PSI - Issue 37

Andrzej Katunin et al. / Procedia Structural Integrity 37 (2022) 195–202 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

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3.3. Results of processing of X-ray computed tomography scans The acquired XCT scans in a form of sequences of 2D slices were subjected to image segmentation to separate the detected damage from the background, representing a texture of a reinforcing fabric. The image segmentation was based on the custom-developed algorithm, which used an adaptive thresholding (see (Wronkowicz-Katunin et al., 2019b)). Further, the obtained results were binarized and filtered using appropriate filters and morphological operations to remove the measurement noise and scanning artifacts. The example of the processed XCT scan is presented in Fig. 4.

Fig. 4. The exemplary reconstructed map of BVID from an XCT scan.

4. Development of a parametric model of impact damage The analysis of the obtained results revealed numerous differences both in a shape of BVID as well as in a distribution of the delaminated areas across the thickness of the composite structure. The collected results from the NDT experiments as well as from the FE model were used to evaluate the generic shapes and dimensions of BVID for the considered energies of impact loading and impactors’ tips radii. Since the XCT results were considered as the reference data, the shapes of BVID were assumed based on the XCT reconstructions, which were flattened to attribute the detected delaminated areas to interfaces at the particular depths. The exemplary contours of the delaminated areas are presented in Fig. 5.

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Fig. 5. The exemplary contours of delaminated areas of a BVID attributed to the interfaces at particular depths: (a) 3D view, (b) top view.