Parametric Study in Co-Extrusion-Based Additive Manufacturing of Continuous Fiber-Reinforced Plastic Composites

The main objective of this research is to investigate the newly designed geometry and process parameters in a dual matrix composite filament co-extrusion technology (CFC), a co-extrusion of continuous carbon fiber pre-impregnated with thermoset (1.5K) also known as composite carbon fiber (CCF) filament with a special binder thermoplastic filament. Accordingly, non-isothermal fluid flow and particle tracking analysis were employed in order to examine the melt flow dynamics. In addition, critical parameters like pressure drop, velocity, shear stress, residence time, and swelling/shrinkage ratio were evaluated. In particular, the computational fluid dynamics (CFD) simulations indicates distress in the conventional die design, recirculation and stagnation of melt flow in the dead zones causing longer melt residence leading to the thermal degradation of thermoplastic material. Furthermore, a new print head was designed to expedite the solution for the possible flow instabilities that may lead to a disparity in the material and mechanical properties, a side- fed mandrel die was used as a melt distributor. Consequently, the side- fed mandrel die ensured a homogeneous melt distribution inside the CFC print head, particularly at the die exit.