Zinc Iron plating is a soft, ductile, decorative, corrosion-resistant finish. Unlike most other commonly plated metals, zinc Iron protects the substrate by sacrificing itself and thus corrodes before the base metal. For corrosion protection, Trivalent chromates are applied over the zinc. Trivalent Chromates are chemical conversion coatings that add protection and color. The substrate metal participates in the coating reaction and becomes a component of the coating. The collaboration has a profound effect on the properties of the coating. Trivalent Chromate films are typically very thin, on the order of .0000001″ and contribute no measurable thickness to the overall coating.
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