Investigation of the mechanical properties of 3D printed polylactic acid fabricated by fused deposition modeling technique

The use of 3D printing technology, especially the fused deposition manufacturing (FDM) technique, is expanding across both industrial and private sectors. Given the wide range of potential applications for components produced using this method, there is a growing demand for research into new approaches to improve mechanical properties. In this study, the polylactic acid (PLA) materials are produced using the FDM technique. The effects of various process parameters on the tensile and impact strengths of PLA samples are investigated. In the experiments, variables such as the layer thicknesses of 0.12 - 0.16 - 0.20 mm, occupancy rates of 20% - 40%–60%, printing speeds 20 - 40 - 60 mm/s, and filling structures of triangle, grid and honeycomb are analyzed. The Taguchi method of design of experiments (DOE) is used to analyze the results. Based on the findings, the occupancy rate is the most influential factor, compared with layer thickness, printing speed, and filling structure, in enhancing both the tensile strength at a 55% ratio and the impact strength at a 32% ratio of the 3D printed PLA pieces. The maximum tensile strength is obtained with the honeycomb filling structure, a feeding speed of 20 mm/s, a layer thickness of 0.20 mm, and an occupancy rate of 60%. The optimal results for an impact test are achieved with a layer thickness of 0.12 mm, an occupancy rate of 60%, a printing speed for moves of 60 mm/s, and a triangle filling structure. ANOVA showed that the parameters used interacted with each other.