Black oxide is a conversion finish that provides essential protection – and a distinct black coloring – to ferrous metals by creating a chemical reaction within them. The chemical reaction allows a protective coating to be formed without increasing part dimensions, dulling the part’s luster, or altering the hardness of the metal. Because black oxide does not actually apply a coating that bonds to metal, it cannot chip or rub off. Metal that undergoes black oxide conversion also receives two more distinct advantages: dimensional stability and corrosion resistance. After black oxide, parts receive a supplemental post treatment of a rust preventative.
Heavy, light, and a dry-to-touch options of organic and inorganic rust preventatives or inhibitors are available. Also available to this process is an extra step of SPIN DRY to remove excess rust preventative from parts with threads.