Damage mechanics method for fatigue life prediction of Pitch-Change-Link

According to the law of thermodynamics, a new damage evolution equation is advanced in the present study to predict the fatigue life of the Pitch-Change-Link component. As its premise, the fatigue life prediction method for smooth specimens under the repeated loading with constant strain amplitude is constructed. In addition, based on the theory of conservative integral, the closed form relation for notched specimens between the maximum stress and fatigue life is derived, by reference to which the material parameters in damage evolution equation are obtained with fatigue experiment data of standard specimens. The damage mechanics-finite element method operates with APDL language code on the ANSYS platform. Finally, the mean fatigue crack initiation life of Pitch-Change-Link is predicted with the newly proposed method, that is damage mechanics-finite element method. What's most important, the calculated results comply with the experimental data.