Method of Forming Corrosion Resistant Coating and Related Apparatus

Abstract

A method of forming a corrosion-resistant ceramic coating on a metallic substrate, the method comprising providing a passivation layer on a surface of the metallic substrate by electrochemical passivation of the metallic substrate under a first electrical current and using a first electrically conducting solution; and providing the corrosion-resistant ceramic coating on an outermost surface of the metallic substrate, the outermost surface in use adapted to be exposed to a corrosive environment, by plasma electrolytic oxidation of the metallic substrate with the passivation layer, in a second electrically conducting solution and under a second electrical current having a discharge voltage. The first and the second electrically conducting solutions comprise a tetrafluoroborate compound.

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