Effects of Coating Post-processing on the Compressive Properties of Strut-and-Node-Based FDM Lattice Structures

Lattice structures have many outstanding properties, and their use in diversified industrial and biomedical fields is widely studied. The advent of additive manufacturing (AM) technologies has further pushed the design of these cellular structures allowing for the fabrication of complex trusses and tailored local geometries. However, geometrical defects introduced by the AM process into printed lattice structures significantly affect their mechanical properties. In this work, the effect of chemical post-processing on the compressive properties of FDM-PLA strut-and-node-based lattice structures is evaluated. A UV resin has been used as a coating film on samples fabricated using Simple Cubic (SC) and Face-Centered Cubic (FCC) unit cells. Results demonstrated a 65% increase in compressive strength for SC unit cells and a 12% increase for FCC unit cells with respect to as-printed samples. Resin coating demonstrated to represent an effective approach to minimize defects of strut-and-node-based lattice structures, thus enhancing mechanical properties.