Modeling and optimization of extrusion process parameters for the development of Nylon6–Al–Al2O3 alternative FDM filament

Abstract

The present work focused the detailed investigation on the development of Nylon6–Al–Al2O3-based alternative fused deposition modeling process (FDM) feedstock filament (in lieu of commercial acrylonitrile butadiene styrene filament) by optimizing the process parameters of single-screw extruder (such as composition, mean barrel temperature, and die temperature) in terms of responses (tensile strength and diameter deviation) using response surface methodology. Initially, the suitability of alternative material as an alternative FDM filament has been verified by rheological investigations and the tensile testing (according to ASTM-638 standard). The tensile strength of feedstock filament was significantly affected by the variation of major input parameters during the processing of alternative material on single-screw extruder. A second-order regression equation for each process response (obtained by ANOVA) validates the modeling goodness of fit and selects proper forms of influentially significant process variables (main, two-way interaction, and pure quadratic terms) within 95 % of confidence interval (p value ≤0.05). A multi-objective and multi-response optimization techniques based on the use of desirability function concept have been applied for the response regression equations to simultaneously find a set of optimal input parameters, yielding the maximum tensile strength along with the minimum deviation in feedstock filament diameter. The predicted optimal results were also validated experimentally with an error <4 %. In addition to above, the dynamic mechanical analysis was performed, which indicate that the filament fabricated with optimum combination of parameters have adequate stiffness and is suitable for FDM system.