Exploring surface preparation for cold spraying on polymers

Polymers and polymeric composites have been widely used due to their low density and high specific strength, but the main disadvantage is low conductivity. Metallization by cold spray has been proposed to solve the problem. However, polymers exhibit poor cold sprayability with regard to deposition efficiency and coating adhesion strength. Possible methods to improve these metrics need to be investigated, and, in this work, the effects of mechanical substrate surface treatment on the cold spray deposition characteristics were explored during cold spraying tin on ABS, PEEK, and epoxy polymers. Mechanically roughening surfaces by transferring patterns onto polymer surfaces by hot pressing increased the deposition efficiency (coating thickness) but adversely affected the coating adhesion strength. Quantitative analysis of the effects of surface roughness pa-rameters implies the existence of an optimal roughness value for deposition efficiency.