ELECTRODEPOSITION OF ZINC-IRON ALLOY.

The corrosion resistance of zinc can be improved by alloying zinc with iron. The Jasco Stronzinc Process is a method to electroplate a zinc-iron alloy on metal substrates in an alkaline zincate bath containing a small amount of chelating agents. The new zinc-iron alloy layer has five times the corrosion resistance of ordinary zinc of the same thickness. The Jasco Stronzinc alloy is 99. 3-99. 8% Zn and 0. 7-0. 2% Fe. Principal ingredients of the zinc-iron alloy bath are sodium hydroxide, zinc ions, chelating agents, iron ions and proprietary brighteners. Iridescent or black chromated zinc-iron alloy coatings resist corrosion for 2,000 hours or more in the salt spray exposure test standardized in Japan. Waste disposal requirements for this process are minimal. It is only a neutralization process. Electroplated zinc-iron alloy layers are strippable by hydrochloric acid. Process details are presented.