Investigating the effect of build orientation on surface roughness and build time using Fused Deposition Modelling

The advancement of AM technologies has resulted in producing parts of high quality and reduced manufacturing time. The purpose of this study is to simultaneously optimize the values of two response variables, build time and surface roughness. In order to achieve the best values for build orientation and other process parameters including raster width, layer thickness, infill percentage, and raster angle, the effects of process parameters and response variables were adopted by the Design of Experiments approach to develop empirical models using Response Surface Methodology. The experimental parts of this research were conducted using an inexpensive and locally assembled FDM machine. Fifty runs for two different geometries, namely cylinder and 3DBenchy, were performed using the Rotatable Central Composite Design, and each process parameters was investigated in two levels in order to develop empirical models. Also, a novel optimization method, namely, the Posterior-Based method, was accomplished to find the best values for the response variables. The results demonstrated that not only build orientation and layer thickness have notable effects on both response variables but also build time is dependent on raster width and infill percentage. This study shows that through adopting the developed model by considering the process parameters, parts of high quality (improved surface finish) with reduced build time could be produced by FDM technology. Optimum process parameters found to be build direction of 0°, raster width of 0.61 mm, layer thickness of 0.22 mm, infill percentage of 20%, and raster angle of 0°.