High Performance Alternative to Zinc PlatingJune 1, 2011
NOF Metal Coatings North America Inc., Chardon, OH, and Curtis Metal Finishing Co. (Sterling Heights, MI, and Machesney Park, IL) have launched ZnCoat, a new finish designed as an alternative to zinc plating for fasteners and small parts. ZnCoat, a zinc-rich coating for ferrous metal alloys, is entirely chromium-free and provides superior corrosion resistance with a thin film, without risk of hydrogen embrittlement. Compared to conventional zinc plating, which is passivated using hexavalent or trivalent chromates that provide a thin-film passivation layer only on the surface of the zinc plating, ZnCoat features environmentally friendly passivation agents and corrosion inhibitors throughout the film. This makes the coating (reportedly) far less susceptible to early failure.
The coating is further enhanced by a self-repairing mechanism—if a coated fastener is abraded during installation, zinc oxides and carbonates form at a controlled rate at the damaged area, sealing the breach in the coating and restoring barrier protection. ZnCoat is applied (under license by Curtis Metal Finishing) to steel parts through a nonelectrolytic dip-spin coating process (which does not produce hydrogen as a byproduct).
Curtis Metal Finishing: 586/939-2850; www.zncoat.comNOF Metal Coatings North America, Inc.: 440/285-2231; www.metal-coatings.com
View Glossary of Metalforming Terms