Anodized film with special appearance requirements such as smooth surface, uniform bright, requires chemical, or electrochemical polishing in advance. Like the mechanical polishing, chemical, and electrochemical polishing are indispensable surface pretreatment technologies for the preparation of high-precision bright aluminum surface treatment. In some cases, it can be used as the final finishing method.
Mechanical polishing is a physical method to cut or grind the aluminum surface to achieve plastic shape change, level the convex portion, lower the surface roughness and produce a smooth or gloss surface. Chemical polishing is a chemical corrosion under special conditions. It controls the selective dissolution of the aluminum surface so that the convex portion is more seriously dissolved than the concave portion and thus finally makes the surface smooth and shiny. Electrochemical polishing is also known as electrolytic polishing. Its working principle is similar to chemical polishing as it also relies on the selective dissolution on the convex portion in the surface to produce a flat and smooth surface.
