Alignment of discontinuous recycled carbon fibre

Fibre recycled from end-of-life composites is generally discontinuous and randomly orientated. An intermediate conversion process is required to improve its physical form to make it more readily applicable for use in the composites industry. Non-woven mat manufactured from conventional papermaking processes is one of the direct usages for the recycled fibre. However, due to the 2-D random fibre structure, practical fibre volume content is limited to less than 20% at 10bar pressure. Higher volume content can be obtained with greater moulding pressure but this will result in excessive damage to the fibre length, reducing the fibre reinforcement efficiency. In this paper, a novel alignment process is devised for converting discontinuous random recycled carbon fibre into mat with a highly aligned orientation distribution. This allows composite with higher fibre volume content to be achieved at much lower moulding pressure. A further benefit is that degradation of fibre length is then kept to a minimum. Compression test on dry mats have been performed to determine the change in fibre volume content with the applied pressure. The benefit of having the aligned structure on length preservation will be quantified via an image analysis method. The process also capable of producing aligned mat with high areal density and this help improving production efficiency by reducing number of plies required for part manufacture. Effect of higher area density on alignment quality will be reported.