Enhancement of cumulative corrosion-fatigue interaction lives of 6061-t6 aluminum alloy using ultrasonic impact peening process

Abstract EN

The fatigue behavior of 6061-T6 aluminum alloy under constant and variable amplitude loading was investigated in air for as-received and pre-corroded specimens in 3.5% NaCl corrosive solution for 77 days.

The experimental results presented that the tests of fatigue life on pre-corroded samples with and without ultrasonic peening revealed a significant reduction in life related with the presence of corrosion defects before cyclic loading.

In state of unpeened specimens the constant S-N fatigue strength curve was decreased by 4.5% due to immersed the specimens in corrosive 3.5% NaCl solution for 77 days, while in state of ultrasonically peened specimens for 10 sec.

per line and 2.5 joul energy the reduction of S-N curve decreased to 2.2% due to the beneficial effect of this treatment for increasing the corrosion-fatigue life.

The improvement of fatigue life and corrosion-fatigue life of specimens when applying of ultrasonic peening was 8.69% for dry fatigue life and 2.3% for corrosion-fatigue interaction.

The results of cumulative corrosion-fatigue tests indicated that the life of corroded specimens under the effect of ultrasonic peening treatment improved to approximately (3% ـــ 2.25% ) for low-high and high-low The fatigue behavior of 6061-T6 aluminum alloy under constant and variable amplitude loading was investigated in air for as-received and pre-corroded specimens in 3.5% NaCl corrosive solution for 77 days.

The experimental results presented that the tests of fatigue life on pre-corroded samples with and without ultrasonic peening revealed a significant reduction in life related with the presence of corrosion defects before cyclic loading.

In state of unpeened specimens the constant S-N fatigue strength curve was decreased by 4.5% due to immersed the specimens in corrosive 3.5% NaCl solution for 77 days, while in state of ultrasonically peened specimens for 10 sec.

per line and 2.5 joul energy the reduction of S-N curve decreased to 2.2% due to the beneficial effect of this treatment for increasing the corrosion-fatigue life.

The improvement of fatigue life and corrosion-fatigue life of specimens when applying of ultrasonic peening was 8.69% for dry fatigue life and 2.3% for corrosion-fatigue interaction.

The results of cumulative corrosion-fatigue tests indicated that the life of corroded specimens under the effect of ultrasonic peening treatment improved to approximately (3% ـــ 2.25% ) for low-high and high-low sequences.