Modeling the effect of 3D-printed induced defects on mechanical performance of natural carbon-enhanced polymer composite

3D-printing induced defects are intrinsic to the layer-by-layer deposition process, which results in reduced performance of materials fabricated using extrusion-based additive manufacturing (AM) techniques. In this study, the effect of porosity introduced by fused deposition modeling (FDM) AM technique on the mechanical performance of natural carbon-enhanced polymer composite (NCPC) materials was evaluated experimentally and through finite element analysis (FEA). Computed Tomography (CT) scans of 3D-printed and traditionally fabricated specimens were used to evaluate porosity and generate the mesh for the FEA model. The FEA results showed that a porosity level of 5.6% led to a reduction in ultimate tensile strength (UTS) and flexural strength (FS) by approximately 6%, compared to a non-porous FEA model. However, the experimental 3D-printed samples showed a 7% lower UTS and 39% lower FS compared to the FEA porous model. As expected, the injection-molded NCPC materials outperformed the compression-molded and 3D-printed samples for both experimental and FEA results.