Traditionally, conversion coating pretreatment process options have been limited. For the most part, they include either an iron or zinc phosphate. Although these have been sufficient in performance in the past, concerns have recently risen regarding their inefficient energy and water usage.
Iron Phosphate Pretreatment Systems
Iron phosphate systems are most often used when a durable finish is required but the parts are not exposed to extremely corrosive environments. These systems involve up to six stages, including multiple cleaning and rinsing phases which require a lot of water and energy.
Zinc Phosphate Pretreatment Systems
Zinc phosphate coatings provide exceptional durability even in corrosive environments and they are capable of coating mixed metals. However, zinc phosphate systems require even more phases than iron systems. Zinc phosphate systems are different in a couple ways from an iron system. Primarily, the zinc system requires a surface conditioner stage, which happens just before the zinc phosphate stage. Since the surface conditioning chemistry is a colloidal suspension, it ages over time and must be dumped frequently to be effective. Again, wasteful in energy and water.
New Conversion Coatings Options
Although many improvements have been made to both the iron and zinc phosphates systems, a new technology has emerged that offers significant benefits. These new processes are shorter and operate at lower temperatures. They perform well in meeting finishing specifications on all standard metal materials and are significantly better for the environment. And, they offer meaningful cost savings to manufacturers.
The new coating is zirconium based, containing no zinc, manganese, nickel, or phosphates. When applied to the metal surface, the chemicals react to form a coating that is considerably thinner than the traditional iron and zinc coatings. The coating is applied using fewer stages resulting in up to a 30% reduction in a plant footprint and much less water usage.
Production Systems is at the forefront of pretreatment and finishing technologies. We can assist your company is the design and integration of finishing systems ranging from pretreatment and surface prep equipment to spray paint and powder coating booths. Contact us today to learn more about our engineering and manufacturing capabilities.
