Crack Propagation in Aluminum Sheets Reinforced With Boron-Epoxy

The literature has shown that crack propagation in cracked metal sheets can be significantly reduced by bonding an uncracked reinforcement to the metal sheet. However, cyclic debonding typically occurs over a localized area near the crack. Herein, an analysis was developed to predict both the crack growth and debond growth in a reinforced system. The analysis was based on the use of complex variable Green\u27s functions for cracked, isotropic sheets and uncracked, orthotropic sheets to calculate inplane and interlaminar stresses, stress intensities and strain-energy-release rates. An iterative solution was developed that used the stress intensities and strain-energy-release rates to predict crack and debond growths, respectively, on a cycle-by-cycle basis. The analysis was verified with experiments