For all kinds of machine components and technical items electrogalvanizing with varied chromating is still the most frequently-employed protection against corrosion. This process is particularly indispensable where lacquer and powder coating would clog small holes or threading.
Almost 100 % of the parts to be galvanized are made of iron and steel. Because of its physical chemical properties, zinc is referred to as a "sacrificial metal", i.e. it protects the steel underneath until it is itself eroded by corrosion.
Chromating after electrogalvanizing considerably helps improve protection against corrosion by delaying the onset of zinc corrosion (white rust).
It is generally true that yellow-iridescent and black chromate layers on zinc offer a greater degree of protection than transparent or blue.
With the "pickled zinc process" we use, zinc plating with blue, yellow or black chromating can be produced on steel and castings, covering perfectly and, depending on the surface, with a high gloss.