Sustainable Reinforcement of PLA Composites with Waste Beech Sawdust for Enhanced 3D-Printing Performance

Abstract

This study investigates the incorporation of waste beech sawdust (WBS) into polylactic acid (PLA) composites for use in additive manufacturing, with a focus on enhancing the mechanical performance and sustainability of 3D-printed components. WBS, a byproduct of industrial timber processing, was used in varying concentrations (0-20%) to produce PLA composite filaments through a single-screw extrusion process, which were subsequently used in fused filament fabrication (FFF). Mechanical properties including tensile, flexural, and impact strengths were evaluated alongside thermal stability and microstructural analysis. The results indicated that the addition of WBS led to increased stiffness and hardness of the PLA composites, with optimal mechanical performance observed at 5-10% WBS content. Beyond this concentration, significant reductions in tensile, flexural, and impact strengths were noted, likely due to poor particle dispersion and inadequate interfacial adhesion, as confirmed by scanning electron microscopy (SEM) analysis. Thermal stability analysis via thermogravimetric analysis (TGA) revealed a reduction in degradation temperature with increased WBS content, which may limit the use of these composites in high-temperature applications. Despite certain limitations, this research underscores the potential of WBS as a sustainable reinforcing agent in 3D-printed PLA composites. The incorporation of WBS contributes to environmental sustainability by utilizing waste materials while also reducing the dependence on non-renewable resources. The findings suggest that PLA-WBS composites, particularly at lower WBS concentrations, offer an effective balance between improved sustainability and mechanical performance, making them suitable for a range of 3D printing applications. Future studies should focus on enhancing filler dispersion and interfacial bonding to further optimize the properties of PLA-WBS composites.