Effect of Additive Manufacturing Parameters on PLA, ABS, and PETG Strength

Additive manufacturing has emerged as a promising technology to fabricate customized polymer parts, but the mechanical performance of printed components often falls short of bulk material properties. Among the different techniques, fused filament fabrication is the most accessible and widely adopted. However, previous studies addressing its processing parameters have produced fragmented or contradictory conclusions, limiting the ability to establish guidelines for mechanical optimization. This work addresses this gap by systematically investigating the influence of key parameters—extrusion temperature, printing speed, infill type and density, layer height, and number of walls—on the tensile properties of three commonly used thermoplastics: PLA, ABS, and PETG. A total of 495 standardized specimens were produced and tested under controlled conditions. The results demonstrate that increasing infill density and wall number consistently enhances tensile strength, with PLA showing an improvement of 1173 N when infill was raised from 20 to 80%, and PETG doubling its strength from 559 N with one wall to 1207 N with five walls. Layer height also had a positive effect, with PLA rising from 995 N at 0.10 mm to 1355 N at 0.30 mm. In contrast, higher printing speeds reduced mechanical performance (PLA decreased by 13% between 20 and 50 mm·s−1). Temperature exhibited material-dependent trends: PLA benefited up to 230 °C (+17%), while ABS strength decreased beyond 220 °C. Overall, the study provides a quantitative assessment of how processing parameters control mechanical reliability in polymer parts, offering practical guidelines for improved design and manufacturing.