Anodizing, or anodized oxidation, is an electrical process by which a chemically stable oxidized layer is created. The layer is hard, porous, transparent, electronically non-conducting, and is a part of the aluminum, so that it cannot peel away or spall. The oxidized layer can be colorized once it is created. The thickness of the layers can be selected. For use outdoors, a 20 micron thick layer is recommended.

The tone of the colour when anodizing is dependent upon the original material and can differ depending upon the manufacturing process. Minor differences in colour hue are non-avoidable. Due of this, tolerance samples are recommended for the desired colour hue.

Surface colouring is a result of the surface preparation as well as the dyeing process.

Surface Preparation

  • E0 - technically anodized
  • E1 - sanded and anodized
  • E2 - brushed and anodized
  • E3 - polished and anodized
  • E4 - sanded, brushed and anodized
  • E5 - sanded, polished and anodized
  • E6 - chemically treated and anodized
Dyeing Process  Appearance
Natural Colouring (C0) / without dyeing (EV1) a clear, transparent, anodized layer, displays the natural, silver shine of aluminum, which is also classified as ‘natural’ (colourless).
Organic colours Champagne/Light Gold (EV2), brass (EV3), Black (EV6)
Electrolytic colours Nickel Silver (C31), Light Bronze (C32), Bronze (C33), Dark Bronze (C34), Black (C35)
Combined Colours (C61 to C65)* Diverse tones such as: Blue, Red, Turquoise, Green and Orange. Combination of electrolytic bronze colors with non-fading organic dyes*

* mostly for small parts (ca. 300 mm)

Example of a common surface indicator: E6EV1 or E6C0

Recommendation for practical application:
Aluminum alloys should be used for anodized parts that require a decorative appearance. Possible variations in color anodized aluminum parts must be glazed in adequate sizes by means of color standard values using original application material. These colorization standard values are determined for the execution of the order. While anodizing, the location and the permissibility of contact points should be observed.

Further information concerning Aluminium Louvres