Influence of cyclic action of corrosion and alternate load on fatigue life of 2A12-T4 aluminum alloy

Tests of alternate corrosion and fatigue for 2A12-T4 aluminum alloy were performed in order to reveal the influence of factors related with corrosion environment and load on its fatigue life. The effect of the alternate frequency of corrosion/fatigue and the type of corrosion tests such as alternate immersion, salt spray and salt spray+hot and humidity corrosion on the degradation of 2A12-T4 aluminum alloy was analyzed. The results show that for a designated total time of corrosion, the alternate frequency of corrosion/fatigue has important influence on the fatigue life of the alloy. The fatigue life of the alloy increases gradually with the increasing alternate frequency. The total fatigue life of aluminum alloy for 2, 4 and 6 cycles were 16.9%, 30.7% and 50.3% respectively higher than that for the first cycle. Besides, the type of corrosion tests also has important influence on the fatigue life of the alloy, of which the impact intensity may be ranked in a descending order as follows: salt spray corrosion > alternate immersion corrosion ＞salt spray+ hot and humidity corrosion.