Optimization of 3D Printing Parameters on Mechanical Properties of Printed PETG Materials

Abstract

Polyethylene terephthalate glycol (PETG) is gaining popularity as a 3D printing material, replacing traditional polymers like PLA and ABS in various industries such as medical and automotive. Despite the growing popularity of PETG as a 3D printing material, the relationship between its mechanical properties and the specific printing parameters used has not been comprehensively studied. Therefore, this research aims to investigate the influence of 3D printing parameters, namely layer thickness, raster angle, and infill density, on the flexural and impact strength of 3D printed Polyethylene Terephthalate Glycol (PETG). Response Surface Methodology (RSM) was employed for experimental design through the Box-Behnken Design (BBD) method. The 3D modelling was created according to ASTM standards then sliced using Ultimaker Cura software. Subsequently, the models were printed and underwent mechanical testing to evaluate its flexural strength using a Universal Testing Machine (UTM) and impact strength using an Izod impact apparatus. The results through ANOVA analysis demonstrated that high layer thickness and infill density significantly enhance impact strength. Conversely, reducing layer thickness at high infill density improves flexural strength. Raster angles have less significant influence on both flexural and impact strength. The optimal printing settings for PETG obtained were layer thickness of 0.234 mm, an infill density of 80%, and a raster angle of 90 degrees. These parameter settings result in a 31.9 MPa in flexural strength and 34.7 MPa in impact strength. Confirmation runs validated the model with a low error rate of 10%. Therefore, this research contributes to the advancement of additive manufacturing by providing guidelines for optimizing PETG-based 3D printed objects, enhancing their reliability and durability for various industrial applications.