Analysis of Microstructural and Wear Mechanisms for 3D-Printed PET CF15 Using Box–Behnken Design

We examined the impact of 3D-printing parameters, such as the deposition pattern, deposition speed, and layer height, on the tribological performance measured through the coefficient of friction and cumulative linear wear. Optimizing these factors can significantly influence material wear and friction, which is critical for ensuring durability and functionality in practical applications like a cylindrical gear assembly for a vertical-articulated robot. The purpose of the study was to investigate these relationships by employing the Box–Behnken design (BBD) method to systematically analyze the effects of these parameters, while also using scanning electron microscopy (SEM) for detailed microstructural characterization. The findings aim to provide insights that can guide the development of more efficient and wear-resistant 3D-printed materials. The strong impact of layer height on CLW was noted, showing that lower layer heights can either improve or worsen wear depending on the combination of speed and pattern, with layer height playing a dominant role in determining wear performance. Lower speeds and specific patterns, particularly lines and concentric patterns, tend to result in higher COF values. The validation test results, with a COF of 0.2215 and CLW of 29.2075, closely align with the predicted values of 0.2064 and 27.3, showing small percentage errors of 7.3% for COF and 6.5% for CLW.