Micro-CT analysis of the orientation unevenness in randomly chopped strand composites in relation to the strand length

Multi-sample X-ray micro-computed tomography (micro-CT) is used for the statistical analysis of the internal geometry of randomly oriented strands (ROS) composite - ultra-thin chopped carbon fiber tape reinforced thermoplastics (UT-CTT) with different tape lengths. The accuracy of the micro-CT measurements and their quantification for the local fiber orientation is assessed and the statistical significance of the observed trends in the fiber orientation is confirmed. The effect of tape length on structure morphology and orientation concentration is investigated. Increasing the tape length decreases the number of internal structure irregularities (scattered fiber clusters and out-of-plane fiber disturbance for instance) present in UT-CTT.