Fused Deposition Modeling (FDM) is a kind of Additive Manufacturing technology, which can produce complex parts by adding layer-by-layer mold automatically from 3D computer-aided design (CAD) data. Although the FDM process has its obvious merits, a fundamental backward factor of its professional enterprise acceptance is the inadequacy of higher mechanical properties and heavy structure of the manufactured product. For that reason, the properties of the manufactured product by FDM are highly dependent upon the choice of FDM parameters. Several studies are investigated to look at the effect of various FDM process parameters to improve print quality characteristics such as mechanical properties, build time, dimensional accuracy, and surface finish of the manufactured parts with having convenient process parameter settings. However, the progress has been gradual and not well organized because of the complex attributes of the FDM process and conflicting process parameters. This paper aims to comprehensively summarize recent studies of advanced statistical and experimental design techniques for better tensile strength of polylactic acid (PLA)-printed parts, the effect of process parameters on tensile strength, and the existing work on the optimization of process parameters.

In this work, the combined effects of fused filament fabrication (FFF) process parameters on the mechanical properties of 3D printed PLA products have been determined by focusing on the tensile strength at R 2 (97.29%). ASTM D638 test standard is used for the preparation of specimens for tensile tests. The optimization technique has been used to determine the optimal combinations of FFF process parameters for the validation of experimental tensile tests and computational fluid dynamics (CFD) simulations. From the results obtained the optimum cooling fan speed of 79.3%, extrusion temperature of 214.4 °C, printing speed of 75.9 mm/s, raster width of 0.4814 mm, and shell number 5 were determined with a 2.266% error of the tensile strength (45.06 MPa). SEM morphology examination shows that the fabricated part cooled at 80% cooling fan speed illustrates good inter-layer bond strength which is also confirmed by CFD temperature distributions analysis.