Deformation and failure behaviour of Ti-6Al-4V lattice structures manufactured by selective laser melting (SLM)

Selective laser melting (SLM) enables the manufacture of lattice structures with highly engineered mechanical properties that are optimised for the associated design requirements. Such lattice structures offer high specific strength and stiffness characteristics allowing design freedom beyond the capacity of solid materials. However, to apply lattices as space filling structural elements, it is necessary to quantify their mechanical properties such as compressive strength and stiffness under varying geometric conditions. This work provides an experimental investigation of the manufacturability of SLM Ti-6Al-4V lattice struts of varying diameter and inclination. From this investigation, lattice structures are manufactured for varying cell topology, cell size, number of unit cells and associated boundary conditions. The deformation and failure behaviour of these lattices is theoretically predicted and experimentally validated. The convergence of mechanical properties with increasing number of unit cells, as well as the effect of lattice topology on mechanical behaviour and observed failures mode are reported.