Three Reasons for the Inconsistent Color of Aluminum Profiles-Aluminum Profiles Supplier

As we all know, the anode oxide film of aluminum profiles is composed of a large number of hexagonal cells vertically on the metal surface. Each cell center has a membrane hole and has a strong adsorption force. Oxide products are soaked in the dye solution, the dye molecules diffuse to the membrane hole, forming a covalent and ion bond with the oxide film, which is difficult to separate. The combination is reversible, and the suction occurs under certain conditions.

Therefore, after dyeing, a hole should be sealed and the dye is fixed in the hole of the membrane layer to improve the corrosion resistance and abrasion resistance of the oxide film. During the entire oxidation staining process, poor dyeing is common due to oxidation process. The thickness and pore rate of the uniform oxide film are the prerequisite and foundation of the uniform color of the dyeing. In order to obtain a uniform oxide film, it is very important to ensure sufficient circulating cooling ability and good conductivity.

In addition, it is the stability of the oxidation process. When the concentration of sulfuric acid is controlled at 180-200g/L, a slightly higher sulfuric acid concentration can accelerate the dissolving response of the oxide film, which is conducive to the expansion of the hole and is more likely to dye; when the aluminum ion concentration is less than 5g/L, the adsorption capacity of the oxide film is reduced, and the absorption capacity of the oxide film is reduced. Affects color speed. When the aluminum ion concentration is greater than 15g/L, it will affect the uniformity of the oxide film and prone to irregular oxide film. When the oxidation temperature is about 20, the oxidation bath temperature has a significant impact on dyeing.

If the temperature is too high, the oxide film is loose and easy to powder, which is not conducive to dyeing control. The temperature difference between the oxidation slot should be within 2. The current density is controlled between 120-180A/m2.

If the current density is too high and the membrane is thick, the electrolytic time of aluminum products in the electrolyte should be shortened to reduce the dissolution of the oxide film in the solution, dense the membrane hole, and extend the dyeing time. At the same time, the paint film is easy to powder.

If the thickness of the paint film is too low, the dyeing is uneven, and the dyeing requires the thickness of the oxide film above 10 m. At the same time, when dark (such as black) is needed, due to the lack of membrane thickness, the dye deposition volume is limited, and the required shades cannot be met. In short, as a pre -treatment of dyeing, anode oxidation is the basis of dyeing. The problem of anode oxidation is difficult or invisible before dyeing.

Once staining, we can clearly see the phenomenon of uneven color. At this time, production workers often attribute problems to the abnormal dyeing, and ignored the reason for the reason for the reason during the oxidation process. These errors are often in your first contact with oxidation staining.