Computational analysis of the extrusion process of fused deposition modeling of acrylonitrile-butadiene-styrene

Die swelling is one of the paramount factors that impresses dimensional accuracy and quality of functional parts in Fused Deposition Modeling (FDM), one of the most famous Additive Manufacturing (AM) processes. Die swelling is considered a critical phenomenon in polymer extrusion process affected by melt flow rate, extruder temperature and its geometry. In this research, the ABS melt polymer behavior in the extrusion process of FDM and the die swell of extruded polymer have been investigated by empirical experiments and simulated by the Finite Element Method (FEM) using rheological properties of ABS. The internal geometry of the nozzle is investigated via analytical simulation and finite element analysis to obtain pressure and velocity distributions of the material inside the extruder as well as the die swell of extruded filament. Additionally, experiments were carried out to validate the analytical and numerical simulations. The results showed that higher melt temperature and lower material flow rate result in less pressure drop inside the nozzle and less swelling of the extruded filament.