Fatigue life prediction of aluminum alloy materials based on surface damage and internal defects

The effects of internal defects and surface damage on fatigue life of periodically damaged specimens are analyzed by means of microscopic computed tomography and microscopic observation. A three-dimensional reconstruction model based on surface damage and internal defects was established, which was confirmed by the experimental data of fatigue damage accumulation during the stages of damage, and a statistical regression model was established by using surface roughness and stress concentration coefficient of the specimens to predict fatigue life.