An investigation into the layer thickness effect on the mechanical properties of additively manufactured polymers: PLA and ABS

Abstract 3D-printed artefacts are becoming more common, and the effect of printing parameters on their properties is key to their performance in applications. Although parameters like build orientation and raster direction are well-studied the effect of layer thickness is less well-known. This study determines the influence of layer thickness on the mechanical properties of polylactic acid (PLA) and acrylonitrile butadiene styrene (ABS) 3D printed specimens made with fused filament fabrication (FFF). Samples were printed with differing layer thicknesses and tensile tested according to ASTM D638. The study also found that when increasing the layer thickness the mechanical properties of the specimens for both ABS and PLA decreased. When it came to ultimate tensile strength, the effect of layer thickness on PLA was more significant than on ABS. Considering the mechanical properties as well as aspects such as printing time and simplicity of printing, an optimum print setting could be determined. The study found that PLA was more significantly affected by the change in layer thickness compared to ABS.