Influence of part orientation and spatial placement on the dimensional and surface quality of SLS-printed PA12 components

Abstract Additive manufacturing technologies, particularly Selective Laser Sintering (SLS), are gaining industrial relevance due to their ability to produce complex geometries with high mechanical performance. However, ensuring dimensional accuracy and surface quality remains challenging due to factors such as powder particle size, laser power settings, and the thermal conditions inside the build chamber. Advanced quality control methods, including X-ray computed tomography, enable non-destructive evaluation of internal and external features, offering deeper insights into these issues. This study investigates the effects of part orientation and spatial location within the build chamber on the geometric accuracy and surface quality of components produced via SLS-fabricated components. Fifty PA12 parts were produced in five orientations and distributed across three spatial zones. Dimensional measurements, shape deviations, positional accuracy, and surface roughness were assessed using X-ray computed tomography and surface profilometry. Results showed that outer diameters were close to nominal, while inner diameters were consistently undersized by approximately 0.1 mm and Z-directional lengths exhibited orientation-dependent deviations. Positional accuracy remained stable across orientations but was significantly influenced by spatial location, with increased deviations near the build platform edges. Surface roughness was primarily governed by orientation. These findings provide novel evidence on the combined effect of orientation and spatial placement, emphasizing their critical role in achieving dimensional and surface quality in SLS manufacturing.