ELECTRODEPOSITION OF ZINC-COBALT ALLOY FROM CYANIDE-FREE ALKALINE PLATING BATH

Zinc-cobalt alloy coating having 0.3 to 1.0 percent cobalt has been de posited from a conventional non-cyanide alkaline zinc plating bath con taining zinc, NaOH, and proprietary addition agents, The alloying elem ent, cobalt, is added to the bath together with a complexing agent, Th e influence of plating bath and process variables, such as temperature , agitation and current density on alloy deposition was studied in det ail, The deposit characteristics and corrosion resistance of the Zn-Co coating were evaluated and compared with conventional alkaline zinc, The Zn-Co alloy accepts all usual chromate conversion coatings with a modification in composition, pH and time of immersion.