Effect of Filling Ratio-Pattern Parameters on Mechanical Properties of PLA Filaments Used in 3D Printing

Abstract

This research primarily focuses on the mechanical properties of specimens produced using Polylactic Acid (PLA) through the Fused Deposition Modeling (FDM) technique, a method of 3D printing. Within the scope of this study, specimens were fabricated using various fill percentages and different infill patterns. The simultaneous effect of variable parameters on mechanical properties is a challenging task, and it is aimed to rank the importance of the parameters, model the process, and finally validate the models using tensile and bending experiments. The results show that samples with a Concentric pattern and 95% fill rate exhibited the highest tensile strength with an average of 48.67 MPa. In contrast, the Triangle pattern with 20% infill ratio showed the lowest tensile strength with an average of 14.15 MPa. When evaluating flexural strength values, the Concentric design with a 95% fill ratio stood out once again, recording an average peak value of 79.94 MPa. Meanwhile, the Honeycomb pattern at 20% infill ratio exhibited the lowest strength value measured with an average of 23.3 MPa. Scanning Electron Microscope images taken according to infill rates confirm each other with the voids formed and mechanical performance outputs. These findings underscore that the mechanical attributes of PLA specimens produced using 3D printing technology can significantly vary based on the chosen fill rate and pattern.