Quantitative comparison of fretting and plain fatigue: An energy dissipation perspective

This study examines the temperature behavior and energy dissipation per cycle of aluminum 2024-T351 specimens under plain fatigue (PF) and fretting fatigue (FF) loading conditions. The energy dissipation per cycle is accurately determined using an infrared (IR) camera to monitor the temperature at the hottest point. In PF tests, the temperature initially rises sharply, stabilizes after a limited number of cycles, and then increases significantly upon reaching failure. The average accumulated energy dissipation ( E C ) in plain fatigue has been calculated 63.03 MJ/m 3 . In FF tests, a partial-slip regime is established, and similar temperature behavior is observed compared to PF tests. The cumulative energy dissipation under FF conditions remains consistent at about 252.95 MJ/m 3 , while the energy dissipation per cycle increases with increasing loading amplitude. To equivalize PF and FF behaviors, the energy dissipation per cycle ( d in parameter) is used to establish equivalence across different maximum amplitudes. Given the shorter duration of FF tests compared to PF tests in the same axial cyclic loading, utilizing the d in parameter facilitates efficient evaluation and equalization of fatigue behavior between these loading conditions. On the other hand, due to more access to plain fatigue data, using the equivalence relationship can obtain the strength of fretting fatigue.