Influence of Pre-stress Corrosion on Fatigue Life of 2A12-T4 Aluminum Alloy

Pre-stress corrosion experiments of 2A12-T4 aluminum alloy under two kinds of temperature, three kinds of stress level and different immersion times in EXCO solution were conducted, and then fatigue experiment was implemented to calculate the fatigue life. Multi-variance analysis showed that the corrosion temperature, immersion time and stress level were remarkable factors affecting the fatigue life. Corrosion is being aggravated by the three effects working together, and the fatigue life is reduced. A residual fatigue life calculation model, token with corrosion temperature, immersion time and stress level, was established by regression arithmetic based on the test results. Comparing theoretical values and experimental datas, the errors are about 25%. The fracture surface was observed by SEM, the microscopic damage mechanism of temperature, immersion time and stress level were analyzed.