Anodizing of Aluminum

Anodizing

By nature Aluminum has a protecting oxide layer on its surface, which gives the Aluminum surface a matte and white look. The oxide layer makes the surface very resistant to corrosion (does not rust). Different types of surface treatment can enhance this property further.

A very important factor in relation to prolonging the life of the product and to the maintenance in its expected lifetime. Together with lacquering, anodizing is the most commonly used surface treatment for protecting and decorative purposes on Aluminum.

Anodizing has been known since the beginning of the 1920s where Bengough-Stuart patented the Chrome acid anodizing. The natural oxide layer is made thicker through the anodizing process so that improved corrosion and wear properties are obtained. During the process a porous oxide layer is formed giving way to colouring in a number of beautiful colours.

Anodizing in sulphuric acid is the most commonly used and most environmentally safe process, because the protecting layer is made up of the same type of Aluminum oxide that was produced at the electrolytic process.



The most beautiful aluminum surface, etched and anodized by the Danish Designer, Bess Kristoffersen, www.besskristoffersen.dk