Study on the Mechanical Property Degradation Laws of 6061-T6 Aluminum Alloy Under the Synergistic Effect of Corrosion and Cyclic Loading

To investigate the mechanical property degradation laws of 6061-T6 aluminum alloy under the synergistic effect of coastal corrosive environments and cyclic loading, the effects of various corrosion durations (0 h, 600 h, 900 h, and 1200 h) on the static performance, hysteretic characteristics, and energy dissipation capacity of the material were studied through indoor accelerated salt spray corrosion tests, monotonic tensile tests, and multi-regime cyclic loading tests. The results indicate that after 1200 h of corrosion, the yield strength and ultimate strength decreased by an average of 2.28% and 5.16%, respectively, with the peak stress point shifting significantly forward. Corrosion significantly inhibits the cyclic hardening effect and accelerates the loss of ductility, with the ductility loss of 1200 h specimens reaching up to 44.0%. Strain is the key factor in activating the energy dissipation potential of the material; when the loading amplitude exceeds 4%, the energy dissipation coefficient stabilizes between 3.0 and 3.3. However, the combination of corrosion and random loading exacerbates the decay of energy dissipation capacity. This study aims to provide a theoretical foundation for the performance assessment and safety assurance of aluminum alloy structures in coastal engineering.