Topology-optimized lattice structures with simultaneously high stiffness and light weight fabricated by selective laser melting: Design, manufacturing and characterization

Abstract

Abstract In this study, the level set-based topology optimization method was adopted to design novel lattice structures. The Ti-6Al-4V topology-optimized lattice structures with 30 % volume of solid materials were successfully fabricated by selective laser melting (SLM). The study on mechanical properties and energy absorption capability of the topology-optimized structures was also conducted through the quasi-static compressive testing. Results showed that as the unit cell number of lattice structures increases, the structural failure mechanism changes from the layer-by-layer fracture to the 45° inclined fracture. Topology-optimized lattice structures have a better relative elastic modulus of 0.037 than that of the majority of reported lattice structures, and the as-designed lattice structures possess relatively high energy absorption efficiency of 67.9 % at 0.15 strain. The findings illustrated that the proposed topology optimization method combined with SLM processing is an effective way to obtain novel lattice structures with high load-bearing and energy absorption capacities.