Effects of fused filament fabrication parameters on the tensile performances of polyethylene terephthalate-glycol (PETG)

Fused filament fabrication (FFF) has been greatly employed in several fields due to the advantages: ease to set up, low production cost, minimum waste, and design flexibility. However, the limited mechanical performances of FFF-fabricated specimens struggled this technique employed in building and some specific engineering applications. Meanwhile, some materials with great recyclability and human harmlessness, including polylactic acid (PLA) and polyethylene terephthalate (PETG), have proved their feasibilities under FFF. Hence, this technique was employed here to fabricate 18 batches of tensile bars under Taguchi’s design of experiment (DOE) methodology to investigate the effects of FFF parameters on the tensile performance of PETG material. The study found some main parameter settings could vary the tensile behaviors of fabricated specimens, where the combination of 250 °C extrusion temperature, 45 mm/s printing speed, 75% infill density led to the greatest tensile performances for specimens fabricated under 0° building angle (44.4 MPa for tensile strength, 829.8 MPa for Young’s Modulus, and 6.7% maximum strain at fracture) and those fabricated under 45° building angle (tensile strength for 49.4 MPa, Young’s Modulus for 891.2 MPa and the maximum strain at fracture for 7.3%), respectively. A computed tomography (CT) Scanner was employed here to verify the results based on the voids in specific batches. This article shows a foundation in the future work related to the additive manufactured PETG specimens, where more processing parameters (layer thickness, building platform temperature, extrusion speed, and the nozzle diameter) can be involved in.