How Surface Roughness Performance of Printed Parts Manufactured by Desktop FDM 3D Printer with PLA+ is Influenced by Measuring Direction

Design work related to the implementation of new elements requires the use of 3D CAD modelling techniques and rapid prototyping, which makes it possible to accelerate the deployment of new solutions significantly. In this paper, six successful assembly parts are 3D printed with advanced polylactic acid (PLA+) using the fused deposition modeling (FDM) method and are expressed by the arithmetic mean surface roughness, Ra. The surface roughness was measured in three different angular directions 0°, 45° and 90° during the investigation along with various independent process parameters of nozzle diameter (0.5, 0.3, 0.2 mm), layer height (0.3, 0.2, 0.1 mm) and other dependent variables, i.e., nozzle temperature (220°C), print speed (30 mm/s) and infill density (0%). Experimental results show that nozzle diameter and layer height play a major role in terms of part quality finish, build time and ultimately part cost. Nozzle diameter and a layer height of 0.3 mm and 0.1 mm, respectively, represent the optimal manufacturing process parameters that can be selected. The surface roughness behaviour does not change and remains relatively constant and follows a similar trend with minor variations for both 45° and 90° measuring angle. Whereas, the surface roughness values are susceptible to 0° measuring direction to the build orientation as compared to other angles.