Influence of Process Parameters on Dimensional Accuracy and Porosity of Additively Manufactured Carbon Fiber Reinforced Polyamide Composite Structures

Engineering design involves selecting optimal materials to meet operational and managerial requirements. Advances in composites technology have led to lightweight, cost-effective materials with superior properties. Fiber Reinforced Additive Manufacturing (FRAM) enables production of composite parts with high mechanical performance, offering high strength-to-weight ratio, design flexibility, and rapid prototyping. Fused Filament Fabrication (FFF) is the most common AM technique, using fiber-reinforced polymer filaments. The properties of short fiber-reinforced composites in FFF are significantly influenced by process parameters. This research is an experimental investigation for the optimization of FFF process variables. Taguchi method (L9 array) for Design of Experiments (DOE) was used in the research to analyze the impact of process variables on volumetric accuracy and porosity of printed parts. Test samples as per ASTM D695 were manufactured using FFF type 3D printer (IEMAI Magic HT Pro). Short Carbon fiber-reinforced polyamide (CF-PA6) filament was used. Four printing parameters at three different levels were used, which are print temperature (260–280 °C), print speed (40–60 mm/s), layer height (0.25–0.35 mm) and raster angle (30°–60°). Porosity evaluation was carried out through optical micrography followed by image processing with ImageJ software. Volumetric deviation was observed in the range of 0.44 ml to 0.87 ml, whereas porosity ranged from 5.50% to 6.416%. Trade-off was observed between minimizing both objective parameters. The study provides valuable insights into optimized FFF printing parameters for achieving dimensional accuracy and porosity control of Fiber Reinforced Polymers (FRPs) produced through AM.