Mechanical properties and failure behaviour of architected alumina microlattices fabricated by stereolithography 3D printing

• Alumina microlattices with solid struts were fabricated stereolithography 3D printing . Specific stiffness and specific strength of the best for Simple Cubic design, followed by Octet Truss Kelvin Cell designs. lattices failed column from boundaries into center while fractured along diagonal (110) plane. At low relative densities, microlattice sequentially, due to truss buckling, at high simultaneously. Because alumina has asymmetric in compression (2.3 GPa) tension (0.3 GPa), fractures tend initiate localized regions lattices, which developed despite being compressed globally. The exhibited excellent moduli their mass densities even demonstrated some degree ductility (pseudoplastic strain ~ 0.1% - 0.5%). different topologies method. Mechanical analysis shows that highest Truss, then lattices. mechanical properties Ashby's power law well small (≤ 0.3), but deviated it higher increased importance joint deformation. Failure proceeded a column-by-column manner inwards centre, fracture took place predominantly (111) planes respectively. underlying mechanism controlling these responses been thoroughly discussed using finite element simulation analysis. lattice was limited tensile alumina, an order magnitude lower than its compressive strength, weaker predictions. Nevertheless, they still able exhibit better modulus many current engineering materials, as form pseudoplastic strains (0.1 % 0.5 %).