Description
It is increasingly difficulty to deal with the contamination of waste water from zinc phosphate or zinc-calcium phosphate coatings. This paper describes a conversion coating process involving the electrolytic deposition of a calcium phosphate carrier coat. The process is efficient, free from heavy metals and sludge, and well suited for wiredrawing, cold heading, and extrusion. The paper highlights the cost savings, environmental benefits, and productivity improvements that can be achieved by a combination of calcium phosphating with a polymer coating.
