Evaluation of the Effects of Corrosion on Fatigue Life of Clad Aluminum Alloy 2024-T3-Riveted Lap Joints with Acoustic Emission Monitoring
Corrosion affects the fatigue life of clad aluminum alloy-riveted lap joints, such as those found on an aircraft fuselage structure. Single-, double-, and triple-column-riveted lap joint specimens were fabricated and corroded in a Q-Fog accelerated corrosion chamber for five months using an ASTM G85-A5 prohesion test. Specimens were taken out of the chamber every 4 weeks, and the corrosion products which had been deposited on them were removed by immersion in concentrated nitric acid. For each corroded specimen, the mass loss with corresponding corrosion rate was determined. The specimens were fatigue loaded to failure on an MTS Universal Testing Machine with acoustic emission monitoring. Results indicate that exposure of lap joint specimens to this corrosive environment increased corrosion (mass loss), corrosion rate, and significantly reduced fatigue life. For a prolonged exposure in the corrosive environment, the fatigue life was reduced to zero, which has significant implication for aging aircraft. Acoustic emission monitoring successfully detected fatigue failure. Two failure modes, multisite crack damage and shear of the rivets, were observed.
A. C. Okafor and C. Nnadili, "Evaluation of the Effects of Corrosion on Fatigue Life of Clad Aluminum Alloy 2024-T3-Riveted Lap Joints with Acoustic Emission Monitoring," Journal of Failure Analysis and Prevention, Springer Verlag, Jan 2012.
The definitive version is available at http://dx.doi.org/10.1007/s11668-012-9606-9
Mechanical and Aerospace Engineering
Keywords and Phrases
Corrosion; Fatigue Life; Accelerated Corrosion Testing; Riveted Lap Joints; Acoustic Emission
Article - Journal
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