Finishing: Chromate Conversion Coating
What is Chromate Conversion Coating?
Chromate Conversion coating, also known as “chemical film”, uses a chromic acid bath to produce a thin protective film on aluminum or aluminum alloys. These coatings are highly corrosion resistant and provide an easy-to-paint surface. These coatings are often applied to galvanized parts in order to protect the zinc coating from white corrosion increasing the part’s durability. Chromate coatings are gelatinous when applied, but harden with age or heat, however, heating above 70 °C can damage the coating and is not recommended. Chromate conversion coatings can typically be recognized by their iridescent, greenish-yellow color, however, depending on the metal, colors can vary from yellow to black which is usually thicker and more corrosion resistant.