An alternative, Steelshield from CFM Companies, Bridgeview, Ill. (www.cfmgroup.com), combines electrogalvanized coil steel with layers of zinc, metal treatments, sealers, primers, and finish coats of paint. The zinc coating, treatments, and topcoats provide greater corrosion resistance than G40 HDG steel with similar topcoats. Tests also show that Steelshield forms and stamps well with less tool and die wear. It also welds the same as painted steel. Depending on the type of Steelshield, warranties range from 3 to 15 years.
A step above steel
Manufacturers often have a hard time getting supplies of high-quality HDG (hot-dipped galvanized) coil-stock steel that has a good formability, surface finish, and corrosion resistance.