Influence of printing speed, layer thickness, and infill percentage on the mechanical properties of 3d-printed pla filament for prototyping

Abstract

Proper selection of infill density, printing speed, and layer thickness could conserve material use, reduce printing time, and give acceptable mechanical properties for prototyping. Previous research has emphasized infill density as the major influencer on mechanical properties in additive manufacturing because a wider range of values is usually considered. However, for this study, 15 %, 17.5%, and 20 % infill densities used in prototyping; 60 mm/s, 70 mm/s, and 80 mm/s printing speeds; and 0.1 mm, 0.2 mm, and 0.3 mm layer thicknesses were selected. Twenty-seven samples were derived based on the Taguchi orthogonal array with three factors and nine runs, and a tensile test according to ASTM D638 was performed on each. Statistical and regression analysis was done to investigate the influence of each of the parameters on maximum tensile stress, load at maximum tensile stress, and modulus respectively for each sample and present a model for further parameter investigation. Printing speeds of 60 mm/s and 80 mm/s gave the highest mechanical properties with layer thicknesses of 0.1 mm and 0.2 mm. The sample with 70 mm/s printing speed at a layer thickness of 0.1 mm has the lowest modulus of elasticity. Lower and medium printing speeds and layer thickness showed higher tensile stress and modulus of elasticity.