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New Recipe for Fighting Rust By Tim Triplett, Editor-in-Chief Chemcoaters hopes to win over the doubters— and change the economics of galvanized steel. Developing a breakthrough product is only half the battle. Convincing customers to change the way they do business is also an uphill fight. “That’s what I do every day,” says Mike Tieri, director of sales and marketing for Chemcoaters in Gary, Ind. Chemcoaters runs a “green” coil coating operation, offering conventional dry-film lubricants, pretreatments and waterborne prepaints with little or no VOCs. But it’s Chemcoaters’ Eco-Green Coatings subsidiary that is marketing a very unconventional product, which it claims can bring increased corrosion resistance to galvanized steel at a much lower cost. Not surprisingly, there are some skeptics in the marketplace. But Tieri makes a strong case for the patent pending chemical coating. Known as InterCoat® ChemGuard, developed by staff chemist and Director of Product Development Bill Krippes, the proprietary chemistry is said to generate a permanent covalent reaction with any zinc or zinc-alloy coated substrate, bonding to the surface. At the heart of Eco-Green’s patent is the chemical’s “Inter-Reactive®” attributes. This “interreactivity” not only gives it the ability to bond with the zinc, but it will naturally spread to cover an exposed area, even around a cut edge, the company claims. It can be used as a stand-alone corrosion-resistant coating or it can be applied as a hybrid pretreatment that enhances corrosion resistance while simultaneously improving the adhesion of pre-paints, post-paints and powder-coats. “It is not a barrier coating. It won’t rub off,” Tieri says. InterCoat® ChemGuard offers several advantages, Tieri explains: It can improve the corrosion resistance of galvanized steel by a factor of 8-10 times. In some cases, by applying InterCoat® ChemGuard, users can achieve the corrosion protection they need with a less expensive grade of galvanized. InterCoat® ChemGuard contains no hexavalent chromium, which is a carcinogen, so it is RoHS compliant. It offers enough lubricity that in many cases coils can be run dry instead of processed with oil, removing the need to post-clean the material. It can also be tinted to eliminate post-painting of some parts, the company claims. The cost advantage is compelling, Tieri says, citing an example in which G235 galvanized is substituted by G40 galvanized with InterCoat® ChemGuard. G40 carries a much thinner coating of zinc and, even with Eco-Green’s new coating, costs much less. With 16-gauge G40, the zinc premium is about $1.90 per hundredweight. The G235, with a much thicker zinc coating, costs $11.10. Applying InterCoat® ChemGuard costs around $4.00 per hundredweight. Therefore, G40 with InterCoat® ChemGuard costs a total of about $5.90 per hundredweight, a savings of more than $5.00 over G235, while yielding improved corrosion protection, the company claims. “Since G40 is commercially available from many more sources, it means service centers, OEMs and processors can use a lighter and less-expensive zinc coating thickness, have a metal product that is considerably easier to form and shape, reduce SKUs, increase inventory turns, improve corrosion resistance and save money immediately,” Tieri says, depending on the size of the coils. Chemcoaters has subjected the product to weather testing in Indiana and in Florida. Its accelerated ASTM B-117 corrosion test results have been independently verified by Anderson Laboratories, Inc., in Greendale, Wis., and other outside experts, Tieri claims. “We put G40 with InterCoat® ChemGuard through a salt spray test against G235 and beat it. We have a product that offers more corrosion protection, greater availability, is easier to use, and is RoHS compliant. It could not be a bigger winner.” The product has proven itself in the field, he adds. In the four years that Chemcoaters has been selling the coating, it has won over customers ranging from makers of auto parts and appliances to building materials. One early application was metal studs used in construction. Chemcoaters has worked closely with ClarkDietrich® Building Systems, West Chester, Ohio, which uses the coating on its ProSTUD® Drywall Framing System. Other customers are putting the coating to the test, the company says. One large bus manufacturer has specified InterCoat® ChemGuard for corrosion protection of the floor of its vehicles. Service centers are specifying it to eliminate transient rust when coils are shipped from the Midwest to Mexico. Major U.S. appliance manufacturers are testing it to improve corrosion issues in dishwashers and laundry applications. And a major U.S. steel mill is currently running trials to see if it can replace hexavalent chromium chem-treatment with the RoHS compliant InterCoat® ChemGuard. InterCoat® ChemGuard can be customized with various additives for different applications. The formula can be tweaked to improve formability, stampability, lubricity or weldability. “That’s the benefit of an engineered product. We can manipulate that recipe to address whatever the customer might need,” Tieri says. At present, Chemcoaters applies InterCoat® ChemGuard on a toll basis, producing “several thousand tons a month” on its single, high-horsepower coating line in Gary. It can handle coils up to 0.125-inch thick and 72 inches wide, weighing 72,000 pounds. But the company would welcome the chance to supply the coating to others. It would just make sense for the mills to sell galvanized coils with InterCoat® ChemGuard already applied, Tieri says. But that probably won’t happen until Chemcoaters can win over the doubters and the product gains wider acceptance in the marketplace. “The mills are not going to change unless customers ask them to,” he adds. “If we can get a mill to apply the coating, it would be a big home run.”