Quasi-static and dynamic mechanical properties of additively manufactured Al2O3 ceramic lattice structures: effects of structural configuration

Ceramic lattice structures (CLSs) are promising candidates for structural applications used in conventional and extreme environments because of their extraordinary properties. Herein, CLSs with different structural configurations, including body-centred cubic (BCC), Octet, and modified body-centred cubic (MBCC), were designed and fabricated by digital light processing (DLP)-based additive manufacturing technology to explore their quasi-static and dynamic compressive behaviours. It was demonstrated that when relative density was a constant, quasi-static compressive strength (QS), quasi-static Young's modulus (QY), and quasi-static energy absorption (QE) of CLSs with an MBCC structural configuration were the best, Octet ranked secondly, BCC was the poorest. The same thing happened on dynamic mechanical properties of CLSs. Increasing the relative density from 20% to 40% dramatically improved the QS, QY, and QE of CLSs. Furthermore, it was revealed by experiment and simulation that the quasi-static failure mode of CLSs changed from partially fracture along a specific plane to integrally fracture at most nodes as relative density increased. Furthermore, the dynamical mechanical properties of CLSs were significantly outstanding than quasi-static mechanical properties due to the strain-rate effect. This study provides a new basis for further study on tailoring the mechanical properties of CLSs.