Effects of print parameters on tensile characteristics of additively manufactured polyethylene terephthalate-glycol (PETG)

Determining the mechanical characteristics of additively manufactured materials has been an active topic of research in recent years. Many studies have been performed analyzing the impact of different 3D print parameters on the tensile properties of the printed material. However, compared to typical metals and polymers, there is no widely adopted standard for testing additively manufactured polymers. Consequently, the test results reported by the researchers in this field exhibit high amounts of variability between studies. A set of consistent experiments across five different printing parameters including build orientation, raster orientation, infill type, infill density, and layer thickness was carried out in the present paper. The results were analyzed to look at trends between the tested variables and the yield strength and elastic modulus of the resultant additively manufactured polyethylene terephthalate-glycol (PETG). Build orientation, raster orientation, infill type, and infill density all showed strong relationships with the tensile properties. Layer thickness showed little variation across the typical range for a given extrusion width. Previously developed experimental models were also checked and showed that even small variations in other parameters such as raster gap or extrusion factor could create significant enough variation to make the model inaccurate for a specific scenario.