Assessment and Comparison of Tensile and Flexural Properties of 3D-Printed Polylactic Acid-Polylactic Acid/Aluminum Multimaterial Components

This study investigates the tensile and flexural properties of polylactic acid (PLA)-polylactic acid/aluminum multimaterial components. The aim is to characterize 3D-printed components of composite filaments produced using laboratory (desktop) extruders. The composite filament comprises a PLA polymer matrix and 40 wt.% aluminum particles as the reinforcement. The multimaterial (PLA-PLA/aluminum) tensile and flexural specimens were printed using a single nozzle fused deposition modeling 3D printer. These samples are composed of ten layers; the lower eight layers are made of PLA, and the upper two are composed of PLA/aluminum. An optimization process obtains this structure. In addition, scanning electron microscopy (SEM) was used to study the fracture section of the samples; the distribution of reinforcing particles and the fracture behavior of the samples were analyzed. Furthermore, the mechanical and structural characteristics of the samples manufactured using laboratory filament were compared to those of a commercial PLA/aluminum filament. The results showed that adding aluminum powder increases the formability of the composite filament compared to the pure PLA filament. On the other hand, pores (intra- and inter-layer) increase, and the mechanical strength diminishes.