THE EFFECT OF FDM PROCESS PARAMETERS ON THE MACHINABILITY OF PET-G MATERIAL: DELAMINATION ANALYSIS USING THE TAGUCHI APPROACH

In this study, the machinability of PET-G (Polyethylene Terephthalate Glycol) material produced by Fused Deposition Modeling (FDM) was experimentally investigated under various manufacturing and machining parameters. The effects of key parameters influencing delamination—namely infill percentage, layer thickness, spindle speed, and feed rate—were specifically examined. Statistical data were obtained using the Taguchi method, and the results were analyzed in terms of both mean values and Signal-to-Noise (S/N) ratios. The findings revealed that infill percentage has a significant effect on delamination. The lowest delamination values were observed at a 100% infill level, while the highest delamination occurred at a 33% infill ratio. When layer thickness was increased from 1 mm to 2 mm, a reduction in delamination tendency was observed. An increase in spindle speed resulted in a notable rise in delamination, particularly at high rotational speeds (4500 rpm), where elevated cutting forces and temperature led to structural damage and delamination. The influence of feed rate on delamination was relatively minor. This study presents a comprehensive experimental analysis of both production parameters (infill percentage and layer thickness) and machining parameters (spindle speed and feed rate) for PET-G material. It is concluded that, for optimal machinability of PET-G manufactured via the FDM method, an infill percentage of 100% and a layer thickness of 2 mm are recommended. This work provides valuable guidance for quality control and parameter optimization in post-additive manufacturing machining processes.