PPG Industries’ industrial coatings business has introduced the VERSABOND pretreatment system, a fast kinetic-efficient zinc-phosphate pretreatment formulation that improves the corrosion resistance of mixed-metal substrates while enabling manufacturers to realize the environmental and energy-saving benefits of extended bath life, reduced sludge and lower processing temperatures.
Based on proprietary hypernucleation technology developed by PPG, the Versabond system incorporates a rinse conditioner that causes small, densely packed zinc-phosphate crystals to deposit on mixed-metal substrates, accelerating bond formation with the coating, particularly on surfaces with higher concentrations of aluminum.
Randy Brent, PPG director, pretreatment and engineered products, said development of the Versabond system is significant for end-users and parts manufacturers because it supports “light-weighting” of trucks and passenger vehicles while reducing waste and energy use during production.
“Demand for lightweight auto and truck components for improved fuel economy is a primary industry trend,” Brent explained. “Standard zinc-phosphate pretreatment products typically require extensive maintenance, analysis and tight control when applied to parts with more than 10 to 15 percent aluminum content. The Versabond pretreatment system is a major advance because it enables manufacturers to coat mixed-metal parts with up to 40 percent aluminum without modifying their process systems.”
The proprietary zinc-phosphate formulation in the Versabond pretreatment system precipitates onto metal surfaces about twice as fast as traditional zinc-phosphate products and produces a tight, lattice-like network of microcrystals. The result is greater metal adhesion and fewer voids in the coating system, which leads to more effective corrosion protection.
Depending on the composition of the metal mix, the Versabond pretreatment system may process at temperatures up to 20 percent lower than those required for conventional zinc-phosphate formulations. It also extends average bath life from two weeks to eight weeks and generates 30 to 50 percent less sludge, resulting in less waste, lower energy consumption and fewer maintenance demands.
The Versabond pretreatment system is engineered to improve the corrosion resistance of underbody truck and vehicle parts such as springs, control arms, tie rods, frames and exhaust system components. It also can be used on appliances and heavy-duty equipment (HDE) components, and by general manufacturers seeking to upgrade a zinc-phosphate pretreatment system.
