Chromate Conversion
Chromate conversion coatings are produced on Aluminium by chemical methods. The coatings are usually applied by immersion, spray or swabbing.
The appearance of the film can vary from a silver colour to dark yellow depending on the solution composition. Chromate films are thin and not very abrasion resistant but do give exceptional corrosion resistance with low electrical resistance.
Paint and organic finishes adhere well to the chromate film and it is often used as a base coat.
The most common type of conversion coating in use today is known as Alocrom. This available in 2 major variations, Alocrom 1000 (clear film), and Alocrom 1200 (golden film).