Application of synchrotron radiation micro-CT to local morphological and numerical characterization of short fibre reinforced polymer composites

The behavior of materials with a complex structure strongly depends on the spatial arrangement of their components. In mechanical parts of short glass fibre reinforced polymer (SFRP) obtained by injection moulding, processing conditions produce complex orientation patterns that in\ub0uence the mechanical properties of the component. For example, different fatigue (i.e. failure caused by cyclically repeated loads) behaviors can be observed when short fibre rein- forced polyamide notched specimens of same geometry are injection moulded through gates whose position is varied. This effect appears to be due to the different fibre orientation patterns obtained and it can be interpreted in terms of different local material properties related to fibre orientation and distribution. Traditional, destructive, approaches to fibre pattern identification are affected by severe limitations. Recently, a novel technique based on micro- tomography 3D reconstruction of the fibre structure has been introduced for quantification of fibre pattern