Black Oxide Plating Key Terms

Be conversant with the terminology for the black oxide plating process

By Howard Robertson

Black oxide plating (or black oxide coating or blackening) can increase the useful life of your industrial tools and machinery, as it improves corrosion resistance of the base surface. The black oxide plating process also provides better dimensional stability and appearance to the component surface than other plating processes. Understanding black oxide plating key terms will help you make smarter choices. This guide covers some of the common terms that you will hear about from plating service providers, including surface preparation, conversion coatings and Mohs scale.

Surface preparation

For efficient adhesion of coating to the component material, you will need to clean the component surface before applying any coating. There are several techniques of surface preparation, such as sand blasting, shot blasting and abrasive blasting.
Try: Mec Shot, a manufacturer of blasting machines, discusses different surface-preparation techniques.

Conversion coating

Conversion coating is an inorganic pre-treatment for a metal component that improves adhesion and corrosion resistance of the metal surface.
Try: Anoplate Corporation, a metal-finishing service provider, offers information about conversion-coating methods.

Black oxide plating

Black oxide plating is a conversion coating that is formed by a chemical reaction with iron in the metal to form an integral protective surface. You can apply black oxide coating to various metals and alloys, including steel, copper and brass.
Try: You can refer to the basics of the black plating process at SWD, a black oxide plating service provider.

Hot black oxide plating

Generally, plating service providers perform the black oxide process at high temperature and hence, the process is known as hot black oxide plating.
Try: To learn more about the hot black oxide plating process, visit Finishing, a resource for the finishing industry.

Cold black oxide plating

As the name indicates, cold black oxide plating (or room temperature black oxide plating) does not require heating of the metal components. This process is applicable for batch production and touch-up work for larger parts. However, this process does not always meet standard specifications.
Try: You can learn about the cold black oxide plating process at Cleveland Black Oxide, a metal-finishing company.

Mohs scale

Mostly, metal-finishing service providers specify the surface hardness of black oxide coating by using the Mohs scale. You will need to specify the surface hardness for your components as per the application requirements.
Try: You can read through the basics of the Mohs scale at wiseGEEK, an information resource.

MIL spec plating

Metal-finishing service providers specify their metal-plating capabilities in terms of different specifications. The U.S. Army Research Laboratory develops and publishes specifications known as MIL spec (or military specifications).
Try: Aerospace Defense Coatings of Georgia, a metal coating service provider for the aviation industry, explains the MIL specs of the black oxide plating process and its scope.