Detailed characterization of voids in multidirectional carbon fiber/epoxy composite laminates using X-ray micro-computed tomography

Abstract

We employ X-ray micro-computed tomography to generate an extensive dataset of voids' characteristics in carbon/epoxy laminates with different stacking sequences. The voids are deliberately induced by modifying the cure cycle. The three-dimensional images with voids are segmented and quantified using an in-house software package, VoxTex. The characteristics of voids, i.e. shape, size parameters, orientation, and spatial location distribution, are obtained. The majority of voids have slightly flattened cross-sections. The voids prefer to localize in the inner plies of the laminate, rather than in the outer ones. Near the laminate mid-thickness, they become more elongated. The stacking sequence affects the size and shape of voids. The planar location of voids is not random and tends to create a pattern, corresponding to the the ply orientations in the laminate. The data is reported in detail, ready to use, for example, as input for modeling studies of similar composites with voids. Response to Reviewers: The response to the reviewer's comments is provided in a separate MS Word file, which is uploaded along with the submission.

A dataset of void characteristics in multidirectional carbon fiber/epoxy composite laminates, obtained using X-ray micro-computed tomography

“…2, the change that occurred to the rest of the histogram, after filtering the false features, is caused by recalculating the “relative” frequencies for the new data.

Fig. 2Frequency distributions of the semi-minor axis and the in-plane orientation of the ellipsoids fitted to the detected voids in the [±45] 2s specimen (left) before and (right) after filtering [1].

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“…Frequency distributions of the semi-minor axis and the in-plane orientation of the ellipsoids fitted to the detected voids in the [±45] 2s specimen (left) before and (right) after filtering [1]. …”

“…2The small difference in the percentile values between the spreadsheets and the reference article [1] is due to the difference in percentile calculation methods between MATLAB and Microsoft Excel .…”

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