3D printing of continuous carbon fiber reinforced polyphenylene sulfide: Exploring printability and importance of fiber volume fraction

Additive manufacturing (AM) of thermoplastic polymer composites is rapidly advancing in the aerospace industry. Here, fused deposition modeling (FDM) of continuous carbon fiber reinforced polyphenylene sulfide (CCF/PPS) was explored and involved experimental filaments with nominal fiber volume fractions (V_f) ranging from 30% to 50%. The printability was evaluated using a design of experiments to quantify the contribution of process parameters to the printed filament quality, which considered microstructure, surface texture and both the thermal and mechanical properties. Results showed that nozzle height, nozzle temperature, printing speed, and flow rate were most influential parameters to the printing process; the relative importance of the printing parameters depended on the V_f. The filament with 50% V_f was successfully printed despite its high fiber volume fraction and achieved an average ultimate tensile strength of 1930 ± 150 MPa, which sets a new benchmark in strength for composites developed by AM. Nevertheless, there are challenges to achieving that strength in printed components.