Anodized aluminum production process

Anodized aluminum refers to a layer of dense aluminum oxide coated on the surface of aluminum and aluminum alloys. In order to prevent further oxidation, its chemical properties are the same as aluminum oxide. But unlike ordinary oxide films, anodized aluminum can be dyed with electrolytic coloring.
1. Mechanical polishing;
2. Chemical treatment to remove copper components on the surface of some alloys;
3. Clean and remove oil (for parts that have been anodized, if they need to be re-anodized, use alkali or special agent to remove the original anodized surface layer);
4. Put it into dilute sulfuric acid as an anode to energize to generate a surface oxide layer (which is porous and is a white translucent film);
5. Dyeing;
6. Fixing (heat or chromate solution to seal pores in surface oxide).