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

摘要

Common issues such as ice accretion formed on wind turbine blades and lightning strikes aeroplane can be mitigated by metallizing polymers and composites that are used on the outer surface. Cold gas dynamic spray is a novel process that has the potential to metallize the surface of polymer and composites 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 non-metallic surfaces using a commercially available low-pressure cold spray process. The behaviour of the individual metallic particles upon impact on the polymers and the deformation of the substrate was characterized by coating the two feedstock powders onto nylon-6 substrate using a wide range of temperature. Coating thickness up to 1 mm was deposited for the Cu-Zn coating onto nylon-6 substrate using optimised parameters. To understand the deposition of the metallic powder onto the polymers, numerical modelling was conducted using computational fluid dynamics. The correlation of the gas and particle modelling with the coating microstructure highlighted the major importance of the particles velocities during cold spray deposition.