In order to improve the corrosion resistance of aluminium sheet surface, aluminium profiles are extruded and treated by various surface treatment methods. The commonly used surface treatment methods of aluminium alloy are anodizing once, electrophoretic coating twice and powder spraying three times. These three methods have different principles and advantages and disadvantages. Here is a brief analysis of their advantages and disadvantages.
The shortcomings of three surface treatment methods for aluminium coil:
1. Electrophoretic coating: If electrophoretic coating does not strictly meet various technological requirements, such as long baking time, contamination of the tank, unqualified components of the tank, etc. Aluminum profiles have surface defects such as rough surface, foaming, pinhole or shrinkage, varnish coloring, low gloss, uneven paint film and cracks on the profile surface.
Aluminum coil manufacturer
2. Anodic oxidation: the oxide film is easy to mix with impurities and yellowing; the material is easy to stick together, so that the oxide surface is not uniform, forming a rainbow color, resulting in poor appearance of the product; the surface and cold bed are easy to form black. K or white; too high temperature of electrolyte or too long electrolysis time lead to surface deformation of aluminium profile. White opaque powder; in the oxidation process, if the profile falls, it is easy to cause short circuit. In the process of alkali corrosion, if the sulfuric acid concentration is not well controlled, the corrosion resistance of profile surface will be reduced. The surface of the oxide film is also prone to oxidation. Grey, black or appearance quality problems.
3. Powder coatings: If raw materials are not of good quality and mixed with dust or impurities, particles will be generated on the surface of profiles; if compressed air is not clean, it will also cause shrinkage defects on the surface of aluminium profiles when mixed with oil or water; improper matching will affect the physical and chemical properties of aluminium products, such as hardness, impact resistance and bending resistance; It also leads to powdery and yellowing on the surface of the profile with poor appearance.
Above is the related content that the aluminium coil manufacturer sorted out for you. For more information, please visit the website: .