Improving Vertical Dimensional Accuracy in PBF-LB/M Through Artefact-Based Evaluation and Correction

Achieving high dimensional accuracy in the build direction remains a critical challenge in laser-based powder bed fusion of metals (PBF-LB/M), particularly for taller components. This study investigates the application of the standardized Z-artefact defined in ISO/ASTM 52902:2023 to evaluate and correct vertical dimensional deviations in AlSi10Mg parts. Benchmark artefacts were produced without Z-scaling and measured using a structured light 3D scanner. A linear trend of increasing undersizing with build height was observed across two build jobs, indicating a systematic Z-error. Based on the reproducible average deviation, a shrinkage compensation factor of 1.0017 was derived and applied in a third build job using the same processing parameters. This correction reduced the root mean square error (RMSE) from over 100 µm to below 25 µm and improved the achievable ISO tolerance grades from IT 9–11 to IT 5–9. The approach proved effective without requiring changes to process parameters. However, local surface features such as elevated edges and roughness remained dominant sources of deviation and are not captured in step height-based evaluations. Overall, this study demonstrates a practical, standard-compliant method to improve vertical dimensional accuracy in PBF-LB/M, with potential applicability to industrial quality assurance and future extension to more complex geometries.