The quasi-static and blast response of steel lattice structures

Lattice structures based on two simple architectures have been manufactured from 316L stainless steel using the selective laser melting process. The compressive properties of structures based on a body-centered cubic (BCC) and a similar structure with vertical pillars (BCC-Z) were initially investigated at quasi-static rates of strain. Blast tests were subsequently performed on the lattice structures as well as on lattice sandwich structures with CFRP skins. When subjected to quasi-static compression loading, the BCC structure exhibited a progressive mode of failure, whereas the BCC-Z lattice deformed in a buckling-dominated mode of collapse. The blast response of the lattice cubes exhibited a linear dependency on the applied impulse up to the threshold for material densification. Relationships between the blast resistance and both the yield stress and energy absorption characteristics of the lattices have been established and an examination of the failed samples indicated that the collapse modes were similar in both the quasi-static and blast-loaded samples. Finally, the failure modes observed in the blast-loaded sandwich panels were investigated and found to be similar to those observed in the lattice blocks.