Conversion Coating

Conversion Coating

Conversion coating is a chemical or electro-chemical treatment applied to manufactured parts that superficially converts the material into a thin adhering coating of an insoluble compound. These coatings are commonly applied to protect the part against corrosion, to improve the adherence of other coatings, for lubrication or for decoration

The most common conversion coating processes for metal parts with industrial use include

  • Chromate (aluminum, steel)
  • Phosphate (steel)
  • Bluing (steel)
  • Blackening (steel)
  • Anodizing (aluminum)

US military specifications for conversion coatings include MIL-DTL-5541, MIL-DTL-81706, and MIL-DTL-5574, all dealing with aluminum