Composite Laminate Impact Damage Assessment by High Resolution 3d X-ray Tomography and Laminography

Improvements to toughening mechanisms in composite materials have hitherto relied on visual inspection techniques that can be rather limited, especially since the inherent damage behaviour is three-dimensional (3D) requiring high resolution to capture micro-cracks and similar damage. To achieve a better understanding of impact damage behaviour, synchrotron radiation computed laminography (SRCL) and computed tomography (SRCT) techniques were used to capture 3D damage mechanisms with voxel sizes of 0.7μm and 1.4μm respectively. Comparisons between impacted toughened and non-toughened carbon fibre reinforced polymer (CFRP) systems were made in which toughening particles were introduced into the matrix of the toughened material. This study has found that at the macro scale, the overall 3D damage pattern in toughened and non-toughened specimens are very similar, however when studied at the micro level, it is clear that significant differences in damage between the two systems exist.