Mechanical responses of Ti 6Al 4V cuboctahedral truss lattice structures
Abstract Ti 6Al 4V cuboctahedral truss lattice structures were manufactured via a combined approach of snap fitting and vacuum brazing. By varying the strut length l from 7.7 to 22 mm, structures of relative densities in the 1.5 7.5% range were fabricated and mechanically tested in compression. Lattice collapse mode transformed from elastic to inelastic truss buckling at a relative density 2.5% corresponding to a strut aspect ratio t l 0.09. The mechanical properties are found to be sample size dependent, and are significantly knocked down in small sized specimens by the soft edges. A low nodal connectivity Z 8 of the cuboctahedral truss topology makes it less efficient to attain the maximum mechanical performance, and nodal fractures preceded the attainment of numerically anticipated lattice peak strength. Nonetheless, mechanical properties of cuboctahedral structures are competitive with existing topologies and materials, and the full potential performance could be achieved in structures with large numbers of in plane cells.