Anodising
An electrolytic passivation process used to increase the thickness of the natural oxide layer on the surface of metal parts. Anodizing increases resistance to corrosion and wear, and provides better adhesion for paint primers and glues than bare metal. Anodic films can also be used for a number of cosmetic effects, either with thick porous coatings that can absorb dyes or with thin transparent coatings that add interference effects to reflected light. Anodising is one of the more environmentally friendly metal finishing processes.