Impact Behavior of Cracked Plate Repaired with Composite and FML Patches

Abstract:

In this paper, the impact behavior of repaired cracked plates was investigated experimentally. single edge cracked aluminum plate having crack length to width ratios of 0.1, 0.3 and 0.5 was repaired with four different patch configurations namely: 3 layer GRP, 5 layer GRP patch, 2/1 FML patch and 3/2 FML patches tested in Charpy impact and the energy absorbed by specimens were compared together and compared with the unrepaired cracked plate. FML patches were made of thin layers of glass/epoxy composites of 0.2 mm thickness with phosphor bronze sheets of 0.2 mm thickness. The patching was single side. The composite and FML patching was more effective in repairing the specimens with greater crack length. Placing 3 GRP and 5 GRP patches increased the absorbed energy by only 3 to 4 joules respectively as compared to unrepaired plate. The use of 2/1 and 3/2 FML patches could increase the absorbed energy two to four times depend on crack length.