Mechanical fracture of lattice structures fabricated by selective laser sintering

Abstract The current study is focused on the static and dynamic behavior of different 3D-printed lattice structures fabricated by selective laser sintering (SLS) technique. To this end, body-centered cubic and face-centered cubic lattice structures were designed and printed using polyamide 12 (PA 12) material. A series of compression tests were performed on the lattice specimens under static loading conditions. We used the conventional split Hopkinson pressure bar (SHPB) at the impact speed of 12 m/s to determine the dynamic behavior of 3D-printed structures under high strain rate. In experimental practices, a high-speed camera was utilized as non-contact optical technique to document the process from initial impact till the specimen failure. In addition, finite element models were developed to determine the dynamic mechanical response of the lattice models. The experimental results indicated that the compressive strength increased with the loading rate. It confirmed the strain rare sensitivity of the studied PA 12. The results of this study can be employed to enhance the design of 3D-printed lattice structures for their further engineering applications.