Effect of unit cell topologies on mechanical properties of cylindrical lattice structures fabricated by indirect additive manufacturing

Due to the vast potential of lattice structures in many fields such as automotive, aerospace, and biomedical industries, they have become an intriguing subject for research with numerous parameters available for investigation. While conventional lattice designs have predominantly utilized cubic geometries, limited research has explored cylindrical geometries. In this paper, AlSi10Mg hollow cylindrical lattice structures with three different novel strut base cell topologies (FCCxyz, BCCxyz, and Auxetic) are designed and fabricated using the indirect additive manufacturing method. Quasi-static compression tests are conducted to evaluate their mechanical performance and deformation behaviors. Key mechanical properties are extracted and compared across the three topologies. Microstructural analysis is conducted to assess the impact of the fabrication process on material characteristics. The results revealed that FCCxyz structures exhibited superior mechanical performance and weight efficiency. Auxetic structures, while demonstrating the lowest values for most mechanical properties, outperformed BCCxyz structures in terms of energy absorption and plateau stress. Through the compression process, all structures showed brittle deformation behavior which is the result of the presence of plate-shape Si and Chinese script-like phases in the microstructures. The deformation mechanism for all structures primarily involves layer-by-layer failure, with the formation of shear bands in structures with BCCxyz and FCCxyz unit cell topologies. the deformation behavior of the studied structures is closely similar to those typically occur in cubic structures. In this study, typical topologies have been extended to use in hollow cylindrical geometry that should open up new perspectives in the research field of lattice structures.