Investigation on tensile strength and failure modes of FDM printed part using in-house fabricated PLA filament

Fused deposition modelling (FDM) is the extensively used additive manufacturing technology because of its ability to make specimens having a complicated geometrical shape in a decent amount of time. In the present research work, the entire filament fabrication sequence is analysed, starting with the polymer granules, filament production by an extrusion process and test specimen printing. Polylactic acid (PLA) granules were used to fabricate the filament using a single screw extruder. Then after, this in-house fabricated PLA filament was used to make tensile specimens using an open-source FDM machine. Tensile testing was carried out to analyse the tensile properties of FDM printed PLA parts. The influence of the FDM processing parameters viz. raster angle, layer thickness and raster width have been investigated. It has been observed that the raster angle is a significant parameter for tensile strength. Further, a scanning electron microscope (SEM) analysis has been carried out to study various failure modes.