Damage tolerant Thin-Ply Carbon Fiber Reinforced Composites with Graphene enhanced Matrix

• Applicant: Professor Dr.-Ing. Bodo Fiedler
• Subject Area: Polymeric and Biogenic Materials and Derived Composites ; Mechanical Properties of Metallic Materials and their Microstructural Origins
• Term: from 2015 to 2019
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 283641236

The objective is to optimise the mechanical properties of fibre reinforced polymers (FRP) with a thin-ply laminate structure and a matrix modification with nanoparticles particularly with regard to the damage tolerance against impacts. The resistance against early material damage at free edges is of great importance in many components. An optimisation of this property can be achieved by reducing the single ply thickness of the laminate. With this technology, called thin-ply, the amount of damage, such as microcracking can be significantly reduced at constant total thickness of the composite laminate. However, the smaller amount of damage has negative influence of the mechanical properties of open-hole specimen and with regard to the resistance against impact damage, because of the lower fracture toughness. Thus, the ultimate static strength of thin-ply laminates is lower in comparison to traditional laminates of the same thickness and they show a brittle type of failure. Since the defect development at impact damage is mainly influenced by matrix dominated mechanical properties, it is to be investigated, whether these disadvantages of the thin-ply laminates might be compensated by a polymer modification increasing the fracture toughness with an insertion of nanoparticles. A matrix modification with graphene nanoparticles is here a promising approach that is already applied extensively for optimising traditional FRP. Fibre reinforced polymers with a thin-ply laminate structure and a matrix modification with graphene nanoparticles are to be produced and the failure mechanisms, the influence of ply thickness and layer orientation as well as graphene nanoparticles is to be investigated in order tap the full potential of these promising new materials.

• DFG Programme: Research Grants