acid electrolyte, prepared by adding 1 gram of 98% sulfuric acid to 99 cc. of water, is utilized at a temperature of 50 C., a voltage of 20 to 25 volts, a current density of about 16 to 18 amperes per square foot for about 20 to 30 minutes.
(2) An oxalic solution containing 3 to 5 percent oxalic acid by weight and optionally up to 3% of a sodium or potassium oxalate, utilized at a temperature of 50 to 55 C. for about 30 minutes, at a voltage of 40 to 50 volts and a current density of to amperes per square foot.
(3) An oxalic acid electrolyte as in 2 and containing 2 to 4 percent of an alkali metal double oxalate of Ti, Zr or Th, operated at to 30 amperes per square foot, about 120 volts, and at a temperature of 50 C. for 20 to 40 minutes, the pH being kept between 1.6 and 3.0.
(4) An oxalic acid electrolyte as in 2 and containing 2 to 4 percent of at least one oxalate from the group tantalum hydrogen oxalate and niobium hydrogen oxalate 3,388,050 Patented June 11, 1968 "ice and optionally 2 to 4 percent of an alkali metal double oxalate of Ti, Zr or Th, operated at about 50-55 C. at 40 to volt and 14 to 16 amperes per square foot for about 30 minutes.
The anodizing processes are carried out in the usual manner described in many patents and in the text Finishing of Aluminum by S. Wernick and R. Pinner published 1959 in England, but the invention resides in the anodizing of the specific aluminum base alloy described above to obtain a novel product not heretofore available.
Preferably sealing of the anodized surface is accom" plished in a boiling solution containing 0.5% nickel acetate, 0.5% cobalt acetate and 1% boric acid, or in any other convenient sealing composition.
I claim:
1. Aluminum articles having at least one anodized surface formed of an alloy consisting essentially of between 1% and 4% of metal selected from the group consisting of Ti, Zr, Nb, Ta and Th; between 0.01 and 0.1% of a metal selected from the group consisting of Tg, A-u, Pd, and Pt; and the balance substantially all Al.
2. Aluminum articles as in claim 1 which have been anodized in a 1% sulfuric acid electrolyte.
3. Aluminum articles as in claim 1 which have been anodized in an oxalic acid electrolyte.
4. Aluminum articles as in claim 1 which have been anodized in an electrolyte comprising oxalic acid and at least one additional oxalate.
5. Aluminum articles as in claim 1 which have been anodized in an electrolyte containing tantalum hydrogen oxalate.
6. Aluminum articles as in claim 1 which have been anodized in an electrolyte containing niobium hydrogen oxalate.
References Cited UNITED STATES PATENTS 1,912,382 6/1933 Nock 138 1,946,150 2/1934 Tosterud 20458 XR 2,050,587 8/1936 Ruben 75-138 XR 2,056,604 10/1936 Guertler 75138 2,231,373 2/1941 Schenk 20458 XR 2,260,278 10/1941 Schenk 20458 2,262,967 11/ 1941 Schenk 20458 2,272,779 2/1942 Sarbey 75138 XR 2,798,037 7/1957 Robinson 20458 XR 2,966,735 1/1961 Towner et al 75138 XR 2,966,736 1/1961 Towner et a1 75138 XR JOHN H. MACK, Primary Examiner.
G. KAPLAN, Assistant Examiner.
Claims (1)
1. ALUMINUM ARTICLES HAVING AT LEAST ONE ANODIZED SURFACE FORMED OF AN ALLOY CONSISTING ESSENTIALLY OF BETWEEN 1% AND 4% OF METAL SELECTED FROM THE GROUP CONSISTING OF TI, ZR, NB, TA AD TH; BETWEEN 0.01 AND 0.1% OF A METAL SELECTED FROM THE GROUP CONSISTING OF TG, AU, PD, AND PT; AND THE BALANCE SUBSTANTIALLY ALL AL.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US485630A US3388050A (en) | 1965-09-07 | 1965-09-07 | Anodized aluminum alloy product |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US485630A US3388050A (en) | 1965-09-07 | 1965-09-07 | Anodized aluminum alloy product |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US3388050A true US3388050A (en) | 1968-06-11 |
Family
ID=23928872
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US485630A Expired - Lifetime US3388050A (en) | 1965-09-07 | 1965-09-07 | Anodized aluminum alloy product |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US3388050A (en) |
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4787943A (en) * | 1987-04-30 | 1988-11-29 | The United States Of America As Represented By The Secretary Of The Air Force | Dispersion strengthened aluminum-base alloy |
| US9359686B1 (en) | 2015-01-09 | 2016-06-07 | Apple Inc. | Processes to reduce interfacial enrichment of alloying elements under anodic oxide films and improve anodized appearance of heat treatable alloys |
| EP2534699A4 (en) * | 2010-02-08 | 2017-08-30 | FUJIFILM Corporation | Metal substrate with insulation layer and manufacturing method thereof, semiconductor device and manufacturing method thereof, solar cell and manufacturing method thereof, electronic circuit and manufacturing method thereof, and light-emitting element and manufacturing method thereof |
| US9869623B2 (en) | 2015-04-03 | 2018-01-16 | Apple Inc. | Process for evaluation of delamination-resistance of hard coatings on metal substrates |
| US9869030B2 (en) | 2014-08-29 | 2018-01-16 | Apple Inc. | Process to mitigate spallation of anodic oxide coatings from high strength substrate alloys |
| US9970080B2 (en) | 2015-09-24 | 2018-05-15 | Apple Inc. | Micro-alloying to mitigate the slight discoloration resulting from entrained metal in anodized aluminum surface finishes |
| US10174436B2 (en) | 2016-04-06 | 2019-01-08 | Apple Inc. | Process for enhanced corrosion protection of anodized aluminum |
| US10711363B2 (en) | 2015-09-24 | 2020-07-14 | Apple Inc. | Anodic oxide based composite coatings of augmented thermal expansivity to eliminate thermally induced crazing |
| US10760176B2 (en) | 2015-07-09 | 2020-09-01 | Apple Inc. | Process for reducing nickel leach rates for nickel acetate sealed anodic oxide coatings |
| US11242614B2 (en) | 2017-02-17 | 2022-02-08 | Apple Inc. | Oxide coatings for providing corrosion resistance on parts with edges and convex features |
| US11352708B2 (en) | 2016-08-10 | 2022-06-07 | Apple Inc. | Colored multilayer oxide coatings |
| US11549191B2 (en) | 2018-09-10 | 2023-01-10 | Apple Inc. | Corrosion resistance for anodized parts having convex surface features |
Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1912382A (en) * | 1931-09-05 | 1933-06-06 | Aluminum Co Of America | Method of making and casting aluminum alloys |
| US1946150A (en) * | 1931-05-15 | 1934-02-06 | Aluminum Co Of America | Coating of aluminum |
| US2050587A (en) * | 1934-02-17 | 1936-08-11 | Ruben Condenser Company | Electrolytic condenser |
| US2056604A (en) * | 1934-07-19 | 1936-10-06 | Degussa | Aluminum alloy |
| US2231373A (en) * | 1935-01-08 | 1941-02-11 | Firm Ematal Electrochemical Co | Coating of articles of aluminum or aluminum alloys |
| US2262967A (en) * | 1936-07-13 | 1941-11-18 | Firm Ematal Electrochemical Co | Process for the production of opaque enamellike, hard, and protective coatings on articles of aluminum and its alloys |
| US2272779A (en) * | 1939-12-27 | 1942-02-10 | Hartford Nat Bank & Trust Co | Flash lamp |
| US2798037A (en) * | 1953-05-13 | 1957-07-02 | Sprague Electric Co | Aluminum oxide films |
| US2966736A (en) * | 1958-03-27 | 1961-01-03 | Aluminum Co Of America | Aluminum base alloy powder product |
| US2966735A (en) * | 1958-03-27 | 1961-01-03 | Aluminum Co Of America | Aluminum base alloy powder product |
-
1965
- 1965-09-07 US US485630A patent/US3388050A/en not_active Expired - Lifetime
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1946150A (en) * | 1931-05-15 | 1934-02-06 | Aluminum Co Of America | Coating of aluminum |
| US1912382A (en) * | 1931-09-05 | 1933-06-06 | Aluminum Co Of America | Method of making and casting aluminum alloys |
| US2050587A (en) * | 1934-02-17 | 1936-08-11 | Ruben Condenser Company | Electrolytic condenser |
| US2056604A (en) * | 1934-07-19 | 1936-10-06 | Degussa | Aluminum alloy |
| US2231373A (en) * | 1935-01-08 | 1941-02-11 | Firm Ematal Electrochemical Co | Coating of articles of aluminum or aluminum alloys |
| US2260278A (en) * | 1935-01-08 | 1941-10-21 | Firm Ematal Electrochemical Co | Process for the production of opaque protective coatings on aluminum and its alloys |
| US2262967A (en) * | 1936-07-13 | 1941-11-18 | Firm Ematal Electrochemical Co | Process for the production of opaque enamellike, hard, and protective coatings on articles of aluminum and its alloys |
| US2272779A (en) * | 1939-12-27 | 1942-02-10 | Hartford Nat Bank & Trust Co | Flash lamp |
| US2798037A (en) * | 1953-05-13 | 1957-07-02 | Sprague Electric Co | Aluminum oxide films |
| US2966736A (en) * | 1958-03-27 | 1961-01-03 | Aluminum Co Of America | Aluminum base alloy powder product |
| US2966735A (en) * | 1958-03-27 | 1961-01-03 | Aluminum Co Of America | Aluminum base alloy powder product |
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4787943A (en) * | 1987-04-30 | 1988-11-29 | The United States Of America As Represented By The Secretary Of The Air Force | Dispersion strengthened aluminum-base alloy |
| EP2534699A4 (en) * | 2010-02-08 | 2017-08-30 | FUJIFILM Corporation | Metal substrate with insulation layer and manufacturing method thereof, semiconductor device and manufacturing method thereof, solar cell and manufacturing method thereof, electronic circuit and manufacturing method thereof, and light-emitting element and manufacturing method thereof |
| US9869030B2 (en) | 2014-08-29 | 2018-01-16 | Apple Inc. | Process to mitigate spallation of anodic oxide coatings from high strength substrate alloys |
| US11111594B2 (en) | 2015-01-09 | 2021-09-07 | Apple Inc. | Processes to reduce interfacial enrichment of alloying elements under anodic oxide films and improve anodized appearance of heat treatable alloys |
| US9359686B1 (en) | 2015-01-09 | 2016-06-07 | Apple Inc. | Processes to reduce interfacial enrichment of alloying elements under anodic oxide films and improve anodized appearance of heat treatable alloys |
| US9869623B2 (en) | 2015-04-03 | 2018-01-16 | Apple Inc. | Process for evaluation of delamination-resistance of hard coatings on metal substrates |
| US10760176B2 (en) | 2015-07-09 | 2020-09-01 | Apple Inc. | Process for reducing nickel leach rates for nickel acetate sealed anodic oxide coatings |
| US10711363B2 (en) | 2015-09-24 | 2020-07-14 | Apple Inc. | Anodic oxide based composite coatings of augmented thermal expansivity to eliminate thermally induced crazing |
| US9970080B2 (en) | 2015-09-24 | 2018-05-15 | Apple Inc. | Micro-alloying to mitigate the slight discoloration resulting from entrained metal in anodized aluminum surface finishes |
| US10174436B2 (en) | 2016-04-06 | 2019-01-08 | Apple Inc. | Process for enhanced corrosion protection of anodized aluminum |
| US11352708B2 (en) | 2016-08-10 | 2022-06-07 | Apple Inc. | Colored multilayer oxide coatings |
| US11242614B2 (en) | 2017-02-17 | 2022-02-08 | Apple Inc. | Oxide coatings for providing corrosion resistance on parts with edges and convex features |
| US11549191B2 (en) | 2018-09-10 | 2023-01-10 | Apple Inc. | Corrosion resistance for anodized parts having convex surface features |
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