Nadcap Chemfilm Alodine Example

ChemFilm (Nadcap Accredited)

Chemfilm, sometimes called aluminum chromate, Alodine or Iridite, is a chemical conversion coating that is used to passivate aluminum. It protects aluminum substrates from corrosion and serves as a base for organic coatings while leaving dimensions unchanged. Chemfilm is applied by dipping, spraying or brushing. It is sometimes applied alongside Type II Anodizing  and can be used to repair minor damage to anodized surfaces (up to 5% of surface area per MIL-A-8625). The resultant coating is dependent on the substrate condition and not intended for decorative use.

Chem film per MIL-DTL-5541 Class 3 is electrically conductive. The best corrosion protection is provided by chem film perMIL-DTL-5541 Class 1A.

Chem Processing offers both trivalent (RoHS compliant) and hexavalent chromium based chem film. 


Chem Processing Inc. CHEMFILM Capabilities:

  • Available Masking for Selective Surface Coating
  • Salt Spray Corrosion Test per ASTM B117(minimum 168 hours of salt spray resistance)
  • RoHS compliant Chem Film (MIL-DTL-5541 Type 2)
  • Repair of anodized surfaces (per MIL-A-8625)
  • Post chemfilm Military CARC primer and paint (see CARC page)

Applicable Specifications:

  • MIL-DTL-5541
  • AMS-2473 & 2474
  • MIL-C-81706
  • AMS-C-5541
  • PN 14.12 (UTC Aerospace Systems/Hamilton Sundstrand)
  • PS 114 (UTC Aerospace Systems/Hamilton Sundstrand)
  • HS 240 (UTC Aerospace Systems/Hamilton Sundstrand)
  • WS 9030 (UTC Aerospace Systems/Hamilton Sundstrand)
  • 580-0036 (Rockwell Collins)
  • SP-870 (Woodward)

Typical Chemfilm Applications:

  • Aerospace/Aviation: brush-on chemfilm is used in the repair of anodized surfaces and used general corrosion protection on all manner of aluminum aircraft components
  • Defense/Military: chemfilm is used as a base coat for CARC paint on ordnance, vehicles and tactical equipment
  • Maritime/Naval: chemfilm provides corrosion protection in saltwater environments
  • Electrical Industry: chemfilm is used for corrosion protection on housings

OEM Approvals:

Rockwell Approved Chemical Conversion Coating Raytheon Approved Chemical Conversion CoatingWoodward Approved Chemical Conversion CoatingSpaceX Approved Chemical Conversion CoatingUTAS Approved Chemical Conversion CoatingL3 Communications Approved Chemical Conversion CoatingMoog Approved Chemical Conversion Coating


Chem Processing Inc. offers chemfilm/alodine/iridite services to Illinois, Wisconsin, Iowa, the Midwest and beyond. CPI is strategically located by highway routes to Chicago, Milwaukee, Madison, St. Louis, and Minneapolis. The CPI facility is minutes from Rockford Chicago International Airport, a major Midwestern air freight hub, enabling efficient door-to-door delivery across the United States or across the globe.