Passivation is a term for a variety of processes that make a metal or other substance unreactive, or passive, by altering the surface layer or coating the surface with a thin inert layer. Because ferrous metals flake when oxidized (e.g. rusts), anodizing is not an appropriate protection technique.
As a result, passivation is most commonly used for ferrous parts, especially stainless steel. For ferrous metals passivation removes free iron molecules embedded in the surface of the part and leaves a protective coating which protects the underlying material.
In addition to our Passivation services, AOTCO plates and anodizes many exotic and uncommon Substrates that most plating providers won’t or can’t do. See a list of the Substrates we commonly plate here.