Optimization of Printing Parameters of PLA and ABS Produced by FFF

In this study, the changes in tensile strength of PLA and ABS specimens, the most commonly used materials in additive manufacturing with FFF, were investigated as a function of fill rate and print speed. Tensile specimens were fabricated for different fill rates and speeds and tensile tests were performed. Increasing the fill rate increases the tensile strength. Increasing or decreasing the print speed too much has a negative effect on tensile strength. Filament usage and printing times were also calculated. With the data obtained, an optimization model was created using response surface methodology. The aim of this study is to optimize the strength/cost of ABS and PLA, the two preferred FFF materials. The novelty of the study is to investigate the strength/cost optimization for different material types in terms of UTS, filament consumption and printing speed. For each material type, high tensile strength, low printing time and low filament used conditions were determined for the optimization model. The optimum parameters for PLA are obtained at 66.77% fill level and 78.43% speed rate. For ABS, optimum values are obtained at 79.5% fill rate and 135% speed rate. Then, samples were produced for optimum conditions and experiments and calculations were repeated. The numerical results obtained with the model were compared with the experimental results. It is found that the model estimates the output parameters with high accuracy. This proves the accuracy of the proposed optimization model.