Prediction of the impact behavior of bio-hybrid composites using finite element method

The use of composite hybridization using both synthetic and natural fibers, is one of the most established way to combine the advantages of each material that forms the composite system in order to obtain a composite with good in-plane and out-of-plane properties. For example, as pointed out in authors previous research works, considering carbon/hemp hybrid composites, it is possible to combine the ductile behavior and the capacity to absorb energy of hemp fibers with the higher strength and stiffness of carbon allowing the development of a hybrid system with enhanced energy absorption capability, reduced production cost and lower environmental impact respect to traditional carbon fibers composites. The aim of this work is to investigate both experimentally and numerically the mechanical behavior at impact of pure carbon, pure hemp and carbon/hemp hybrid composite laminate. Low velocity impact tests at 10 J and 20 J were carried and non-destructive analyses were performed for each impact energy to evaluate the internal damage extent. The same tests were numerically simulated with LS-DYNA software using shell elements and different material cards (i.e. MAT 54/55, MAT 24 depending on typology of fibers) and contact conditions in order to find the best configuration that matches the experimental results.