Visualization and quantification of low-velocity impact damage of three-dimensional braided CFRP composites by micro-computed tomography

In this paper, the low-velocity impact response and damage of three-dimensional five-directional (3D5d) braided carbon/epoxy composites under different energies (30 J, 65 J, 100 J) are studied. Importantly, the damage is segmented from the axial and radial directions of the yarn to visualize and quantify the damage distributions in different regions based on micro-CT. The results show that as compared with the samples under 30 J and 100 J, the samples under 65 J energy perform higher impact properties. Moreover, as the impact energy increases from 30 J to 100 J, the corresponding damage volume increases from 6.886 mm3 to 477.133 mm3. Furthermore, the damage distributions are almost symmetrical in space.