Physics guided heat source for quantitative prediction of IN718 laser additive manufacturing processes

• Published in: npj computational materials 2024-02, Vol.10 (1), p.37-14, Article 37
• Main Authors: Amin, Abdullah Al, Li, Yangfan, Lu, Ye, Xie, Xiaoyu, Gan, Zhengtao, Mojumder, Satyajit, Wagner, Gregory J., Liu, Wing Kam
• Format: Article
• Language: English
• Subjects: 639/166; 639/301/1034/1037; Additive manufacturing; Aspect ratio; Beds (process engineering); Calibration; Characterization and Evaluation of Materials; Chemistry and Materials Science; Computational fluid dynamics; Computational Intelligence; Computer applications; Cooling rate; Diameters; Experiments; Heat; Lasers; Liquid cooling; Manufacturing; Materials Science; Mathematical and Computational Engineering; Mathematical and Computational Physics; Mathematical Modeling and Industrial Mathematics; Mathematical models; Melt pools; Melting; Parameterization; Parameters; Powder beds; Predictions; Scaling laws; Theoretical; Thermal measurement
• ISSN: 2057-3960; 2057-3960
• DOI: 10.1038/s41524-024-01198-6

Challenge 3 of the 2022 NIST additive manufacturing benchmark (AM Bench) experiments asked modelers to submit predictions for solid cooling rate, liquid cooling rate, time above melt, and melt pool geometry for single and multiple track laser powder bed fusion process using moving lasers. An in-house developed A dditive M anufacturing C omputational F luid D ynamics code (AM-CFD) combined with a cylindrical heat source is implemented to accurately predict these experiments. Heuristic heat source calibration is proposed relating volumetric energy density (ψ) based on experiments available in the literature. The parameters of the heat source of the computational model are initially calibrated based on a Higher Order Proper Generalized Decomposition- (HOPGD) based surrogate model. The prediction using the calibrated heat source agrees quantitatively with NIST measurements for different process conditions (laser spot diameter, laser power, and scan speed). A scaling law based on keyhole formation is also utilized in calibrating the parameters of the cylindrical heat source and predicting the challenge experiments. In addition, an improvement on the heat source model is proposed to relate the Volumetric Energy Density (VED σ ) to the melt pool aspect ratio. The model shows further improvement in the prediction of the experimental measurements for the melt pool, including cases at higher VED σ . Overall, it is concluded that the appropriate selection of laser heat source parameterization scheme along with the heat source model is crucial in the accurate prediction of melt pool geometry and thermal measurements while bypassing the expensive computational simulations that consider increased physics equations.