Method for depositing an anti-corrosion coating

A process for depositing a corrosion-protection coating on a metallic substrate, the metallic substrate having at least one cavity having an equivalent diameter emm<2 mm and a length/width ratio of greater than 150, comprising the step of:

• depositing, on at least one portion of at least one of said at least one cavity, an aqueous suspension to form a substrate-suspension assembly, said aqueous suspension comprising powder of a metal to be deposited on said substrate, a protective agent for protecting surfaces of the metal powder, a diluent, an aqueous solvent, and at least one additive promoting wetting of said aqueous suspension on said substrate, wherein the particles of the suspension each have an equivalent diameter d such that d≦emm/10 and the additive is at least one organic compound selected from the group consisting of binder, dispersant, complexing agent, wetting agent, and plasticizer.