Zinc-manganese alloy electrodeposition

Zinc alloy electrodeposits are finding increased acceptance as improved replacements for conventional electrogalvanized finishes. Zinc-nickel appears to be experiencing the most widespread use, although zinc-iron also have well-defined market shares. The experimental investigations reported here examine the conventional sulfate-citrate bath, concentrating on its stability, and investigate the effect of high-speed electrodeposition using a rotating cylinder electrode (RCE) and cell to simulate electrolyte flow. The corrosion resistance of steel panels coated with electrodeposited zinc-manganese alloys of different compositions was examined in the ″as-plated,″ ″phosphated″ and ″phosphated and cathodically electrocoated″ states in a conventional 1000-hr continuous neutral salt spray test (ASTM 117 B).