D-optimal-based parametric study for improving the FFFed product quality of the ABS material

This work studied the influence of process parameters (i.e., numerical factors, such as printing speed, immersion time, and built platform temperature; categorical factor, such as plane orientation type) on fused filament fabrication (FFF) process. The experimental study was conducted using a D-optimal four-factor design (three numerical and one categorical) design based on the response surface methodology. Samples were fabricated on an FFF machine, and tests were conducted to measure volumetric shrinkage and surface roughness. The experimental data were evaluated through analysis of variance and fitted to a second-order polynomial equation using the multiple regression method. The optimal conditions for minimizing both responses were identified by numerical optimization using the desirability function approach. Finally, a confirmatory analysis was performed using optimized parameter values that demonstrated a strong response to the predicted model. Under optimal conditions, the SEM micrographs of the cut surface revealed a decrease in distortion. Findings demonstrated that the response surface methodology based D-optimal approach was effectively utilized for modeling FFFed specimens and proved to be cost-effective in collecting the highest amount of information in the shortest period of time with the fewest possible number of experimental tests.