Alexandra Llidó Barragán, Aritz Unamuno Garay, Santiago Ferrándiz-Bou, Dana Luca Motoc, Cristina Pavón
Additive manufacturing, particularly Fused Deposition Modeling (FDM), has emerged as a promising technology for construction applications due to its ability to fabricate complex geometries, optimize material usage, and enable customized designs. This study investigates the effects of different infill patterns and densities on the compressive behavior of polylactic acid (PLA) specimens to identify suitable configurations for industrial applications. Cubic specimens (50 mm × 50 mm × 50 mm) were designed in SolidWorks, sliced with PrusaSlicer using various conventional and bio-inspired infill patterns, and manufactured using a Prusa i3 MK3S printer. Compression tests were conducted to evaluate stiffness, strength, toughness, and deformation capacity. In addition, finite element method (FEM) simulations were carried out to predict the mechanical response under compressive loading. The results showed that the honeycomb infill pattern provided the best overall performance, combining moderate stiffness with high deformation capacity, reaching strains of approximately 40% before failure, and exhibiting superior energy absorption. Among the tested configurations, an infill density of 20% offered the best balance between mechanical performance, material consumption, and printing time. These findings demonstrate that honeycomb-based structures with moderate infill densities are promising candidates for lightweight engineering applications requiring high energy dissipation and damage tolerance.