In addition to the traditional white colour of chromium, it is also possible to obtain a black finish, glossy or matt, depending on the deposit used as a substrate (usually nickel).
The shades of black – grey of the deposit are obtained thanks to the presence of additives based on iron, which are deposited at the same time as the chromium.
Like all chromium baths, black chromium plating has a very limited penetrating power. If complex-shaped object needs chromium plating, chromium plating may not occur in low current density areas and the deposit may show a clear gradient.
Black trivalent chromium plating is a type of electroplating process which allows to obtain a pleasing black colour, which can replace varnishing.
It is used for chromium plating of motorcycle mufflers and windscreen wipers of cars, as well as in the furniture industry.
The most important technical and functional application of black chromium plating is for the plating of solar panel components, due to the well-known characteristics of solar energy absorption, low radiant power, and thermal stability of these deposits.
Unlike the traditional black nickel – gun-metal grey finishes, black chromium deposits have the advantage to be superficially abrasion resistant and to not oxidize; therefore, final coating as a protective treatment is not required.