Analysis of void morphology in composite laminates using micro-computed tomography

VoxTex software for quantification of micro-CT images provides useful tools for analysis of voids in fibre reinforced composites. These tools are applied in the current work to (1) carbon fibre laminate (-45/0/45/-20/0/20/90/0) so, made with automated dry fibre placement and vacuum assisted resin transfer moulding and to (2) carbon fibre laminates [0/90]ns, made by prepreg technology and cured in autoclave witha regime proliferating void formation. The materials contain very different porosity levels (below 1% for (1) and few percent in (2)). The segmentation and image processing algorithms allow identification of the overall void content and quantification of the void dimensions and their orientation in the form of distribution functions. These distributions are presented and their characteristic features are discussed. A typical peculiarity of segmented micro-CT images is presence of small (few pixels in size) voids, which persist even after the spurious "void pixels" are eliminated. Whether these micro-void-features represent real microscopic voids in the material is discussed based on the comparison with SEM images.