US1838633A - Coloring aluminum alloys - Google Patents
Coloring aluminum alloys Download PDFInfo
- Publication number
- US1838633A US1838633A US446791A US44679130A US1838633A US 1838633 A US1838633 A US 1838633A US 446791 A US446791 A US 446791A US 44679130 A US44679130 A US 44679130A US 1838633 A US1838633 A US 1838633A
- Authority
- US
- United States
- Prior art keywords
- aluminum alloys
- aluminum
- alloys
- coloring aluminum
- potassium
- 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
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
- C23C22/05—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 using aqueous solutions
- C23C22/60—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 using aqueous solutions using alkaline aqueous solutions with pH greater than 8
- C23C22/66—Treatment of aluminium or alloys based thereon
- C23C22/67—Treatment of aluminium or alloys based thereon with solutions containing hexavalent chromium
Definitions
- the subject of the invention is a process for the production of colored protective lay ers, grey or blackish for example, on alum num alloys, especially those containing s lia con, and/or zinc, and on articles made of such alloys.
- alloys wit protective coatings, which resist the action of weather and simi- 1o lar corrosive influences, by an oxidizing treatment with alkaline chromate solutions,
- the ordinary chromates or as dichromates for example potassium 1 dichromate
- the amount of the alkalies or substances with an alkaline reaction should be 10: 1.
- the chromates singly-for example as sodium or potassium 1 chromate or dichromate-or single alkalies-e such vas sodium or potassium carbonate, sodi- 50 um or potassium hydroxide, and the like at least 1.5% (preferably about 2% or over) by weight, calculated as, orequivalent to,
- the alloys suitable for treatment comprise all the known aluminum alloys, those containing silicon and zincv in particular; and preferably, for example, the aluminum silicon alloys known under the registered trademarks, Silumin and Alpax; also the al-. loys containing, for example, manganese, antimony, molybdenum, copper, silver, tin, zinc, tungsten and the like. It is possible by suitably varying the alloying components, to influence the shade of the resulting-protective layer as desired, within certain limits. It has also been ascertained that similar effects can also be obtained by the addition of very small quantities of the salts of certain metals,-such solutions. I
- Ewample l I An article composed of an alloy containing about 87% of aluminum and 13% of silicon is first subjected to mechanical treatment with a revolving wire brush, and is then dipped into an aqueous solution,heated to about 90 G.containing 1 grm. of potassium dichromate and 15 grms. of sodium carbonate (Na CO or the equivalent quantity of caustic soda, per litre. The formation of the superficial layer will be complete in about two minutes, whereupon the article is taken out of the bath, well washed with water and dried in the usual manner. protective layer formed thereon is dark grey in color, witha high lustre, and displays high powers of resistance to moisture, neutral saline solutions and the like.
- Ewample II An article composed of an alloy containing about 90% of aluminum and 10% of zinc, is first treated mechanically, for example, by sandblasting, and is then dipped mto an aqueous solution, at about 90 C. con- T taining 2 grms. of potassium dichromate and loys which contains a small amount of a soluble dichromate salt, not exceeding -.02% of the weight of the solution in company with at least about 1.5% of alkali carbonate or by. droxide. v
Landscapes
- 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 2 9, 1931 UNITED STATES ALADAR PACZ, 0F GLEVELAN'D, OHIO COLORING ALUMINUM ALLOYS Ito Drawing. Application flied April 23, 1930, Serial No. 446,791, and in Germany August 10, 1929.
The subject of the invention is a process for the production of colored protective lay ers, grey or blackish for example, on alum num alloys, especially those containing s lia con, and/or zinc, and on articles made of such alloys.
it is well known to provide aluminum and aluminum. alloys wit protective coatings, which resist the action of weather and simi- 1o lar corrosive influences, by an oxidizing treatment with alkaline chromate solutions,
um chromate), relatively larger amounts of 25 substances with an alkaline reaction, such as sodium carbonate, caustic soda or the like.
in the form oi the ordinary chromates or as dichromates (for example potassium 1 dichromate) is below about 0.25% (and preterably below 0.2%) by weight, calculated as I potassium dichromates, of the treating solution. The amount of the alkalies or substances with an alkaline reaction, should be 10: 1. Instead of employing the chromates singly-for example as sodium or potassium 1 chromate or dichromate-or single alkalies-e such vas sodium or potassium carbonate, sodi- 50 um or potassium hydroxide, and the like at least 1.5% (preferably about 2% or over) by weight, calculated as, orequivalent to,
' least 5: 1, but is preferably not below 8: 1 to In the process of the present invention, in contradistinction to the known processes,
neither an oxidic nor a metallic coating is formed on the articles treated, but, on the contrary, by virtue of the action of the relatively largeamount of alkali contained in the solutions, aluminum is dissolved out of the metallic surface to a certain depth, thereby exposing and coloring the alloying components, such as silicon, manganese and the like, whilst-according to the experience of the applicantthe very small amount of chromate present serves to distribute the said alloying components exposed by the dissolving out of the aluminumover the residual surface and to fix same thereto. The process when performed in the manner hereinbefore described, and preferably at elevated temperatures, such as near the boiling point of the liquid employed in the treatment, occupies only an exceedingly short time, so that, in most cases, handsomely colored and durable protective layers can be obtained in a few (e. g. 2) minutes, Whereas, with the other, The amount of chromates employed, Whether kn own processes, the time required is far longer and may extend to several hours.
The alloys suitable for treatment comprise all the known aluminum alloys, those containing silicon and zincv in particular; and preferably, for example, the aluminum silicon alloys known under the registered trademarks, Silumin and Alpax; also the al-. loys containing, for example, manganese, antimony, molybdenum, copper, silver, tin, zinc, tungsten and the like. It is possible by suitably varying the alloying components, to influence the shade of the resulting-protective layer as desired, within certain limits. It has also been ascertained that similar effects can also be obtained by the addition of very small quantities of the salts of certain metals,-such solutions. I
In general, it has been found desirable,
as those enumerated aboveto thetreating especially in the treatment of aluminum- 7 alloy castings, to subject these articles to a preliminary mechanical treatment of known kind, such as sandblasting, scrubbing with wire brushes, and the like, which will remove any superficial film of oxide present and facilitate the action of the alkaline solution on the clean metallic surface thereby exposed.
Ewample l I An article composed of an alloy containing about 87% of aluminum and 13% of silicon is first subjected to mechanical treatment with a revolving wire brush, and is then dipped into an aqueous solution,heated to about 90 G.containing 1 grm. of potassium dichromate and 15 grms. of sodium carbonate (Na CO or the equivalent quantity of caustic soda, per litre. The formation of the superficial layer will be complete in about two minutes, whereupon the article is taken out of the bath, well washed with water and dried in the usual manner. protective layer formed thereon is dark grey in color, witha high lustre, and displays high powers of resistance to moisture, neutral saline solutions and the like.
Ewample II An article composed of an alloy containing about 90% of aluminum and 10% of zinc, is first treated mechanically, for example, by sandblasting, and is then dipped mto an aqueous solution, at about 90 C. con- T taining 2 grms. of potassium dichromate and loys which contains a small amount of a soluble dichromate salt, not exceeding -.02% of the weight of the solution in company with at least about 1.5% of alkali carbonate or by. droxide. v
2. A dipping solution as set forth in claim 1 in which the ratio of alkali to chromate is greater than five to one.
In testimony whereof I hereunto afiix my signature.
A] iADAR PACZ.
The
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE1838633X | 1929-08-10 |
Publications (1)
Publication Number | Publication Date |
---|---|
US1838633A true US1838633A (en) | 1931-12-29 |
Family
ID=7745475
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US446791A Expired - Lifetime US1838633A (en) | 1929-08-10 | 1930-04-23 | Coloring aluminum alloys |
Country Status (1)
Country | Link |
---|---|
US (1) | US1838633A (en) |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2460897A (en) * | 1944-09-14 | 1949-02-08 | Enthone | Rendering aluminum and aluminum alloy surfaces corrosion resistant |
US2554256A (en) * | 1948-05-15 | 1951-05-22 | Westinghouse Electric Corp | Process for treating aluminum to provide selective coloration of portions thereof |
US2684922A (en) * | 1950-05-06 | 1954-07-27 | Reynolds Metals Co | Method of making planographic printing sheets |
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 |
US2987426A (en) * | 1957-01-30 | 1961-06-06 | Ici Ltd | Alkali baths for metal treatment |
US3725137A (en) * | 1971-03-10 | 1973-04-03 | Reactor Ct Nl | Method for the blackening of aluminum alloys |
-
1930
- 1930-04-23 US US446791A patent/US1838633A/en not_active Expired - Lifetime
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2460897A (en) * | 1944-09-14 | 1949-02-08 | Enthone | Rendering aluminum and aluminum alloy surfaces corrosion resistant |
US2554256A (en) * | 1948-05-15 | 1951-05-22 | Westinghouse Electric Corp | Process for treating aluminum to provide selective coloration of portions thereof |
US2684922A (en) * | 1950-05-06 | 1954-07-27 | Reynolds Metals Co | Method of making planographic printing sheets |
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 |
US2987426A (en) * | 1957-01-30 | 1961-06-06 | Ici Ltd | Alkali baths for metal treatment |
US3725137A (en) * | 1971-03-10 | 1973-04-03 | Reactor Ct Nl | Method for the blackening of aluminum alloys |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US2364993A (en) | Process for blackening copper or copper alloy surfaces | |
US2106904A (en) | Coating malleable non-noble heavy metals | |
US2647865A (en) | Brightening aluminum and aluminum alloy surfaces | |
US2008733A (en) | Treatment of coatings | |
US1710743A (en) | Surface treating aluminum articles | |
US1838633A (en) | Coloring aluminum alloys | |
US3852124A (en) | Duplex sealing process | |
US2137988A (en) | Adherent aluminum compound | |
US2030476A (en) | Method of producing mirrors | |
US2493934A (en) | Production of protective coatings on aluminum and alloys thereof | |
US1965269A (en) | Method of coloring aluminum | |
US1946153A (en) | Protecting aluminum from corrosion | |
US1957354A (en) | Process of protecting light metals against corrosion | |
US1798218A (en) | Coating and coloring metals | |
US2431728A (en) | Treatment of ferrous metals to improve resistance to rusting | |
Caley | Coatings and incrustations on lead objects from the Agora and the method used for their removal | |
US2382865A (en) | Bright dip | |
US2247580A (en) | Process of producing black-colored aluminum or aluminum alloys | |
US2440837A (en) | Metal cleaning composition | |
US1995225A (en) | Method of preventing tarnishing of metal articles | |
US2322205A (en) | Method of treating magnesium and its alloys | |
US3620939A (en) | Coating for magnesium and its alloys and method of applying | |
US2066180A (en) | Production of protective coating on aluminum and noncuprous alloys thereof | |
US2520475A (en) | Process for the chemical oxidation of aluminum and alloys thereof | |
US1946148A (en) | Method of coating |