| Abstract Scope |
Achieving reproducible microstructures and consistent material properties remains a central challenge for qualifying and standardizing metal additive manufacturing (AM) processes. Variations in thermal history from scan strategy, process parameters, and machine-specific effects cause significant variability, even under identical build conditions. We present a validated, physics-based modelling framework linking AM process parameters to thermal history and microstructure evolution to identify metrics for reproducibility and qualification. Using laser powder bed fusion as a representative case, coupled heat transfer simulations and microstructural characterization are employed to quantify temperature gradients, solidification rates, and melt pool dynamics across common scan strategies. These thermal metrics are correlated with grain morphology and crystallographic orientation to distinguish robust processing regimes from those sensitive to parameter perturbations. Results demonstrate limitations of relying on nominal energy density alone and illustrate how thermally informed metrics can support process qualification, parameter screening, reproducibility-focused standards, and digital twin–enabled AM qualification frameworks. |