Improving the compressive response of bio-polymeric additively manufactured cellular structures via foam-filling: An experimental and numerical investigation

Additive Manufacturing is effective at addressing advanced innovative design requirements for functional applications. Lattice structures and lightweight composites are the result of engineering designs for enhanced mechanical and structural properties. Inspired by nature, this work investigates the static and cyclic compressive response of 3D-printed Triply-Periodic-Minimal-Surface cellular structures made of Poly-(Butylene-Adipate-co-Terephthalate) (PBAT) biopolymer functionalized with Poly-Urethane foam. The plateau stress of the hybrid structure is 30% higher and the specific energy absorption capability 18% higher than the empty structure due to interaction between the two phases. A finite-element model is developed as a supporting tool to analyze, predict, and optimize structural behavior, as well as improve understanding of the deformation mechanisms. In addition, PBAT proves to be the ideal candidate for greener manufacturing, combining good mechanical properties with biodegradability, paving the way for a range of new applications.