Aluminum conversion coatings, also referred to as Chemical Film, Irridite or Alodine, protect aluminum substrates from corrosion and serve as a base for organic coatings while leaving dimensions unchanged. Keystone Corporation offers both trivalent (RoHS compliant) and hexavalent chromium based chem film. 

Aluminum conversion coatings are used in countless communications and electronics applications. Traditional uses of Keystone aluminum conversion coatings include:

  • Machinery
  • Electronics
  • Communications
  • Aerospace
  • Military



  • MIL-DTL-5541
  • ASTM B449
  • ASTM B921
  • AMS 2473
  • AMS 2474
  • Commercial and customer generated specifications

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


Coating Benefits:

  • Inexpensive
  • When specified, provide nearly zero electrical resistance
  • Good corrosion protection
  • Excellent base for paint
  • Clear to Yellow in appearance

Contact Keystone Corporation for more information about Aluminum Conversion Coatings

For more than 90 years, Keystone Corporation has assisted customers in completing orders ranging from a few specialized pieces to high volume applications. All finishes are available for both Rack and Barrel plating applications. We maintain superior quality control through the entire finishing process, ensuring top quality conversion coating at an affordable cost for any project. Our experienced staff will provide technical assistance as well as Certificates of Compliance to commercial, government, AMS, ASTM, and MIL specifications. Meeting your manufacturing needs is our top priority at Keystone Corporation. Contact us today to receive a personalized quotation based on your specific requirements.

Plated metal parts

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