An investigation of fretting fatigue in a circular arc dovetail assembly

• A sub-scaled circular arc dovetail specimen was designed.
• A dovetail type fretting fatigue experimental method was developed.
• Numerical simulation based on the test configuration was carried out.
• A new approach to predict fretting fatigue was proposed.

The fretting fatigue of a fan blade–disk attachment in aircraft gas turbine engines was investigated, in which a sub-scaled specimen with one circular arc dovetail root at each end and its fixture were designed and tested under cyclic loading, and the stress distribution in the contact zone and its variation during loading were determined by use of the finite element method. Based on the critical plane method, an approach taking the cyclic strain range and the stress gradient into consideration was developed to predict the fatigue life of specimens, which is verified by the experiments and can be applied to real structures.