Impact resistance and failure mechanism of 3D printed continuous fiber-reinforced cellular composites

The present research investigated previously unexplored attributes of 3D printed continuous fiberglass reinforced Nylon composites, Drop-weight and pendulum (Charpy and Izod) impact resistance including their failure mechanisms with a view to assessing their suitability for prospective high-performance applications such as aerospace, automobile and building industries. The composites were printed with different cellular structures (triangular, hexagonal, rectangular and solid) and three distinct fiber orientations (0/0/0/0, 0/90/0/90 and 0/45/90/-45). Results of the impact assessment of the developed composites exhibited substantial performance when compared to traditional 3D orthogonal plain-woven composites indicating 3D printing process as a promising composite fabrication technology. The effect of fiber orientation was very dominant towards dictating mechanical properties; cross-lay samples (0/90/0/90) absorbed the highest Drop-weigh impact energy followed by quasi-isotropic (0/45/90/-45) and unidirectional (0/0/0/0) composites, while the highest pendulum impact energy was showed by unidirectional composites, followed by cross-lay and quasi-isotropic samples. Incorporation of cellular structure had some effect on the properties measured and composite weight reduction; however, relative contribution of different structures was confounding associating a lot of factors that warn further research.