Experimental and Numerical Thermo‐Mechanical Characterization of Polylactic Acid Fabricated by Fused Filament Fabrication

ABSTRACT This study investigates the thermomechanical response of polylactic acid (PLA) specimens fabricated by fused filament fabrication (FFF) at two nozzle temperatures (190°C and 230°C), while mechanical testing was performed at three temperatures (20°C, 30°C, and 40°C) below the glass transition temperature ( T g ). Quasi‐static uniaxial tensile and compression tests were conducted to characterize the mechanical response under these thermal conditions. The experimental results showed that increasing nozzle temperature improved tensile stiffness and strength. The highest tensile and compressive properties were obtained for specimens printed at 230°C and tested at 20°C, with tensile modulus and tensile strength of 3573 MPa and 54 MPa, and compressive modulus and compressive strength of 1343 MPa and 71 MPa, respectively, indicating anisotropic mechanical behavior. In addition, dynamic mechanical thermal analysis (DMTA) was also performed to evaluate the viscoelastic response and determine T g , including a comparison with injection‐molded PLA. To establish a reliable predictive framework for thermomechanical behavior, experimental measurements were used to calibrate the ANSYS‐Three Network Model (TNM). The resulting numerical simulations of the tensile and compression tests demonstrated good agreement with the experimental results, confirming the capability of the model to predict the thermomechanical response of polylactic acid fabricated by fused filament fabrication.