Black Oxide

Black oxide stands alone among finishes, both for its unique set of properties and cost-effectiveness – making it ideal for certain applications. Known as a conversion coating, black oxide is produced when parts are introduced into an alkaline aqueous salt solution (with a temperature around 285 degrees F). A magnate (Fe3 O4) is produced on the surface of the part following a reaction between the hot oxide bath and iron of the ferrous alloy (although non-ferrous metals can similarly form black oxides under suitable conditions). While applying black oxide at room temperature is possible, the “hot” oxide process is known to produce the greatest array of benefits. Cold black oxide results in variations in color from one part to another, with black material frequently rubbing off simply by touching the surface. Of note, military or automotive specifications do not call for the cold black oxide process.

Black Oxide Advantages