Ventilated surface-based lattice structures designed for polymer powder bed fusion process

This work addresses the issues of entrapment of polymer powder and the post-processing powder removal challenges in surface-based lattice structures 3D printed with powder bed-based additive manufacturing (AM) technology. A ventilation design approach has been proposed to enhance the powder removability from the widely researched three-dimensional gyroid and two-dimensional honeycomb lattice structure. The flow characteristics and mechanical behavior of the designed lattices were analyzed using computational fluid dynamics (CFD) and finite element analysis (FEA), respectively, followed by experimental powder flow and compression testing. HP jet fusion 4200 (R) industrial 3D printer was used for printing the lattice structures for experimental validation. The results showed a 65-85% improvement in powder flowability, with a minimum to severe reduction in mechanical strength of different lattice structures. The study can be applied to designing products with multi-functional properties with surface-based lattice structures by employing the principle of design for additive manufacturing and post-processing (DfAM&PP).