Recent toughening strategies in carbon fiber reinforced composites

Abstract The outstanding specific mechanical properties of carbon fiber reinforced laminates are often counteracted by the poor interlaminar fracture toughness that makes them prone to global failure induced by delamination onset and propagation. The availability of nanofillers have triggered the development of composites reinforced from the micro down to the nanoscale, the so called hierarchical composites. These composites mimic biological materials and promise high mechanical performance with added functionalities. This chapter reviews the recent advances in the exploitation of the multiscale approach to increase interlaminar toughness of advanced carbon fiber reinforced laminates. The techniques for nano-reinforcement integration in conventional composites, from in-situ growth and/or deposition on fibers, dispersion in the matrix, and interleaving of self-standing assemblies are discussed, with a view to emphasizing opportunities, limits and challenges with regard to Mode I and II interlaminar fracture toughness and low velocity impact loading.