Coating a metal with a protective film by electrolytic action.

Anodizing refers to the surface treatment of aluminum to prevent oxidation. It is a “deplating” process, since. the work itself becomes the anode in the plating bath and metal is thrown off rather than put on. Nascent oxygen is released at the anode. This immediately attacks the metal surface and forms an extremely hard oxide film. The anodizing treatment is widely used in the aircraft industry, and to treat aluminum automobile pistons.

X