Characteristics of Non—Cyanide Acid Zinc Plating Baths and Coatings

SUMMARY

Zinc coatings may be electrodeposited from cyanide, alkaline or acid baths. However, cyanide electrolytes are highly toxic and substantial investment is required for effluent treatment. Hence, they are being replaced by chloride and non-cyanide alkaline electrolytes.

Results from a study on the conductivity, cathode polarisation, throwing power, cathode current efficiency, and anode efficiency of a bromide bath are given. The nature of deposit, its microhardness, porosity and structure, characterised using the scanning electron microscope, are reported.

Keywords:

• non-cyanide electrolytes
• zinc plating baths
• bromide baths