Zinc plating involves the electrodeposition of a thin coating of zinc metal onto a metal substrate, most commonly steel. The zinc coating creates a physical barrier that prevents rust through a unique, sacrificial process whereby zinc will give itself up before allowing rust or oxidation to occur. Zinc is commonly plated from either an acid bath (bright deposit) or an alkaline bath (semi-bright). It is usually post treated with chromate conversion solution (clear, yellow, or black) which helps passivate the zinc metal and adds longevity to the plated coating.
Zinc plating can be used as a final finish or as an intermediate layer of protection as a preparation for a painted finish or a powder coated finish.