Effect of infill pattern on the mechanical properties of PLA and ABS specimens prepared by FDM 3D printing

Fused deposition modelling (FDM) is a three-dimensional printing technique which has become more popular and spreading in many fields. In this process, the molten thermoplastic is deposited layer by layer using a heated nozzle. Users can set the infill pattern to save the material and printing time. The main objective of this study is to investigate the tensile properties of polylactic acid (PLA) and Acrylonitrile butadiene styrene (ABS) tensile specimens with different infill patterns such as lines, tri-hexagonal and lightning. Further, the test specimens were prepared as per ASTM D638 using Ender 3D printer with varying infill patterns. The specimens were subjected to tensile tests in a mechanical tensile testing machine. It was observed that the specimens with linear infill patterns obtained higher tensile strength than the tri-hexagonal and lightning pattern infilled specimens. Later on, a microstructural study was examined on the fractured surface using scanning-electron-microscopy (SEM). It shows that the line pattern specimens have more uniform structure when compared to hexagonal and lightning pattern specimens.