On optimizing CO2 laser cutting of 3D-printed PA12/CNTs composite sheet Kerf characteristics

Abstract Fused filament fabrication (FFF) 3D printing enables the cost-effective production of functional polymer parts, including advanced composites like carbon nanotube (CNT)–reinforced polyamide 12 (PA12) reported in this study. Polymer composites manufactured by FFF exhibit a lightweight character, due to plausible complex structures that can be realized with minimal waste of material. However, surface defects, weak bonding between the adjacent beads and the printed layers, as well as anisotropy, persist in the final parts. Therefore, improving print parameters and post-processing is crucial for enhancing 3D-printed specimens’ quality and expanding applications in various high-performance, demanding, and niche applications, as for instance in biomedical, aerospace, automotive, and electronics sectors, among others. This study presents new experimental findings on polyamide 12/carbon nanotube (PA12/CNT) nanocomposites manufactured using FFF 3D printing and finished in their final shape with a laser beam. Six parameters were selected and then tested following a fifty-four-run central composite design (CCD) experimental approach. The Kerf characteristics, including upper and bottom width and the roughness of the cut surfaces, were measured and optimized according to the signal-to-noise ratio (SN) and desirability methodology. This approach enhances Kerf surface attributes, achieving Ra values of less than 6 µm and Kerf widths of approximately 0.25 mm (upper) and 0.15 mm (bottom) for optimal parameter settings, making the specimens suitable for innovative applications that require advanced nanocomposites.