Prediction of the tensile stiffness of weft knitted fabric composites based on X-ray tomography images

Knowledge on the micro-structure of composites is important to investigate their mechanical properties such as the tensile stiffness. X-ray computer assisted tomography, often called X-ray CT scan, has been used here to characterise the micro-structure of rib weft knitted fabrics. This tomography technique provides three-dimensional images of rib weft knitted fabrics. The orientation of yarn segments is represented using second order (aij) and fourth order (aijkl) tensors. Micro-mechanical models with respect to the yarn orientation were used to predict the stiffness properties of rib and milano knitted fabric composites.