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Engineering Science in
            Additive Manufacturing                                                       ML in additive manufacturing



            challenges related to quality control, material performance,   neural networks, function as “black boxes,” making it
            process repeatability, and scalability. Machine learning   difficult to interpret their decisions. Lack of explainability
            (ML) technology, which has undergone a remarkable   hinders adoption in the industry where understanding the
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            transformation over the past two decades, has shown   rationale behind predictions is critical.  AM process is very
            great potential to address many of these challenges   dynamic requiring potential ML applications to adapt in
            through intelligent and data-driven approaches. Driven   real time, which is challenging for many static complex ML
            by exponential growth in computational capabilities,   models. With improved data quality, efficient and domain-
            unprecedented  access to vast  datasets,  and cutting-edge   constrained ML approaches can be more effective in AM.
            algorithmic innovations, ML models potentially excel   Thus, data quality, quantity, and ML model complexity are
            in analyzing complex datasets, making them suitable   related matters that deserve more research efforts.
            in AM environments where large amounts of factors/   This perspective paper explores the fundamental ML
            features are interconnected or coupled. For example, ML   themes of data and models in the context of academic
            models can predict mechanical properties and optimize   research and industrial adaptation. It highlights key data-
            process parameters, such as laser power, print speed, and   related challenges, including data scarcity, poor data quality,
            layer thickness, to achieve consistent part quality.  They   and high dimensionality, along with ongoing research
                                                    6,7
            can also enhance defect detection by analyzing  in  situ   efforts to address these issues. The paper provides insights
            monitoring data, such as thermal images or acoustic   into the development and evolution of ML techniques
            signals, to identify anomalies during the printing process   over the past decade, emphasizing the increasing model
            in real time.  Moreover, ML has the potential to accelerate   complexity and the emerging learning trends designed to
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            the design process in AM. Generative design approaches   overcome current limitations. Finally, the paper outlines
            enabled by ML can support structure/shape/topology   and proposes key research directions that could accelerate
            optimization to  balance  strength,  weight,  and material   the adoption of ML within the AM industry.
            usage.  These designs often surpass traditional engineering
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            approaches, unlocking new possibilities in industries such   2. Status of ML in AM
            as aerospace, healthcare, and automotive. In addition, ML   The status quo of ML applications in the AM field can
            enables material discovery and development by identifying   be summarized through existing reviews and surveys.
            optimal material compositions and predicting their   Figure 1 categorizes the scope of these reviews into five
            behavior under various conditions, reducing the need for
            extensive physical experimentation.                major  types: Core  ML  themes,  AM process  chain,  AM
                                                               applications, AM software (SW), and AM hardware (HW).
              In the past decade, research in applying ML in AM   Literature reviews concerning core ML themes focus on
            has undergone exponential growth. A  large number of   elements of ML pipelines including input data,  learning
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            publications have come out reporting investigations on   algorithms, 13,14  learning techniques,  and advanced
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            individual  ML  models  for  specific  prediction  targets  in   learning approaches.  AM process chain (design,
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            AM.  However, the challenges posed by data quantity and   process,  and post-process phases ) has been the focus of
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            quality issues were rarely discussed or investigated. Data   ML applications aimed at addressing challenges to product
            quality and quantity are one of the most important factors   design, process repeatability, and manufacturing quality.
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            that determine the performance, reliability, and scalability   As a result, several existing reviews have summarized these
            of ML-driven solutions. Issues such as noisy and incomplete   ML applications in standardized processing technologies
            data, data diversity, data standardization, and data labeling   (e.g., material extrusion [MEX], 19,20  laser powder bed
            are some of the pressing obstacles to overcome.    fusion [LPBF],  directed energy deposition [DED] ). As
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              As the new ML models become more capable, their   technology matures, AM applications are expanding in
            complexity  also  increases  significantly.  Complex  ML   different domains as evidenced by some of the reviews on
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            models,  especially  deep  learning  (DL)  architectures,   manufacturing,   construction,  and health,  to highlight
            are prone to overfitting when trained on limited or   the most significant fields. ML has also advanced AM SW
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            biased datasets. Moreover, a lack of process information,   solutions through progress in monitoring,  control,  and
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            engineering guidance, and domain awareness during the   enhanced digitization.  Research on AM HW elements
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            training can further degrade the performance leading to   (systems  and sensors ) to support the integration of ML
            models with limited generalization and scalability. Training   with AM through systems integration, and sensor fusion
            certain large ML models requires high computational   represents another theme of these reviews.
            resources which is difficult for the AM industry to have   According to the Scopus database, more than 130 review
            access to. Many advanced ML models, such as deep   articles (with search keys: “Additive manufacturing” OR “3d
            Volume 1 Issue 1 (2025)                         2                          doi: 10.36922/ESAM025040004
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