Characterization and analysis of printing challenges with high filled alumina filament in low-cost extrusion-based additive manufacturing

Fused Filament Fabrication (FFF) offers promising solutions for producing fully ceramic parts using highly filled composite filaments made of polymeric binders and ceramic particles. However, the literature presents critical gaps: what materials constitute the binder, and how can the material's brittleness during the 3D printing process be managed? Addressing these questions is essential for understanding the printability of these materials and expanding their use across a wider range of 3D printers. Nanoe/Zetamix (TM) alumina-filled filaments, with potential applications in Tissue Engineering, particularly in 3D-printed scaffolds, highlight these challenges. This study focuses on three aspects: (i) material characterization; (ii) 3D printing method development; and (iii) evaluation of printed parts. Material characterization identified the filament as polyolefin-based, likely blended with polyester, with transition temperatures indicating efficient processing and strong layer bonding. A dual-filament method was developed to overcome brittleness, enabling the printing of small parts without damaging the filament or disrupting extrusion. Printed parts demonstrated stability, but mechanical properties varied after sintering. While the filament extruded well, brittleness impacted printability, and low viscosity affected layer stacking. This study underscores the potential of filament for scaffold fabrication but highlights the need for further research to optimize porous structure printing.Highlights Fragility of highly filled alumina composite filament limits its overall printability 3D printing with this material needs advanced knowledge and a special method Buildability depends on precise extrusion temperature and layer stacking strategy Aligned layer stacking improves material's self-support and layer bonding capacity Material's properties are promising for 3D printing ceramic structures for bone recovery