In the actual process, there are more anodic oxidations for aluminum alloys, which can be applied in daily life. The characteristics of this process can produce a hard protective layer on the surface of aluminum parts, which can be used to produce kitchen utensils and other daily necessities. However, the anodizing effect of cast aluminum is not good, the surface is not good, and it can only be black. Aluminum alloy profiles are better.
In the past ten years, aluminum plate oxidation and coloring technology has developed rapidly. Many factories have adopted new technology and have accumulated rich experience in actual production. There are many oxidation process methods for aluminum and its alloys that have been mature and under development, and suitable processes can be selected according to actual production needs.
Before choosing the oxidation process, you should understand the material of aluminum or aluminum alloy, because the quality of the material and the difference in the composition will directly affect the quality of the aluminum product after anodization. On this point, if there are bubbles, scratches, peeling, roughness and other defects on the aluminum surface, all defects will still be revealed after anodizing. The alloy composition also has a direct effect on the surface appearance after anodization. For example, an aluminum alloy containing 1 to 2% manganese will be brownish-blue after oxidation. With the increase of the manganese content in the aluminum material, the surface color after oxidation will change from brownish-blue to dark brown. Aluminum alloy with 0.6 to 1.5% silicon content is gray after oxidation, and white gray when silicon content is 3 to 6%. Zinc-containing products are opalescent, chromium-containing products have an uneven tone of golden to gray, and nickel-containing products are light yellow. Generally speaking, only aluminum with magnesium and titanium content greater than 5% contains gold, and after oxidation, a colorless, transparent, bright and clean appearance can be obtained.
After choosing aluminum and aluminum alloy materials, it is natural to consider choosing a suitable anodizing process. At present, the sulfuric acid oxidation method, oxalic acid oxidation method and chromic acid oxidation method widely used in our country have been introduced in detail in manuals and books, so there is no need to go into details.
