Enhancing the mechanical properties of FDM 3D printed PETG parts with high pressure cold isostatic pressing

Abstract

This study examined the effects of cold isostatic pressing (CIP) as a post-processing method for polyethylene terephthalate glycol-modified (PETG) parts produced by fused deposition modeling (FDM) 3D printing. To analyze the mechanical properties of CIP, 3D printed specimens were subjected to CIP at pressures ranging from 250 to 1000 bar with holding times of 1 to 10 min, followed by tensile, flexural, and interlaminar shear strength tests. Scanning electron microscope (SEM) and X-ray diffraction (XRD) analyses were performed for morphological and chemical property changes. The mechanical properties were generally optimal at 500–750 bar, indicating a significant improvement. SEM analysis revealed that the interlayer gaps and void areas decreased, with the porosity reduced by 4.46 times compared to the untreated samples. XRD analysis showed that the CIP treatment did not significantly alter the chemical structure of PETG and maintained its amorphous characteristics. These results suggest the potential of CIP as an effective post-processing technique that improves the mechanical properties while preserving the basic material characteristics of FDM-printed parts.