RA-based fretting fatigue life prediction method of Ni-based single crystal superalloys

Fretting fatigue damage can significantly reduce the service life of Ni-based single crystal (NBSX) superalloys turbine blades. In this work, we proposed a fretting fatigue life prediction method by considering cracking, wear and their mutual interaction. Specifically, a parameter, denoted as RA, is developed with combination of Resolved shear stress based damage factor and Accumulated dissipated energy based damage factor, by which the contribution from cracking and wear are described respectively. The proposed method is validated with experimental data in the literature. Finite element analyses are performed to study the distribution of stresses and strains. Results show that the predicted crack initiation site, failure plane and life cycles are consistent with the experimental results.