Cold Spraying of Metallic Powders Onto Polymeric Substrates: Influence of Gas Preheating Temperature on the Coating Deposition

Abstract

Abstract Common issues such as ice formation on wind turbine blades and lightning strikes on airplanes can be mitigated by metallizing polymers and composites used on the outer surface of the component. Cold gas dynamic spray is a novel process that has the potential to be used for metallization of polymer and composite surfaces to produce electrically and/or thermally conductive components. In this study, mixed Cu-Zn and Al-Zn feedstock powders were deposited onto polypropylene and nylon-6 substrates to investigate the viability of metallizing nonmetallic surfaces using a commercially available low-pressure cold spray process. The behavior of the individual metallic particles upon impact on the polymers and the deformation of the substrate were characterized by coating the two feedstock powders onto a nylon-6 substrate over a wide temperature range. The Cu-Zn coating was deposited in thicknesses up to 1 mm onto the nylon-6 substrate using optimized parameters. To understand the deposition of the metallic powder onto the polymers, the process was modeled using computational fluid dynamics methods. The correlation of the gas and particle modeling with examination of the coating microstructure highlighted the major importance of the particle velocity during cold spray deposition.