SUMMARY
Prediction of damage due to fretting is complex due to the number of influential factors and the competitive interaction between wear and fatigue. The majority of current fretting damage modeling approaches are limited to narrow ranges of conditions where little competition between damage mechanisms occurs. Recent models which account for damage interaction are largely phenomenological in nature and are still limited to a narrow range of applicability. A method to characterize and model fretting damage is proposed to address the shortcomings of the current methods available by extending the range of conditions captured and enhancing the physical basis of the damage model. The proposed method utilizes experiments performed over a range of material combinations, normal forces, displacement amplitudes, atmospheres, and temperatures, with subsequent damage characterization to determine the level of wear and fatigue damage incurred for each condition tested. A finite element model of the experiment is created to determine the cyclic stress-strain behavior and local frictional energy dissipation for each condition. A fretting damage model will be developed which accounts for the influence of various physical processes to describe the level of wear and fatigue damage. In this model, wear will be predicted as a function of frictional energy dissipation, oxidation behavior, and mechanical properties, and the fatigue damage will be predicted as a function of cyclic stress-strain behavior and changes in mechanical properties as a function of temperature.