Analyse de l'influence de la rigidité des patchs composites sur la résistance en fatigue des plaques réparées en alliage d'aluminium 6061-T6

Abstract

The durability of materials subjected to repeated cyclic loading is a major challenge, particularly in industrial sectors. Composite patch repairs are used to extend their service life, but their effectiveness depends on factors such as patch rigidity, overload ratio, and adhesive properties. This study explored the influence of repair patch rigidity, cyclic overload, and adhesive types on the fatigue life of the 6061-T6 aluminum alloy. Simulations were conducted with patches of varying rigidity (80%, 100%, 120%, 140%), overload ratios ranging from 1.5 to 3.5, and three different adhesive types (Graphite/Epoxy, Boron/Epoxy, Glare). The main objective was to measure the impact of these factors on crack propagation rate and the lifespan of the repaired material. The results show that a patch with 140% rigidity (relative to the substrate) delays cracking the most, increasing the lifespan by 40%. A moderate overload ratio (t=2.5) slows crack propagation by 25%, while excessive overload (t=3.5) prematurely damages the repair. Finally, the Graphite/Epoxy adhesive stands out, improving durability by 30-50% compared to other tested adhesives due to its resistance to delamination. These insights guide the development of optimized repair strategies for demanding industrial environments.