Microstructural Refinement Through Overspray Control

The usage of micron and submicron powder sizes in suspensions has promoted a better understanding of coating microstructural effects resulting from overspray—material which deposits away for the region targeted by the torch. While these deposits can produce beneficial columnar microstructural features, the SPS process typically produces an undesirable amount of overspray, degrading coating properties such as adhesion, erosion resistance, and surface roughness. The problems associated with overspray are often more pronounced with SPS, but the same phenomena affect APS coatings as well. Progressive Surface has invented a method for controlling the deposition and incorporation of overspray during SPS and APS coating production. This method will be presented along with results of its use.