Process for continuous deposition of a zinc-aluminum coating on a ferrous product, by immersion in a bath of molten metal

摘要

There is disclosed a method of depositing a protective coating on a ferrous substrate comprising the steps of immersing the substrate in an electrolytic solution containing zinc chloride, a fluoride and at least one of NiCl2 and CoCl2, electrodepositing on said substrate a thin pre-coating comprising zinc, said electrolytic bath also functioning as a flux such that the thin electrodeposited coating comprising zinc will have thereon a flux coating as the substrate is removed from the electrolytic bath; removing the pre-coated substrate from the electrolytic bath, thereafter immersing the pre-coated substrate in a molten metal bath containing zinc so as to deposit a zinc-containing protective coating on said substrate, and removing said substrate from said molten bath.