Black oxide is used to provide a protective, corrosion resistant coating over metal. It has a uniform black finish that does not alter the dimensions of the part after processing. The finish does not chip or peel and acts as an absorbent to hold oils. Black oxide is a chemical conversion coating that is not deposited on the surface of the metal. Instead, the black oxide coating is produced by a chemical reaction between the iron on the surface of the metal and the oxidizing salts present in the solution. The result of this chemical reaction is the formation of black oxide on the surface of the metal being coated.

This coating is economical and offers a variety of valuable properties to extend the service life and improve performance of the parts that are coated.

Some of the industries that utilize black oxide coating are: automotive, firearms, mower blades and a host of others that want an economical coating for their metal parts.

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