METHOD OF MANUFACTURING AN INTERFERENCE COATING

Abstract

A method of manufacturing an interference coating on the surface of an aluminum alloy or aluminum alloys product comprising anodizing and electrochemical dyeing with use of alternating current consisting in that, the electrolyte used during electrochemical dyeing comprises copper (II) sulfate (IV) in an amount from 1 to 100 g/L, boric acid in the amount of 1 to 40 g/L and tartaric acid in the amount of 0.1 to 20 g/L.

Claims

1. A method of manufacturing an interference coating on the surface of an aluminum alloy or aluminum alloys product comprising anodizing and electrochemical dyeing with use of alternating current, characterized in that, the electrolyte used during electrochemical dyeing comprises copper (II) sulfate (VI) in an amount from 1 to 100 g/L, boric acid in the amount of 1 to 40 g/L and tartaric acid in the amount of 0.1 to 20 g/L.

2. The method according to claim 1, characterized in that, dyeing is conducted under continuous stirring of electrolyte.

3. The method according to claim 1, characterized in that, the time of dyeing is longer than 10 seconds.

4. The method according to claim 1, characterized in that, dyeing is conducted at a temperature 5-40° C.

5. The method according to claim 1, characterized in that, dyeing is conducted with use of alternating current having voltage in range 0.5-50 V.

6. The method according to claim 1, characterized in that, anodizing is conducted in the solution of sulfuric acid (VI) having concentration of 50-500 g/L with the addition of aluminum ions in the amount of 0-100 g/L.

7. The method according to claim 1, characterized in that, anodizing is conducted at a current density of 0.1-5 A/dm.sup.2.

8. The method according to claim 1, characterized in that, anodizing is conducted for 10-3600 seconds.

9. The method according to claim 1, characterized in that, the product is sealed after dyeing.

10. The method according to claim 9, characterized in that, sealing is conducted by hot or cold hydrothermal or vapor deposition methods.

11. The method according to claim 10, characterized in that, sealing is conducted by vapor deposition method using atomic layer deposition.

Description

[0024] The subject of the invention is disclosed at the drawings, where FIG. 1 illustrates a block diagram of the interference coatings manufacturing process, FIG. 2—cross-section of the aluminum product showing the structure of the coating with light interference.

EXAMPLES

Example 1

[0025] After degreasing and etching the surface, the aluminum product is anodized in an aqueous solution of sulfuric acid (VI) having concentration of 150 g/L with the addition of aluminum ions at the level of 1.1 g/L at a temperature of 18° C., under direct current conditions with a current density of 1.1 A/dm.sup.2. An aluminum sheet with a surface equal to or greater than that of the aluminum product may be used as the cathode. The anodizing time was 200 seconds. After completing the anodizing process, the product should be rinsed in deionized water, and after draining off the excess, next step can be started. Electrochemical dyeing is performed using an alternating current of 8 V in an electrolyte containing 15 g/L of copper (II) sulfate (VI), 20 g/L of boric acid and 1 g/L of tartaric acid. During the whole process, the electrolyte temperature is 18° C. A stainless steel counter electrode has a working surface equal to or greater than that of the aluminum product. The electrolyte is constantly stirred and the dyeing time is 120 seconds. After the end of the process, the aluminum product is rinsed in deionized water and then dried.

[0026] The block diagram of the interference coating manufacturing process is shown in FIG. 1, where the numbers represent [0027] 1—the process of washing and etching the aluminum product; [0028] 2, 4, 6, 9—rinsing process with deionized water; [0029] 3—anodizing of the aluminum product; [0030] 5—dyeing with alternating current (AC); [0031] 7, 10—drying the finished product; [0032] 8—sealing the oxide coating on the aluminum product.

[0033] The dashed line indicates the optional sealing path for the coating of the aluminum product.

Example 2

[0034] Manufacturing of an interference coating according to the guidelines described in example 1, followed by a hydrothermal heat seal. The block diagram of the interference coating manufacturing process is shown in FIG. 1.

Example 3

[0035] Manufacturing of an interference coating according to the guidelines described in example 1, followed by cold sealing. The block diagram of the interference coating manufacturing process is shown in FIG. 1.

Example 4

[0036] Manufacturing of an interference coating according to the guidelines described in example 1, followed by, and then performing the seal using vapor deposition method e.g. atomic layer deposition method. The block diagram of the interference coating manufacturing process is shown in FIG. 1.

Example 5

[0037] After degreasing and etching the surface, the aluminum product is anodized in an aqueous solution of sulfuric acid (VI) having concentration of 145 g/L with the addition of aluminum ions at the level of 1 g/L at a temperature of 11° C., under direct current conditions with a current density of 1.2 A/dm.sup.2. An aluminum sheet with a surface equal to or greater than that of the aluminum product may be used as the cathode. The anodizing time was 250 seconds. After completing the anodizing process, the product should be rinsed in deionized water, and after draining off the excess, next step can be started. Electrochemical dyeing is performed using an alternating current of 12 V in an electrolyte containing 13 g/L of copper (II) sulfate (VI), 22 g/L of boric acid and 1.6 g/L of tartaric acid. During the whole process, the electrolyte temperature is 22° C. A stainless steel counter electrode has a working surface equal to or greater than that of the aluminum product. The electrolyte is constantly stirred and the dyeing time is 160 seconds. After the end of the process, the aluminum product is rinsed in deionized water and then dried. The block diagram of the interference coating manufacturing process is shown in FIG. 1.

Example 6

[0038] After degreasing and etching the surface, the aluminum product is anodized in an aqueous solution of sulfuric acid (VI) having concentration of 150 g/L with the addition of aluminum ions at the level of 1.1 g/L at a temperature of 18° C., under direct current conditions with a current density of 1.1 A/dm.sup.2. An aluminum sheet with a surface equal to or greater than that of the aluminum product may be used as the cathode. The anodizing time was 200 seconds. After completing the anodizing process, the product should be rinsed in deionized water, and after draining off the excess, next step can be started. Electrochemical dyeing is performed using an alternating current of 8 V in an electrolyte containing 15 g/L of copper (II) sulfate (VI), 22 g/L of boric acid and 1.6 g/L of tartaric acid. During the whole process, the electrolyte temperature is 18° C. A stainless steel counter electrode has a working surface equal to or greater than that of the aluminum product. The electrolyte is constantly stirred and the dyeing time is 120 seconds. After the end of the process, the aluminum product is rinsed in deionized water and then dried. The block diagram of the interference coating manufacturing process is shown in FIG. 1.

Example 7

[0039] After degreasing and etching the surface, the aluminum product is anodized in an aqueous solution of sulfuric acid (VI) having concentration of 120 g/l with the addition of aluminum ions at the level of 1 g/L at a temperature of 18° C., under direct current conditions with a current density of 1.1 A/dm.sup.2. An aluminum sheet with a surface equal to or greater than that of the aluminum product may be used as the cathode. The anodizing time was 200 seconds. After completing the anodizing process, the product should be rinsed in deionized water, and after draining off the excess, next step can be started. Electrochemical dyeing is performed using an alternating current of 8 V in an electrolyte containing 15 g/L of copper (II) sulfate (VI), 20 g/L of boric acid and 1 g/L of tartaric acid. During the process, the electrolyte temperature is 18° C. A stainless steel counter electrode has a working surface equal to or greater than that of the aluminum product. The electrolyte is constantly stirred and the dyeing time is 120 seconds. After the end of the process, the aluminum product is rinsed in deionized water and then dried. The block diagram of the interference coating manufacturing process is shown in FIG. 1.

Example 8

[0040] After degreasing and etching the surface, the aluminum product is anodized in an aqueous solution of sulfuric acid (VI) having concentration of 150 g/L with the addition of aluminum ions at the level of 1 g/L at a temperature of 20° C., under direct current conditions with a current density of 1.1 A/dm.sup.2. An aluminum sheet with a surface equal to or greater than that of the aluminum product may be used as the cathode. The anodizing time was 200 seconds. After completing the anodizing process, the product should be rinsed in deionized water, and after draining off the excess, next step can be started. Electrochemical dyeing is performed using an alternating current of 8 V in an electrolyte containing 15 g/L of copper (II) sulfate (VI), 20 g/L of boric acid and 1 g/L of tartaric acid. During the whole process, the electrolyte temperature is 22° C. A stainless steel counter electrode has a working surface equal to or greater than that of the aluminum product. The electrolyte is constantly stirred and the dyeing time is 120 seconds. After the end of the process, the aluminum product is rinsed in deionized water and then dried. The block diagram of the interference coating manufacturing process is shown in FIG. 1.

Example 9

[0041] After degreasing and etching the surface, the aluminum product is anodized in an aqueous solution of sulfuric acid (VI) having concentration of 120 g/l with the addition of aluminum ions at the level of 1 g/L at a temperature of 21° C., under direct current conditions with a current density of 1.1 A/dm.sup.2. An aluminum sheet with a surface equal to or greater than that of the aluminum product may be used as the cathode. The anodizing time was 250 seconds. After completing the anodizing process, the product should be rinsed in deionized water, and after draining off the excess, next step can be started. Electrochemical dyeing is performed using an alternating current of 8 V in an electrolyte containing 15 g/L of copper (II) sulfate (VI), 20 g/L of boric acid and 1 g/L of tartaric acid. During the whole process, the electrolyte temperature is 25° C. A stainless steel counter electrode has a working surface equal to or greater than that of the aluminum product. The electrolyte is constantly stirred and the dyeing time is 100 seconds. After the end of the process, the aluminum product is rinsed in deionized water and then dried. The block diagram of the interference coating manufacturing process is shown in FIG. 1.

Example 10

[0042] The aluminum product manufactured by the method according to the invention has an interference coating. FIG. 2 shows a cross-section of such a product showing the structure of a coating in which light interference occurs, where the individual numbers represent: [0043] 11—area of precipitated copper; [0044] 12—pore in the structure of the oxide layer on aluminum; [0045] 13—an oxide layer on aluminum resulting from the anodizing process; [0046] 14—the wall of the aluminum product; [0047] A—ray of light reflected from the oxide layer; [0048] B—a ray of light reflected from the surface of copper precipitation; [0049] C—a ray of light reflected from the bottom of the porous structure; [0050] d—the thickness of the oxide layer on the aluminum.