Patent ID: 6899925

Claim:
A method of protecting articles that would otherwise, without said protection, have a clean and exposed bare ferrous metal surface that would be subject to oxidative deterioration upon exposure to ambient environment comprising: applying a zinc coating to a clean and exposed bare surface comprising the ferrous metal surface by dipping the article in a hot liquid bath comprising zinc, then subjecting the article to centrifugal force while the material on the article from the dip is still a hot liquid, thereby removing excess amounts of the zinc coating sufficient to produce a zinc rich coating having a surface that is partially smooth and partially rough; disposing a powder, comprising a meltable precursor of a non-epoxy, electrically insulating, organic thermosetting polymer, on said zinc coating; applying opposite polarity d.c. charges to the powder and the surface, respectively and heating the powder while the charges are applied under conditions sufficient to cause the powder to melt and flow across the zinc rich surface, to convert said powder into a thermosetting polymer, and to adhere said thermosetting polymer to said zinc rich surface; depositing a third coating composition comprising an epoxy modified polysiloxane on said thermosetting polymer in an amount and thickness such that said thermosetting polymer is substantially covered.