Measurement of Delamination Fracture Energy Using Stepped Laminates

Delamination is often the mode of failure in laminated composites. Therefore the quantification of delamination fracture energy is of vital importance. In this work, externally stepped graphite/epoxy (T300/934) laminates are tested in flexure, resulting in a series of delaminations at 0/90 interface. The delamination fracture energy is calculated based on the strain energy released and is found to be 535 J/m 2 . This value is in good agreement with the mode II strain energy release rate obtained by other workers.