CHEMICAL CONVERSION COATINGS

Chemical Conversion Coatings are also known as “Chem Film” processes. At present two type of “Chem Films” are provided. Chem Films with hexavalent chrome and chem films with trivalent chrome. These coatings are functional and offer some corrosion protection. They are used as a pre-process to increase adhesion before painting operation and in electrical application for low resistance contacts.

Hexavalent Chem Films vary from dark gold color to clear. These coating are Non-ROHS processes.

Trivalent Chem Films vary from clear to a light blue color. The coatings meet the ROHS requirement. These chromate conversion coatings are very thin amorphous inorganic films formed by contacting a metallic surface with an aqueous solution whose mail film-forming agent is a soluble chromate species.
Chromate conversion coatings form spontaneously without application of current or voltage and are applied most commonly on aluminum.