Surface coati̇ng application and characterization of polymer structures produced by additive manufacturi̇ng

The metallization process, which involves the coating of the surfaces of 3D (three-dimensional) printed polymer structures with a metallic thin film, represents a convergence of the advantages inherent to additive manufacturing technology, metals and polymers. Consequently, the final product is a potential material for a range of structural applications. The metallization process enhances the characteristics of polymer structures that are unfavourable, including low electrical conductivity, poor mechanical properties, degradation under various environmental conditions, such as ultraviolet (UV) radiation and moisture, and poor thermal properties. Therefore, more functional polymer structures are produced. Recently, researchers have focused their efforts on the metallization of 3D-printed polymer structures with the objective of enhancing their functionality. In this thesis, 3D polymer structures were fabricated using polylactic acid (PLA) filament and fused deposition modelling (FDM) technology. Prior to metallization, five distinct surface treatments were employed to ensure optimal surface conditions. These included as-printed, dipping, vapour, plasma, and abrasion. Subsequently, the polymer structures were metallised through the deposition of aluminium and copper metallic thin films. The morphological, structural, optical, and electrical properties of these structures were examined through the utilisation of a scanning electron microscope (SEM), energy dispersive spectrum (EDS) analysis, atomic force microscopy (AFM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) analysis, ultraviolet-visible light and near infrared (UV-VIS-NIR) analysis, contact angle measurement, ellipsometry analysis, and electrical resistance measurement. The results of the EDS and XRD analyses confirm the presence of aluminium and copper in the polymer structure. The contact angles for aluminium and copper coatings vary up to 91.728° and 88.309°, respectively. The electrical conductivity values of 6.6x105 S/m for aluminium and 7.87x105 S/m for copper at 1000 nm were obtained.