Comparative Fretting Fatigue Life Evaluation between Critical Plane Based and Deviatoric Strain Amplitude Based Methods Corrected for Surface Wear Damage 05-15-02-0009

Fretting failure mode is commonly observed at the contact interface of mating parts, held together under normal load and subjected to vibratory and/or imbalanced system forces. This article presents the fretting fatigue life estimation of a complete flat-flat contact pair using a relatively new approach, i.e., deviatoric strain amplitude-based (SI) parameter, further combined with Ding’s empirical parameter D _fret2, which considers the effect of resultant frictional work on fretting fatigue life. The results are compared with traditional critical plane-based methods like Smith-Watson-Topper (SWT) and Fatemi-Socie (FS). Observing high load-factor values corresponding to material yielding, non-linear material models are considered to account for possible plastic shakedown/ratcheting phenomenon. Overall good experimental correlation is observed for all three fatigue initiation methods, within a ±3N scatter band. The advantage of deviatoric strain amplitude-based parameter over SWT and FS methods is that it does not require critical plane-based calculations and, hence, is computationally more efficient. The effect of wear on fretting fatigue is considered through two different techniques: progressive wear modeling and fretting-specific parameter. Under progressive wear modeling technique, Archard’s wear model is considered whereas Ding’s D _fret2 parameter is considered under fretting specific parameter. Since Ding’s D _fret2 parameter, considers the correction factor corresponding to actual frictional work, it predicts a better correlation than Archard’s wear model, which considers a single wear coefficient value for different load-stroke combinations.