Electrodeposition of Tin-Nickel Alloys From Oxalate-Ammonium Electrolytes

The processes of electrodeposition of tin-nickel alloys onto steel grade 08kp from oxalate-ammonium electrolytes and the physicochemical properties of the resulting coatings were studied. It was shown that electrodeposition proceeds with high polarization, in contrast to the deposition of tin-nickel alloys from chloride-fluoride electrolytes. The highest corrosion rate (26 μA/cm) was observed for the sample coated using the chloride-fluoride electrolyte. Low corrosion rates were recorded for samples coated with tin-nickel alloys containing low nickel levels and deposited from oxalate-ammonium electrolytes with the addition of reagent OS-20 (1.2- 5 μA/cm). The influence of the alloy component ratio on the chemical composition and microstructure of the coatings was demonstrated.