Revealing Anisotropic Properties in Material Extrusion/Polylactic Acid through Multiplane Printing

Abstract Material extrusion, also known as fused filament fabrication (FFF), is a key technology in three-dimensional (3D) printing technology for creating plastic components. Despite its popularity, the anisotropic behavior affecting the mechanical performance of FFF parts remains a challenge. This research delves into the influence of multiplane layering on the mechanical and physical properties of PLA-FFF printed parts. Comprehensive tests, including tensile, bending, and relative density measurements, were executed, focusing on build orientation and infill patterns. The results highlight the paramount importance of building orientation: multiplane (0°, 0°) with concentric and line patterns displayed superior tensile strengths of 52.5 and 51.0 MPa, respectively, outperforming the single-plane strengths of 35.2 and 30.2 MPa. Similarly, for bending, multiplane layering in both patterns surpassed single-plane results, achieving 88.8 and 88.3 MPa compared to 42.8 and 46.0 MPa. The study conclusively demonstrates that multiplane layering elevates the mechanical and physical properties of FDM prints in the Z orientation, mitigating voids and approaching isotropic strength. Therefore, multiplane layering emerges as a potent strategy to counteract the inherent anisotropy of FDM prints, enhancing their mechanical properties.