Influence of infill patterns on mechanical properties of 3D printed ceramics Al₂O₃ via fused deposition modelling for biomedical applications.

Porous alumina stands as a good candidate for syntheticbone tissue scaffold material or porous ceramicprosthetic devices due to its good physical andmechanical properties compared to other engineeringceramics. This is because of load bearing capabilities ofalumina while preserving its significant porosity levelwhich is a crucial factor for various biomedicalapplications. However, manufacturing near net shapes ofceramics with tailored porosity through conventionalprocessing is challenging. Thus, additive manufacturingroutes like fused deposition modelling (FDM) couldsupport in manufacturing such complex designs andshapes. In this research, Al2OPorous alumina stands as a good candidate for synthetic bone tissue scaffold material or porous ceramic prosthetic devices due to its good physical andmechanical properties compared to other engineeringceramics. This is because of load bearing capabilities ofalumina while preserving its significant porosity levelwhich is a crucial factor for various biomedicalapplications. However, manufacturing near net shapes ofceramics with tailored porosity through conventionalprocessing is challenging. Thus, additive manufacturingroutes like fused deposition modelling (FDM) couldsupport in manufacturing such complex designs andshapes. In this research, Al₂O₃ ceramics pellets weredesigned and manufactured via FDM with different infillstructures i.e., circular, linear, grid and hexagonal tounderstand its hardness and fracture toughness. The 3Dprinted samples showcased a relative density of ~95%whereas cold isostatic pressed (CIP) alumina showcasedonly 87.5%. Also, indentation fracture toughness ofhexagonal alumina (4.49 ± 0.05 MPa.m0.5) which was~40% higher than alumina (3.16 ± 0.08 MPa.m0.5)prepared via CIP. ceramics pellets were designed and manufactured via FDM with different infill structures i.e., circular, linear, grid and hexagonal to understand its hardness and fracture toughness. The 3D printed samples showcased a relative density of ~95% whereas cold isostatic pressed (CIP) alumina showcasedonly 87.5%. Also, indentation fracture toughness of hexagonal alumina (4.49 ± 0.05 MPa.m0.5) which was ~40% higher than alumina (3.16 ± 0.08 MPa.m0.5) prepared via CIP.