Laminate fibre structure characterisation of carbon fibre-reinforced polymers by X-ray scatter dark field imaging with a grating interferometer

摘要

X-ray scatter dark field imaging (SDFI) using a Talbot-Lau grating interferometer has recently attracted growing interest for the non-destructive testing and evaluation of light materials. In this work, we developed the method further for the characterisation of the laminate structure of carbon fibre reinforced polymers. In particular, we used the anisotropic properties of the small angle scattering signal to image the fibre bundles running in different directions independently with excellent contrast. The results obtained for four different woven carbon fibre reinforced polymer samples were compared to high resolution X-ray computed tomography results. We found that SDFI allows for the visualisation of the weave pattern structure and analysis of the size of the carbon fibre bundle in three dimensions, even if the individual fibres cannot be separated or the absorption contrast between the carbon fibres and the epoxy matrix is very low.