Experimental investigation on composite patch repair for cracked aluminum structures

This research investigates the effectiveness of fiberglass composite patches in restoring the tensile strength of cracked aluminum structures. Initially, drilling holes to simulate damage significantly weakened the mechanical properties of the aluminum. However, the application of fiberglass fabric or mat laminates over these damaged regions proved to be an efficient method to counterbalance the strength reduction. Notably, the study revealed that 4-ply fabric patches performed better than mat laminates, especially for larger crack sizes. Different failure modes were identified: undamaged sam-ples exhibited necking, pre-cracked samples showed crack propagation, while repaired samples experi-enced adhesive detachment or laminate failure. The results indicate that composite patching presents a promising solution for repairing cracked aluminum structures. Future research should concentrate on exploring alternative patch materials, optimizing patch design, and assessing long-term durability un-der various environmental and load conditions. This study provides a foundation for advancing more effective techniques for repairing metal structures with cracks.