A smart repair system for polymer matrix composites

The widespread use of polymer composites is still caveated with concerns about the loss in structural performance that can result from impact damage. Such events give rise to delaminations which may not be easily detectable by eye. This paper describes a technique for 'smart' repair of delaminations in polymer composites. This involves the filling of hollow fibres with a resin, which is released into the damaged area when the fibre is fractured. A two-part epoxy resin is used as the repair medium, the two components being diluted with solvent and infiltrated into different plies of a composite based on 'Hollex' S2-glass fibre. Compression strength after impact tests were used as a measure of the effectiveness of the repair technique, and a potential improvement was noted after application of heat and vacuum to the damaged composite. Resin release from the fibres was noted by microscopy. A more comprehensive study is required to verify the improvement in post-impact strength, and the use of larger internal diameter fibres would enhance the amount of resin released. Crown Copyright (C) 2001 Published by Elsevier Science Ltd. All rights reserved.