3D characterisation of local deformation and damage development in tailored fibre placement-manufactured composites under tensile loading

The tensile response of Carbon Fibre Reinforced Polymer (CFRP) composites manufactured through Tailored Fibre Placement (TFP) has been investigated using micro X-ray computed tomography (μXCT) with in-situ mechanical testing combined with digital volume correlation (DVC). Damage mechanisms have been studied in relation to full-field strain measurements through regular interruptions of the tests and post-processing of the reconstructed images of the internal structure of the composite using a new Python-based DVC algorithm. A global DVC strategy has been developed to obtain deformation fields based on the correction of large rigid-body motions from a local DVC approach. Results show quantified strain distributions and their evolution in the complex 3D structure of the textile composite, in particular in resin-rich regions around stitch threads affecting damage development. The developed methodology therefore offers new opportunities for a better understanding of complex damage development in TFP composites as well as validation means for multiscale models aimed at predicting their mechanical response.