Physical Evaluation of FDM-printed Carbon Fiber Reinforced PLA: Mechanical Strength, Moisture Sensitivity, and Porosity

This study investigates the physical properties of short carbon fiber reinforced polylactic acid (SCFR-PLA) specimens produced by fused deposition modeling (FDM). The influence of fiber content, raster angle, and printing speed on mechanical, hygroscopic, and microstructural behavior is analyzed. Printing at a 0⚬ raster angle provides maximum stiffness and tensile strength, while higher speeds enhance strength and ductility but reduce stiffness. Carbon fiber addition improves stiffness, strength, and moisture resistance. SEM analysis reveals pore morphology, linking porosity to mechanical and hygroscopic variations. Correlations among fiber-matrix adhesion, voids, moisture uptake, and durability are also discussed.