After the anodizing processing of aluminum alloy, a layer of anti-oxidation, anti-rust, anti-corrosion and wear-resistant oxide film will be formed. Moreover, the performance of this oxide film in the natural ecological environment is very stable, which can protect the surface safety of aluminum alloy products. Moreover, the outer layer of the anodic oxide film of aluminium is porous and can easily adsorb dyes and colored substances, thus allowing for dyeing and enhancing its decorative effect. After being sealed with hot water, high-temperature steam or nickel salts, the oxide film can further enhance its corrosion resistance and wear resistance.
At present, the defects of aluminum profile coloring can be roughly classified into the following situations: light color, color difference, inability to dye, white spots, exposed white, dyeing mottled, color escape, etc. How can such problems be solved to ensure that the color difference of each batch of products remains consistent?
This requires our enterprise technicians to conduct research and take precautions when carrying out electrolytic coloring surface treatment on profiles. Now let's explain the causes and treatment methods for the light color and color difference of aluminum profiles during anodizing:
The thickness of the oxide scale film is uneven. The possible cause is the uneven temperature and concentration of the anodizing bath solution. At this time, the bath solution should be stirred with compressed air to solve such problems.
2. Uneven temperature or concentration of the dyeing solution. Introduce the stirring process and increase the number of stirring times at the same time.
3. The dyeing speed is too fast. The bottom of the workpiece first enters the dyeing solution and then leaves it, so the bottom is prone to deep dyeing. The solution is to dilute the dye and appropriately extend the dyeing time.
4. Poor electrical conductivity. It might be caused by loose hangers. Make sure to hang them tightly to avoid such problems.
5. The dye is too dilute. You can add dye to increase the concentration.
6. The temperature of the dyeing solution is too low. The dyeing solution can be heated to below 60℃.
7. Improper dissolution of dyes or the presence of insoluble dyes floating can easily lead to color differences. The solution is to improve the dye dissolution.
In addition, it should be noted that the temperature during the anodizing process of aluminum profiles has a significant impact on the performance of the oxide film: if the temperature is too high, the wear resistance and corrosion resistance of the oxide film will decrease, and it will be difficult to form a film. When the temperature is too low, the transparency of the film layer decreases, the coloring performance is poor, the brittleness increases, and it is prone to cracking.
