BLACK OXIDE

If you look around at items used in our everyday lives, most often you will come across steel or stainless steel components that have a black appearance. A portion of these black finishes you will find are produced from black oxide process baths.

A black oxide process bath produces non-dimensional, conversion type coating on the surface of the part. For steel alloys, the complex can be either a copper-selenium complex or a magnetite coating depending on the process bath used. For stainless steel alloys, the most common process bath used is an elevated temperature, caustic soda sodium nitrate process bath. This process bath will produce a magnetite complex resulting in a black finish on stainless steel.

Black oxide finishes on steel alloys, while providing an attractive black color, will not provide any corrosion resistance. These finishes must be treated with some type of post treatment so that the part will not corrode in the environment. The post treatment technologies can be petroleum based oils, water soluble or synthetic, and waxes. For a listing of post treatments available, please see our Post Treatment section.

BLACK OXIDE SOLUTIONS