Refined Critical Plane Methodology for Predicting Fretting Fatigue Crack Initiation Based on Shear Strain Dynamics

The present study posits that variations in maximum shear strain energy are the principal determinants for the onset of fretting fatigue cracks. We propose a refined critical plane methodology, termed the shear stress-strain interaction (SSI) critical plane method, predicated on shear strain, for predicting fretting fatigue crack initiation characteristics. The novelty of this methodology resides in its focus on cyclic shear strain as the genesis of crack initiation. To verify the effectiveness of the SSI critical plane method, finite element analyses using ANSYS were executed on fretting bridge and pad models to quantify the SSI interaction parameters. A comprehensive evaluation against established metrics-maximum shear range, stress-weighted tangential parameters, and fretting parameters was undertaken. The findings, in alignment with extant experimental data, confirm the robustness of the proposed method.