OUT-OF-AUTOCLAVE REPAIR OF COMPOSITE LAMINATES BY USING SHAPE MEMORY POLYMER FOAMS

Composite repairing is an issue because of the size of the parts, the cost of the production equipment and the poor consolidation between the parent part and the repairing patches. In this study an out-of-autoclave procedure is proposed where the agglomeration pressure is provided by shape memory foams. These foams can be shaped in the desired form by means of a thermos-mechanical cycle, and provide additional pressure if constrained during recovery. Shape recovery is achieved by using the same thermal cycle which is necessary for the cure of the patches. In this study, thermoplastic shape memory foams have been characterized to evaluate the agglomeration pressure they can provide as a function of the compression strain. In order to show the feasibility of their application, the cure of a composite laminate has been performed by using pre-shaped shape memory foams. Results show that a good consolidation is achieved despite of the absence of a vacuum bag.