Effects of infill parameter variations on mechanical properties in 3D printed structures: comparative study with fem analysis

This paper investigates the mechanical behavior of 3D-printed Polyethylene Terephthalate Glycol (PETG) and Poly Lactic Acid (PLA). This study aims to provide information on how the mechanical properties of 3D-printed PETG and 3D-printed PLA are affected by the in-fill parameter (printed layer density). Different infill parameters (hereafter named layer density or density) and ply orientation (filament/fiber orientation) are used for obtaining PETG and PLA samples. Values of mechanical properties were recorded at bending tests on specimens with different densities, namely 10%, 15% and 20%, at angles of 0° and 45°, aiming to assess the material's quality about its properties and applications. PETG and PLA exhibited elastoplastic behavior during bending tests. Obtained results indicate that samples made with PLA exhibit superior mechanical properties compared to those made with PETG. The samples bending tests are validated with FEM analysis. PETG-based samples demonstrate higher resilience and elongation at break values, indicating greater flexibility and resistance to deformation. In contrast, PLA-based samples display more brittle characteristics, with elongation values at failure significantly lower by one order of magnitude.