The impact on the mechanical properties of multi-material polymers fabricated with a single mixing nozzle and multi-nozzle systems via fused deposition modeling

Multi-material 3D printing and process parameters optimization using multiple extruders are the significant challenges of fused deposition modeling (FDM). This paper focuses on the filament extrusion method and presents a comparison of two modes: multi-material single mixing nozzle and multi-material multiple nozzles, thereby linking technology with the mechanical properties. Tensile testing specimens were printed in two different scenarios to validate the comparison: (1) multi-material multi-layered section printed using a multi in-out single mixing nozzle and (2) multi-material multi-layered section printed using a multiple extrusion nozzle within the same carriage. Both modes followed a rectilinear infill pattern and different material combinations. The material combinations implemented included ABS-HIPS, ABS-PLA, PLA- HIPS, and PLA-HIPS-ABS. A behavioral study was evaluated on the mechanical properties of these materials. The results provide a tool for selection on which type of mode is considered suitable for maximizing efficiency and performance to fabricate a multi-material 3D printed product.