Zinc Plating


Zinc plating is a proven process used to combat the corrosion of steel. In the zinc plating process a bond is created between the zinc and steel forming an iron rich alloy. When corrosion appears, the zinc corrodes before the steel, allowing the steel to go unmarred. The zinc plating process can be considered an excellent primer for paint surfaces, with the paint protecting the zinc, giving a lasting protection. Rust, which gets under paint films and lifts them from the steel, will be inhibited from forming because of zinc plating. Should the part require longer corrosion protection, depending on end use, zinc chromate conversion coatings are used.


Trivalent (Hex-free) Chromate plating provides additional corrosion protection over the zinc, and a topcoat or sealer can also be added for even more corrosion resistance.


Zinc Plating Defined


Zinc coatings prevent oxidation of the protected metal by forming a barrier and by acting as a sacrificial anode if this barrier is damaged. Zinc oxide is a fine white dust that (in contrast to iron oxide) does not cause a breakdown of the substrate's surface integrity as it is formed. Indeed the zinc oxide, if undisturbed, can act as a barrier to further oxidation, in a way similar to the protection afforded to aluminum and stainless steels by their oxide layers. The majority of hardware parts are zinc plated, rather than cadmium plated.


Howard Finishing can plate parts such as stampings, brackets, rods, washers, wires, baskets, and plates.