Possibility of spraying of copper coatings on polyamide 6 with low pressure cold spray method

This paper discusses metallization of polymers using a low-pressure cold spray (Dymet 413). Three commercial copper powders: i) spherical and ii) dendritic were deposited on thermoplastic polymer - polyamide 6 (PA6). It was difficult to successfully apply a copper coating directly on the polymer substrate, therefore interlayers were applied. Additionally, the copper powder was pre-treated in hydrogen atmosphere to remove the oxide layer and reduce its critical velocity. Finally, the adhesion strength, electrical conductivity, oxygen content and microstructure of resulting coatings were determined. Coatings were characterized by one order of magnitude of lower conductivity than the bulk material and bond strength of 3.6 MPa. The powder shape turned out to have a decisive effect on the possibility on coatings formation.