Effect of Printing Direction of 3D-Printed Nylon Under Abrasive Wear Conditions

This study evaluates the effect of printing orientation on the wear resistance of 3D-printed nylon fabricated via Fused Deposition Modeling (FDM). We conducted abrasive wear resistance tests, thermal analysis, and microstructural characterization using scanning electron microscopy before and after wear testing. The results show that alternating printing directions lead to significantly higher wear. Under a normal load of 130 N, this configuration caused the exposure of up to four layers. At the same time, single-orientation prints exhibit lower material loss and better filament cohesion. DSC analysis reveals that all printed samples, regardless of wear exposure, display dual melting temperatures (T_s1 and T_s2) due to distinct crystalline phase formations. Abrasion decreases the secondary melting temperature (T_s2) and increases enthalpy by up to 144% compared to unprinted nylon, highlighting the thermal history on structural properties. These findings emphasize the critical role of printing configurations in optimizing the tribological performance of 3D-printed nylon for industrial applications.