Coating System for High-Corrosion Applications

PPG, Pittsburgh, PA, has introduced the DragonHide ZRE finish system, a duplex coating system engineered with a self-healing zinc-laden primer between the base metal substrate and electrocoat finish that is said to dramatically improve the corrosion resistance of high-end automobile underbody parts and sub-frame finishes.

“When the barrier coat on an underbody assembly treated with this system gets chipped by road debris, the sacrificial zinc-oxide layer corrodes, causing the basecoat to heal and protect itself,” explains John Zbiegien, PPG product manager, industrial coatings. “That enables highly exposed auto parts to last much longer in service than they do today.”

SpectraCron zinc-rich coating, which works with PPG’s PowerCron electrocoats to form the DragonHide ZRE finish system, has been performance-tested by major auto manufacturers for the past three years and achieved exceptional results, according to PPG officials. Potential applications are control arms, tie rods, linkages, engine cradles, fasteners and other components critical to auto safety, durability and performance. The system also can be used for general finishing applications and by heavy-duty and military equipment manufacturers to produce parts that must survive highly corrosive environments.

In addition to providing corrosion resistance, the finish system enables automakers, heavy-duty equipment manufacturers and military contractors and their suppliers to cut costs and vehicle weight by using thinner-gauge steel for parts; enhance corrosion performance on welds, seams and cut edges; and minimize masking requirements for complex parts. It also can be an economical alternative to galvanizing and plating.