The Mechanism and Quantitative Evaluation of Slip Damage of Bolted Joint With Spigot

Bolted joints with spigot are widely-used in the structural design of aero-engines. There will be relative motion at the spigot interface during operating without properly design, which results in the loss of stiffness of bolted joints. In this paper, a slip damage model of the bolted joint is established by analyzing the slip behavior of spigot interface. The influence of structural and loading parameters on slip damage have been studied, and an evaluation method is proposed to quantitatively describe the slip damage of bolted joint with spigot using residual deformation. The results show that the slip damage and the loss of stiffness appear during loading and there will be residual deformation in the bolted joint after unloading because of the friction at the spigot interface. The interference of the spigot and the coefficient of friction have a significant effect to improve the slip damage. In addition, the residual deformation can be used to quantitatively evaluate the slip damage.