Fatigue Assessment of 2024-T351 Aluminum Alloy Under Uniaxial Cyclic Loading

In this paper, an experimental and numerical study of the fatigue life of 2024-T351 aluminum alloy has been investigated. For this purpose, mechanical properties of the material are obtained by tensile test. The Manson–Coffin–Basquin equation is used to estimate the fatigue life. The specimen surface is photographed using a microscope camera to examine the specimen deformation. The ratio of white to black pixels on the specimen surface that changes during loading is investigated using the image processing method. Changes in the ratio of white to black pixels indicate that material fatigue is associated with the specimen surface. The experiments are strain-controlled and in 6 different strain amplitudes on the specimens. Then, by obtaining the amplitude range of elastic and plastic strains in the stress–strain hysteresis loop, the coefficients of the Manson–Coffin–Basquin equation are calculated in a stable cycle. Using these coefficients, the Manson–Coffin–Basquin equation is presented to estimate the fatigue life of the material in an amplitude of different strains. A comparison of the results of this equation and the experimental results show a good agreement.