Feasibility analysis of inter-laminar toughening for improving delamination resistance

This letter discusses the effect of bonding energy on the delamination resistance of laminate composites using a ductile interleaf. The mechanism and methods for interleaf toughening are reviewed and the improvement in delamination resistance discussed. The bonding energy between the ductile interleaf polymer and the fibers as well as between the ductile interleaf polymer and the brittle matrix polymer is shown to be a limiting factor in the interleaf toughening of epoxy based laminates. A dual bonding approach, that is, melt bonding and diffusion bonding, is evaluated as a means to increase the bonding energy between the interleaf and laminate components.