Effect of frequency on the fatigue performance of bolted joints under axial excitation

In a vibration environment, bolted joints may loosen or even fatigue fracture. In this study, fatigue tests of bolted joints were carried out under axial excitation. The effect of loading frequency on fatigue performance was studied. Additionally, the wear mechanisms of bolted joint were revealed. Results show that the wear mechanisms are fatigue wear, oxidation wear and abrasive wear on threads. The fracture morphology presents the characteristics of multi-fatigue cracks and dimples. With the increase of loading frequency, the damage of threads becomes slight, and the self-loosening degree of bolted joint decreases. Moreover, the fatigue life of bolted joint increases because of the decreasing stress amplitude on the section of screw. Numerical simulation was further performed by ABAQUS. The FE results are in agreement with the experimental observations.