Effects of Nano-Ceramic Particle Addition for Cold Sprayed Fluoropolymer Coatings

Abstract

Semi-crystalline polymers such as fluoropolymers are extremely difficult to coat with using solid-state deposition technique such as cold spray (CS) due to its high viscoelastic-viscoplastic behavior. Generally, fluoropolymers solid-state deposition using CS are characterized by a relatively low deposition efficiency (DE) as compared to metallic materials using this deposition technique. In this article, the study on the effect of hydrophobic fumed nanosilica (FNS) and fumed nanoalumina (FNA) in Perfluoroalkoxy (PFA) solid-state deposition using CS has been studied. This study incorporated certain parameters related to the CS process. In addition, powder modification technique using hydrophobic FNS and FNA as additive to feedstock has been studied as well. The results show a number of parameters affected the DE; particle size, traverse speed, gas temperature, and addition of hydrophobic fumed nanoparticles, indicated a better DE. Moreover, PFA coating produced in this manner, retained its hydrophobicity.