Additive manufacturing (AM), particularly Laser Powder Bed Fusion (L-PBF), holds the potential for producing high-quality parts with intricate details. However, optimizing process parameters for arbitrary alloy chemistries to ensure printability remains challenging. This study evaluates machine learning (ML) models to predict a material’s amenability to L-PBF via the printability index, focusing on High Entropy Alloy (HEA) spaces. The printability index of a material is defined as the percentage of the defect-free L-PBF processing window. Our study revealed that CatBoost Regressors and Random Forest Regressors excel in predictive accuracy, consistently yielding predictions with competitive error metrics such as the mean absolute error (MAE), mean squared error (MSE), root mean squared error (RMSE), and . In addition, competitive rank-order coefficients such as Spearman and Kendall-tau demonstrated that these models are not overfitting. Feature importance analysis using Shapley Additive Explanations (SHAP) highlighted key material properties influencing printability, such as kinetic viscosity, average Pauling electronegativity, and electric conductivity. While both models performed comparably in predictive accuracy, the Random Forest Regressor demonstrated superior computational efficiency, particularly with large datasets. Robustness tests confirmed its reliability across different test sizes. This research underscores the importance of considering factors like computational efficiency, interpretability, and robustness to noise when selecting ML models for L-PBF material printability prediction. Leveraging Integrated Computational Materials Engineering (ICME) methodologies and ML models can significantly optimize process parameters and material properties, paving the way for innovative solutions in L-PBF. This approach accelerates the assessment of new materials and optimizes existing ones for L-PBF processes, contributing significantly to the field of AM.
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A review of machine learning techniques for process and performance optimization in laser beam powder bed fusion additive manufacturing
Laser beam powder bed fusion (LB-PBF) is a widely-used metal additive manufacturing process due to its high potential for fabrication flexibility and quality. Its process and performance optimization are key to improving product quality and promote further adoption of LB-PBF. In this article, the state-of-the-art machine learning (ML) applications for process and performance optimization in LB-PBF are reviewed. In these applications, ML is used to model the process-structure–property relationships in a data-driven way and optimize process parameters for high-quality fabrication. We review these applications in terms of their modeled relationships by ML (e.g., process—structure, process—property, or structure—property) and categorize the ML algorithms into interpretable ML, conventional ML, and deep ML according to interpretability and accuracy. This way may be particularly useful for practitioners as a comprehensive reference for selecting the ML algorithms according to the particular needs. It is observed that of the three types of ML above, conventional ML has been applied in process and performance optimization the most due to its balanced performance in terms of model accuracy and interpretability. To explore the power of ML in discovering new knowledge and insights, interpretation with additional steps is often needed for complex models arising from conventional ML and deep ML, such as model-agnostic methods or sensitivity analysis. In the future, enhancing the interpretability of ML, standardizing a systemic procedure for ML, and developing a collaborative platform to share data and findings will be critical to promote the integration of ML in LB-PBF applications on a large scale.
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- Award ID(s):
- 2134689
- PAR ID:
- 10357045
- Date Published:
- Journal Name:
- Journal of Intelligent Manufacturing
- ISSN:
- 0956-5515
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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