Experimental and numerical investigation of diagonally reinforced 3D-architected polymer honeycomb lattice structures fabricated via FDM using PLA

Abstract

This study introduces a novel hexagonal honeycomb lattice design incorporating integrated diagonal struts, developed to enhance compression strength and energy absorption in 3D-printed polymer structures. Five distinct lattice configurations were fabricated using polylactic acid (PLA) filament and evaluated through uniaxial compression testing. The results showed that Lattice 5, which features a hexagonal unit cell with diagonal struts from top left to bottom right, had the highest compression strength of 45.78 MPa and absorbed 14,406 J of energy. In comparison, Lattice 1, with a regular hexagonal unit cell, had 15 % lower compression strength and 20 % lower energy absorption. Analytical models based on honeycomb geometry and PLA material properties were used to predict how the structures would deform. Finite element analysis (FEA) was also conducted to study the deformation under dynamic loading, with Lattice 5 proving to be the most efficient design. The diagonal struts in Lattice 5 helped to redistribute the load more evenly, reducing stress concentrations and allowing for a more gradual deformation. The FEA results matched the experimental data closely, confirming the accuracy of the predictions. These findings offer useful insights for improving lattice structures for applications that require high performance in terms of both structural strength and energy absorption.