Sensitivity analysis of process parameters on the properties of carbon fiber reinforced polyether-ether-ketone composites in screw extrusion 3D printing

Material extrusion based on screw extrusion has garnered increasing attention due to its extensive material processing capabilities and high compatibility. However, the relationship between the process parameters in screw extrusion and the properties of the parts requires further investigation. The study aims to investigate the sensitivity of the mechanical properties of short carbon fiber-reinforced polyether-ether-ketone (SCF/PEEK) printed parts to the process parameters in screw extrusion 3D printing. The effects of varying process parameters on the mechanical properties of the parts were investigated through a combination of numerical simulation and experimental testing. The results indicate that extrusion temperature, speed, and nozzle diameter significantly influence the melt extrusion pressure during the extrusion process. Regarding part strength, the most influential parameters were printing temperature and annealing temperature, followed by filling angle, nozzle diameter, printing layer height, and printing line width, while printing speed and annealing time had relatively minor effects on strength. Under the optimized process parameters, the maximum tensile and flexural strengths of the specimens reached 148.8 MPa and 222.1 MPa, respectively. The process parameters affect the mechanical properties and surface morphology of the specimen by influencing the inter- or intra-layer bonding, porosity, and crystallinity. This research offers a crucial theoretical foundation and practical guidance for enhancing the performance of screw-extruded 3D-printed parts, facilitating further applications in this field.