THE EFFECT OF STACKING-SEQUENCE ON IMPACT DAMAGE IN A CARBON-FIBER EPOXY COMPOSITE

The effect of stacking sequence on impact damage in a carbon fibre/toughened epoxy composite was studied. The major form of damage was delamination, which initiated at almost every interface through the panel. During the impact event the force-time response was monitored and the energy absorbed analysed in terms of an initiation and a propagation energy. The energy absorbed in delamination initiation was influenced by the stacking sequence, being increased by placing 45-degrees fibres in the surface plies and by increasing the number of dissimilar interfaces. The residual energy absorbed in delamination propagation was found to increase linearly with increasing total delamination area. The compression-after-impact strength was related to the maximum delamination area.