Low Cycle Fatigue Behavior of AA5086-H116: Experimental and Numerical Modeling

In this study, Low cycle fatigue (LCF) behavior of 5086-H116 aluminum alloy material was investigated. Fully turned strain-controlled LCF tests were done at various strain amplitudes (0.50–0.90%) at a constant strain rate of 10–3/sec. Tests were conducted until complete failure, i.e., separating specimens into two halves. The material revealed hardening behavior throughout the considered strain amplitude range with Masing characteristics. The strain energy density (SED), a key parameter representing the material’s response under cyclic loading, remained constant throughout the life for all tested strain amplitudes except that for 0.90%. The fracture surfaces of the broken samples were investigated via FE-SEM to understand the underlying damage mechanism of the material. Most of the fracture surfaces were completely mated; however, a few key characteristic features of fatigue damage could be located. The cyclic stress–strain loops were modeled and simulated using “Chaboche kinematic hardening and Armstrong-Frederick isotropic model”. The percentage error between experimental stress–strain data points and modeled data points was calculated at each loading and unloading cycle, which fitted well with the experimental results and can potentially be used for further studies.