A black oxide finish offers a combination of properties that cannot be provided any other way. This conversion coating does not change the dimensional, physical or mechanical properties of the surface treated. The finish is inexpensive and easy to apply.
It has an excellent appearance and is abrasion resistant. A uniform black coating for ferrous metals. Mostly a decorative coating. Only very limited corrosion protection under mild corrosion conditions. It is a conversion coating formed by a chemical reaction with iron in the metal to form an integral protective surface.