Prediction of fatigue 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 the level of fatigue damage due to fretting was developed in this work 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.
Baseline material properties for thin sheets of AISI 301 stainless steel in the full hard condition were determined as a function of temperature through tensile tests, fatigue tests, and metallography. Fretting experiments were performed for contact between 301 stainless steel and each ANSI A356 aluminum and AISI 52100 steel. Fretting experiments were performed over a range of material combinations, normal forces, displacement amplitudes, atmospheres, and temperatures. Subsequent characterization of the damage due to fretting was performed to determine the level of wear and fatigue damage incurred for each condition tested.
A finite element model of the experiment was created to determine the cyclic stress-strain behavior and local frictional energy dissipation for each condition. Fatigue damage metrics were evaluated to determine the effects of the contact conditions on the driver for fatigue damage. A new model for fatigue damage due to fretting was developed which incorporates the wear behavior to describe the effect of wear on the level of fatigue damage caused by fretting. The level of fatigue damage is influenced using a function of frictional energy dissipation and wear rate to account for differences in wear mechanisms and changes in the severity of wear caused by changes in oxidation behavior and mechanical properties which result from changes in temperature or contacting materials.
| Identifer | oai:union.ndltd.org:GATECH/oai:smartech.gatech.edu:1853/52975 |
| Date | 12 January 2015 |
| Creators | Hirsch, Michael Robert |
| Contributors | Neu, Richard W. |
| Publisher | Georgia Institute of Technology |
| Source Sets | Georgia Tech Electronic Thesis and Dissertation Archive |
| Language | en_US |
| Detected Language | English |
| Type | Dissertation |
| Format | application/pdf |
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