Chromate
Conversion Coating (Chem-Film) Definition: Chromate conversion, also known as chemical film, alodine or iridite, offers increased corrosion protection on aluminum. It is inexpensive, electrically conductive and is often used as a pre-treatment for paint and adhesives. Chromate can be used as a standalone finish or as a post treatment over other metal plating finishes.
Mil-C-5541 or Mil-DTL-5541 or Mil-DTL-81706 Classifications Type I-Compositions containing hexavalent chromium Type II-Compositions containing no hexavalent chromium Class 1A-For maximum protection against corrosion, painted or unpainted Class 3-For protection against corrosion where low electrical resistance is required ASTM B449-93 (re-approved 2015) Classifications KEY: Class, Appearance, Coating mass per unit area g/m2, corrosion protection