Prediction of fatigue life in interference fitted Al-alloy 2024-T3 plates used indouble shear lap joints

In this paper, stress analysis of holed plates was implemented in order to estimate the fatigue life of double shear lap joints involving interference fitted pin. The fatigue life was divided into two phases of crack initiation life and fatigue crack growth life. The fatigue crack initiation and fatigue crack growth life estimations have been numerically investigated and the total estimated fatigue lives have been compared with the available experimental fatigue test results. To obtain the pre-stress and strain distributions created by interference fit, and also the stress and strain distributions under cyclic longitudinal loads, three-dimensional finite element models were employed using ANSYS software. The results obtained from the finite element analysis of interference fit were employed to predict fatigue crack initiation life using Fatemi–Socie multiaxial fatigue criterion. Pre-stress fields resulting from interference fit and also the longitudinal loading effect were introduced to the AFGROW code toobtain the effective stress intensity factor for the estimation of fatigue crack growth life. The results show that there is a good agreement between the numerically predicted total fatigue life and available experimental fatigue test results.

Keywords:

Life prediction , Double shear lap joints , Interference fit , Fatigue crack growth , Multiaxial fatigue criteria