Tech: Alodine Clear / Iridite Clear

Iridite Clear (Chem Film – DTL-5541 Type II)


Iridite Clear, also known as chromate conversion coating or “chem-film”, is a protective film applied to aluminum and its alloys. Here are the key points:


               Purpose:

                               Provides corrosion protection.

                               Acts as an adhesion promoter for paint or adhesive bonding.

                               Conductive (typically no more than 5 milliohm resistance).

                               Coating thickness: 10-40 millionths of an inch.

               Process:

                               RoHS and WEEE compliant.

                               Application methods: dip, brush, swab, or spray.

                               The coatings range from clear to dark yellow (Clear is ROHS compliant) .

               Regulations:

                               Iridite NCP and Alodine 5200 are hexavalent-chrome-free alternatives.

                               Used in auto industry (brake calipers, electrical components) and aerospace (paint and primer application).


               Specifications:

                               MIL-DTL-5541 (formerly MIL-C-5541)

                               ASTM B449 (Hexavalent Chromate)

                               ASTM B921 (Non-Hexavalent)

                               AMS 2473 (General Purpose Applications)

                               AMS 2474 (Low Electrical Resistance Applications).