Conversion Coating & Chem Film

• ASTM B449 [Nadcap Accredited]
• MIL-C-5541 [Nadcap Accredited]
• MIL-DTL-5541 [Nadcap Accredited, ROHS Compliant]
• MIL-DTL-5541 Type II [Nadcap Accredited]
• MIL-DTL-81706 [Nadcap Accredited, ROHS Compliant]
• MIL-C-13924
• MIL-DTL-13924

Hexavalent Chem Film (“Type I”)

• The traditional process used in creating a Conversion Coating
• Contains hexavalent chromium
• Typical color specification (class) for traditional hexavalent chromate ranges from “clear” to “gold”

ROHS Chem Film (“Type II”)

• A more environmentally friendly option
• Does not contain Lead, Cadmium, Hexavalent Chromium, Mercury or PBB/PBDE compounds
• ROHS chem-film is always “clear” in color, but longer exposure to the solution can make the coat more visibly discernible in daylight

Note: If no type is specified, Type I will be used.

Class 1A

• For maximum protection against corrosion on unpainted items, and increased adhesion on painted items
• These coatings will generally be thicker and darker in appearance
• Class 1A is commonly used on tanks, tubing, and component structures where only exterior protection is required

Class 3

• For protection against corrosion where low electrical resistance is required
• These films are generally lighter in appearance, and of a thinner thickness in order to maintain low electrical resistance
• Class 3 is frequently used in electrical components such as circuit boards or connectors.

• Steel Alloys (black oxide is a common treatment)
• Aluminum
• Beryllium
• Magnesium
• Zinc

• Alodine is a trade name for chemical conversion coating of aluminum
• Because the name sounds like anodize, there is sometimes confusion between the two coatings
• While both are coatings created by immersion, the Chem Film treatment is much thinner than Anodizing and is created without use of electrical current
• Unlike anodizing, Chem Films provide a conductive coating and are sometimes used in conjunction with masking in anodized parts