The Challenges of Thermosetting Polymers Metallisation via Low-Pressure Cold Spray

Metallisation is the process of applying a metallic coating on the surface of a non-metallic component for structural, functional, or decorative purposes. It can be used to replace metallic parts with metallic-coated polymers with the objective of weight and cost reduction, or to extend the field of application of polymeric components granting them thermal or electrical conductivity. For example, it is used in aerospace applications to provide conductivity as protection against lighting strikes. Cold Spray was demonstrated to be suitable for the deposition of metallic coatings on polymer-based substrates without any prior surface treatment. It can be considered as an environmentally friendly alternative for the traditional electroplating metallisation practices and thermal spray coatings technologies as it is a non-combustion process and any unadhered powder residues can be easily disposed of while the metallisation via Cold Spray of thermoplastic polymers was reported by various authors in the last few years, the coating of thermosetting presents additional challenges that have yet to be fully resolved. In this work, a low-pressure Cold Spray system with a maximum pressure of 6 bar was employed to investigate the challenges associated with the metallisation of an epoxy resin.