ABSTRACT This study investigates how two key 3D printing parameters—infill density and layer orientation—affect the mechanical behavior of PLA specimens produced using Fused Deposition Modeling (FDM) under tensile loading. Standardized tensile samples were designed per ISO 6892‐1 in CATIA V5 and printed using Crealty software, with infill density set at 30%, 60%, and 90%, and layer orientation varied in three directions (A, B, and C). All other printing settings, including extrusion temperature, speed, and linear infill pattern, were kept constant to isolate these variables. Mechanical performance was evaluated through Digital Image Correlation (DIC), a precise optical method for measuring strain and deformation. Results showed that higher infill density increased stiffness and tensile strength, while the layer orientation had a significant impact on failure behavior. Specimens printed in C orientation, where filament layers aligned with the tensile direction, demonstrated superior strength and uniform stress distribution. Conversely, A orientation samples failed prematurely due to delamination and crack initiation at interlayer boundaries. Overall, the study highlights that optimizing infill density and layer orientation is essential for enhancing the structural integrity and functional performance of FDM‐printed PLA components.
Tălîngă et al. (Fri,) studied this question.