Additive Layer Manufacturing of Biologically Inspired Short Fibre Reinforced Composites

Abstract : This project provided fundamental understanding towards novel additive layer manufacturing approaches for highly-ordered, short-fiber architectures. The fabrication challenge is a critical hurdle to the realization of complex, multi-scale architectures inspired by nature for improving the mechanical and functional properties of engineered materials. The study was advanced on two fronts: (1) development of new hierarchical architecture based on ZnO nanorods grown on glass fibers and coated with tetraethyl orthosilicate (TEOS) to promote self-assembly; and (2) exploitation of ultrasonic manipulation for controlling orientation and distribution of reinforcing short fibers. The ZnO/TEOS nanorods were shown to preserve mechanical properties of the base fibers while also displaying some healing capability for defects. For the ultrasonic manipulation, both micro-scale and nano-scale reinforcements were studied using a new prototype assembly system developed for the project. Enhancement of stiffness and strength properties in aligned directions was observed despite low volume fraction of reinforcement.