Shock response of sandwich panels with additively manufactured polymer gyroid lattice cores

This work evaluates the shock response of sandwich structures with gyroid lattice cores made from Polylactic Acid (PLA), Acrylonitrile Butadiene Styrene (ABS), and Thermoplastic Polyurethane (TPU) using shock tube experiments coupled with high-speed photography and digital image correlation (DIC). The study found that gyroid lattice structures exhibit high energy absorption capacity and good structural integrity under shock loading, making them suitable for high strength-to-weight ratio and energy absorption applications in aerospace and defense industries. The sandwich panel with a TPU-core structure exhibited the highest deformation under shock loading, with a maximum deflection of approximately 6 mm, followed by ABS at 0.9 mm and PLA at 0.82 mm. Under shock loading, the sandwich panel with TPU gyroid core exhibited the highest specific deformation energy (0.146 J/g), which is consistent with its flexibility, though it remained in the same general order as ABS (0.104 J/g) and PLA (0.070 J/g). Interestingly, the specific total energy of the TPU gyroid core sandwich, while the lowest at 39.310 J/g, was still relatively close to ABS (54.098 J/g) and PLA (52.620 J/g), despite the substantial difference in inherent stiffness of TPU compared to ABS and PLA. This suggests that while TPU's stiffness is much lower compared to PLA and ABS, its total energy absorption capability in gyroid form is not as drastically reduced, indicating the importance of geometry and mass distribution within the gyroid structure. Overall, the results of this study highlight the importance of careful design and optimization of these structures to utilize their unique properties fully.