Compressive Properties of 3D Printed Polylactic Acid Matrix Composites Reinforced by Short Fibers and SiC Nanowires

Fused deposition modeling (FDM) as a rapidly growing additive manufacturing technology is successfully applied to several industries. In this study, effects of printing layer thickness, reinforcement types, and silicon carbide nanowire (SiC_nw) brushing layers on compressive properties are investigated by comparing the strength and modulus of the FDM specimens acquired from compression tests. First of all, the printing layer thickness determines the strength of the printed specimens, the pure polylactic acid (PLA), the PLA reinforced by short carbon fiber (C_f/PLA), and the PLA reinforced by graphene (G/PLA). The results indicate that both strength and elastic modulus of the printed specimens increase with the decrease of the printing layer thickness. Therefore, the effects of different reinforcement types on the mechanical properties are further investigated at the same printing layer thickness. It indicates that the printed C_f/PLA receives the highest elastic modulus up to 1.69 GPa due to the high modulus of carbon fiber. Finally, the SiC_nw brushing layers between the printed PLA layers are found to significantly increase the compressive modulus and there is a growth of 55.1% from pure PLA to PLA with three SiC_nw brushing layers.