Iridescence phenomenon on Anodized Aluminum

The phenomenon of Iridescense occurs on surfaces exposed to the aggresive weather and is the result of an optical interference color.

The phenomenon is very evident on surfaces, anodized and electrolytic colored to dark shades, while it is much less found on natural color anodized surfaces.

In the photo below you can see the appearance of a surface of anodized aluminum and black electrolytic coloring which has formed a multicolored covering the color black.

Causes
The origins of this defect are not well known. This is a very light surface deterioration that can be correlated with the presence of particular pollutants in industrial environments, especially fluorides.

Elimination
The iridescence can easily be eliminated with the use of slightly abrasive products, already on the market. These products are specially formulated for cleaning anodized surfaces. Every cleaning product should be tested before their use in an area, which is not visible, to check their efficiency.

The use of water alone does not allow the elimination of the defect.

This content is courtesy of QUALITAL

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