Evaluation of topology-optimized lattice structures manufactured via selective laser melting

Selective laser melting (SLM) technology can manufacture complex lattice structures, which effectively reduces the manufacturing constraint and significantly increases the design freedom for lattice structure. In this study, additive manufacturing and topology optimization are combined for designing Face Centre Cube (FCC), Vertex Cube (VC), and Edge Centre Cube (ECC) structures, which are manufactured via SLM technology. Mechanical performance is evaluated, and a Gibson-Ashby model is developed to predict the performance of the three structures including different levels of porosity. The results show that FCC and VC lattice structures have better mechanical behaviour compared with that of the ECC lattice structure; however, their energy absorption efficiency is inferior to that of the ECC lattice structure. Comparisons between various SLM built lattice structures made from 316L stainless steel prove that the performance of topology-optimized lattice structures is superior to the majority of lattice structures. This result verifies the feasibility of lattice structure unit selection via topology optimization technology. Various work conditions are simulated for topology optimization to obtain a lightweight lattice structure with optimal performance under specific conditions.