Comparative Experimental Study on the Compressive Performance of FDM-Printed PLA and ABS Using Different Infill Architectures

Abstract

This study presents an experimental investigation into the compressive behaviour of components fabricated by Fused Deposition Modelling (FDM) using polylactic acid (PLA) and acrylonitrile butadiene styrene (ABS). The mechanical performance of FDM-printed parts is strongly influenced by internal infill architecture; however, limited experimental data exist comparing compressive responses under identical processing conditions. To address this gap, cube specimens with dimensions of 50 × 50 × 50 mm were designed and manufactured using ten different infill patterns at a constant infill density of 40% and a layer height of 0.2 mm. All samples were printed using the same printer and slicing parameters to ensure consistency. Compression tests were conducted using a Universal Testing Machine to evaluate load–crosshead travel behaviour and compressive strength. The results demonstrate a significant dependence of compressive performance on infill geometry for both materials. For PLA specimens, the grid infill pattern exhibited the highest compressive strength, followed by trihexagon and triangle patterns. In contrast, ABS specimens achieved maximum compressive strength with the trihexagon infill, while cubic and gyroid patterns also showed favourable performance. Simple infill geometries such as concentric and line patterns consistently resulted in lower compressive strength for both materials. Overall, PLA samples exhibited higher compressive strength than ABS under identical printing conditions, whereas ABS showed greater deformation prior to failure, indicating a more ductile compressive response. The findings confirm that infill architecture plays a critical role in determining the compressive behaviour of FDM-printed components and provide practical guidelines for selecting suitable infill patterns in load-bearing applications.