Phosphate Primer: Strong Pretreatment for Powder Coating

Summary for phosphate primer Discussion

Phosphate primer is discussed as a pretreatment for powder coating. Rocky Lane Honeycutt asks whether phosphating is necessary before powder coating and whether it applies only to metal or also to aluminum. Ted Mooney, P.E. replies that phosphate coating is recommended because it helps improve powder adhesion to the substrate. He also notes that phosphate coatings can be deposited on steel as well as aluminum, so the process is not limited to one base metal. The thread is brief and does not present any opposing view; the practical takeaway is that phosphating is a useful adhesion-promoting pretreatment for powder-coated parts, including aluminum, when the process is appropriate for the substrate and application.