Evaluating mechanical strength of three dimensional printed PLA parts by free form fabrication

The present work focuses on the effect of some parameters on the mechanical properties of poly-lactic acid (PLA) based 3D printed parts. The study was conducted using input parameters like infill density (60% & 90%), annealing temperature (80 degrees C and 120 degrees C), and range of layer thickness from 0.2 mm to 0.4 mm. The prepared specimens were subjected to tensile testing for evaluating tensile strength, yield strength; etc based on different parameter combinations. It was observed that 90% infill density exhibits higher strength as compared to 60%. Also, increasing the annealing temperature results in minor increase of the strength but at the expense of ductility and mechanical strength is higher for low values of layer thickness. Scanning electron microscopy was also performed to analyze the behavior of fractured surface of the tensile tested parts. The results show a strong dependence of mechanical properties on layer thickness and infill density. (c) 2019 Elsevier Ltd. Selection and Peer-review under responsibility of the scientific committee of the International Mechanical Engineering Congress 2019: Materials Science.