Fractographic observations on Dyneema® composites under ballistic impact

Although there is a considerable interest in lightweight composites for armour, there is a limited understanding as to their detailed energy absorbing processes. In particular, the relative contributions of the critical damage processes and their interactions, are not known. The work reported here presents fractographic observations on laminates which have been exposed to ballistic impact. The sequence of failure modes (and their interaction), such as delamination, ply splitting and fibre kinking, through the laminate during the impact event have been deduced, and the influence of processing conditions and target response on the damage processes have been gleaned. Such knowledge provides a means for optimising the performance of these materials, modelling their behaviour and tailoring of their constituents.