Development of in-house PC/ABS blends and optimization of printing parameters for material extrusion method

In the field of Additive Manufacturing (AM) with Material Extrusion (MEX) technology, polycarbonate (PC) and acrylonitrile butadiene styrene (ABS) are two widely used thermoplastics, each offering distinct advantages. Standalone PC possesses high strength and thermal resistance but suffers from poor printability, whereas ABS offers good processability but lower mechanical performance. Herein, aiming at balancing their advantages, in-house blends with varying PC/ABS ratios were developed. Specifically, optimal set of parameters (heat zones temperatures, screw speed, fan speed) has been determined to produce filaments from each blend at different ratios. Additionally, a statistical Design of Experiments (DoE) approach based on the Taguchi method was employed to identify optimal set of printing parameters (layer thickness, nozzle temperature, print speed) and their significance on ultimate tensile strength. From this analysis, layer thickness was found to have a considerable influence on the ultimate tensile strength across most material combinations, while nozzle temperature only in some blends. Printing speed showed no statistically significant effect. Furthermore, samples printed using the optimal parameter combinations were evaluated through tensile testing, three-point bending, hardness, and impact testing. Fractographic analysis was also conducted to better understand the fracture mechanisms of the different material blends.