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International Journal of AI for
            Materials and Design                                                   AI applications in composite materials



            demonstrated high precision and reliability, with errors   fabric, including localized variations. Alternatively, PINNs
            in the order of 10 . Compared to conventional numerical   can be combined with numerical solvers to enhance
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            methods, such as the finite element method and finite   training when simulating multi-scale problems, such as
            difference approaches, the PINN framework reduced the   the dual-scale permeability of fibrous reinforcements.
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            computation time by over an order of magnitude.    Furthermore, applying active learning to efficiently select
                                                               important training data is expected to provide a more
              To  better  represent  the  response  of  real  fibrous        101
            reinforcements, Lee et al.  incorporated experimental data   effective learning.
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            of the permeability and compressibility relations into the   2.5. Explainable AI (XAI)
            PINN training process to explain the remaining physics
            not expressed in the governing equations, as presented   XAI  is an approach  that aims to  provide clear  and
            in  Figure  6B. Real-time simulations of transverse   interpretable explanations for the results generated by DL
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            permeability measurements were also conducted to extract   models.   Typically, AI functions as a black box, making
            the permeability relation using experimental data of the   predictions without offering sufficient insight into the
            flow rate and injection pressure.                  reasoning behind them. However, as illustrated in Figure 7A,
                                                               the reliability of AI-driven results can be improved by
              These examples demonstrate how PINNs are         utilizing XAI, which provides a transparent explanation of
            transforming composite materials research using more   the decision-making process. This transparency not only
            reliable, faster, and data-efficient methods for prediction,   enhances the reliability of AI systems but also enables users
            design, and  analysis. While  PINNs offer  significant   to better understand and interpret the factors influencing
            potential in the field of composite materials, conventional   the model’s predictions, making AI more accessible in
            PINN models may struggle to fully capture the complex   various applications. When using AI for the analysis and
            multi-physics and multi-scale issues inherent in composite   design of composite materials, simply obtaining the output
            materials. Obtaining a good balance between physics and   values of the results is insufficient. In particular, composite
            data can also be challenging, potentially resulting in slower   materials exhibit nonlinear properties and are sensitive to
            learning rates or difficulties in convergence. In addition, the   numerous factors, requiring careful analysis. While XAI is
            training process is sensitive to network hyperparameters   not a type of DL model, such as DNNs or CNNs, it has
            and can fall into local minima, and research is ongoing to   been widely used with ML models to predict composite
            improve the training performance of PINNs. 96      defects, damage, and mechanical properties, explaining
              To overcome these limitations, it is necessary to   the decision-making process and improving the reliability
            enhance model performance by utilizing hybrid models   of predictive models.
            that combine data-driven neural networks with physics-  Several studies have highlighted the potential of XAI in
            based learning, enabling the simultaneous integration of   this field. 32,104-109  Hong et al.  developed a predictive model
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            physical laws and data-based training. 97,98       for the behavior of a composite pressure vessel and utilized
                                                               XAI to analyze the impact of stacking angle and layer
              A notable advancement in this field is the development
            of a transfer learning-based multi-fidelity PINN framework   thickness on its performance using permutation feature
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            (mfPINN) to mitigate the effects of sparse and noisy   importance  for  each  design  parameter.  Daghigh  et al.
            sensor  data, as well as  the limited accuracy of  idealized   developed an XAI-based ML model for predicting defect
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            governing  equations.   A  low-fidelity  PINN  model  is   characteristics (depth, size, and thickness) in composite
            first trained based on the governing physics. Then, the   materials using infrared thermography (IRT) data and
                                                               evaluated the feature importance of each parameter.
            information learned is transferred to a data-driven DNN,   Yossef et al.  predicted the flexural strength of composite
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            which is trained on a smaller set of high-fidelity data, as   laminates using a decision tree-based gradient boosting
            shown in Figure 6C. The mfPINN framework is used for   algorithm as the ML model. They combined the ML model
            acoustic source localization in anisotropic composites and   with XAI to analyze how the design parameters influence
            is shown to accurately predict the location of defects or   laminate strength and to provide a visual interpretation
            signal sources within composite materials. By integrating   of the relationships between these factors (Figure  7B).
            high-fidelity and low-fidelity data, the mfPINN enhances   Azad and Kim  developed an XAI-based model with
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            localization accuracy while preventing data overfitting   vision transformers to detect damage in CFRP composites,
            and reducing the need for expensive high-resolution data,   as shown in  Figure  7C. Their approach provided visual
            which is often difficult to obtain in practice.
                                                               insights into areas of delamination, enhancing the damage
              In addition, Hanna et al.  used PINNs with CNNs to   detection process. Similarly, Song et al.  applied XAI to
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            predict the 2D permeability tensor field of a glass fiber   textile-reinforced mortar beams to predict the bending
            Volume 2 Issue 3 (2025)                         11                        doi: 10.36922/IJAMD025210016
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