Effect of Build Orientation and Part Location on Surface Roughness of PA12 Components Fabricated by Selective Laser Sintering

Selective laser sintering (SLS) enables the fabrication of polymer components with intricate geometries; however, surface roughness remains a concern that affects performance and quality. This study systematically examines the influence of build orientation (X, Y, Z) and part location (inner, middle, outer) on surface roughness of Polyamide 12 (PA12) components. The results show that components built in the Y orientation and placed in the inner chamber exhibited the lowest surface roughness (Sa = 9.88 ± 0.16 µm). In contrast, Z-oriented components at the outer edge showed the highest (Sa = 11.49 ± 0.27 µm), indicating a 10.13% variation. SEM analysis showed smoother morphology and reduced porosity in the inner regions, while DSC confirmed higher crystallinity in samples with improved finish. These findings highlight the role of thermal stability and spatial positioning within the build chamber in controlling surface characteristics, emphasizing the importance of orientation and placement strategies for improving the quality of PA12 components fabricated by SLS.