What is the role of anodizing aluminum coils?
Aluminum coils and aluminum alloys will oxidize in the air. Of course, the oxide film produced on the surface of the aluminum has an amorphous structure, which will cause the surface of the aluminum metal to lose its original gloss, although this layer of pure natural oxide film will make the surface of the aluminum metal slightly Passivation, but it is very thin, about 4-5nm, and has large porosity and poor physical properties. It cannot effectively prevent further corrosion of aluminum metal by various substances in the air.
For example, 1050 aluminum coil is treated by anodic oxidation, which can make the surface of aluminum and aluminum alloy get a high-density film layer (from tens of microns to hundreds of microns) that is much thicker than the natural oxide film.
This layer of man-made oxide film is closed again, and the oxide film with no crystal structure is converted into an oxide film of modified epoxy resin, and the porosity is also closed, so that the gloss of the metal surface will not change for a long time, and the anti-corrosion properties , the impact toughness is gradually improved, and the appearance of decorative art can also be obtained after coloring. Because aluminum and metal products have many characteristics after anodizing, the aluminum anodizing process is widely used in the surface treatment of metal aluminum.