Chromating (Topic: 14081)

Chromating is the most used conversion coating process for aluminium profiles which are going to be powder coated. The chromate layer enhances the adhesion between the metal surface and the lacquer coating, and improves the corrosion resistance of the lacquered product. If the chromate layer is very thick, it will give a very good corrosion resistance, but the adhesion will be poorer compared to a thinner layer. Too thin chromate layers give very good adhesion, but the corrosion protection is poorer.

There are two types of chromating processes:

1. Yellow chromating

2. Green chromating