Chromic Anodising

Compared with sulphuric acid anodising, the chromic acid anodising process gives relatively soft, thin coatings, normally of two to five microns thickness. These are used mainly for electrical insulation and general protection against corrosion under mild conditions. Unsealed coatings are used as a ‘key’ for paints and adhesives. It is light grey in colour, with a very silky texture.

The coating is on metal less than 250 microns thick, the process and resultant coating have less adverse effect upon the properties of the underlying metal