Micro-CT measurement of fibre misalignment: Application to carbon/epoxy laminates manufactured in autoclave and by vacuum assisted resin transfer moulding

This paper proposes a methodology for measurement of fibre misalignment in composite laminates based on the structure tensor of fibre orientations extracted from X-ray micro-computed tomography (micro-CT) images. The methodology is applied to carbon fibre/epoxy composites manufactured with two technologies: (1) by prepregging and consolidation in an autoclave and (2) by vacuum assisted resin transfer moulding. The results show that the in-plane inter-ply misalignment of fibres in the prepreg laminate and in the infusion-produced laminate is within 2-4° and 1-2°, respectively. The misalignment results allow better understanding of the manufacturing typical fibre orientation precision level for the low pressure (vacuum assisted resin transfer moulding) and high pressure (autoclave) manufacturing.