Military Gas Turbine Engine High-Cycle Fatigue (HCF) Mitigation

The JSF Program requires a probabilistic approach to high cycle fatigue (HCF) foreign object damage (FOD) limit determination. The current Goodman diagram based methods have a capability gap addressing the JSF probabilisitic requirements and are costly and time consuming due to the extensive bench fatigue testing required. Through Phase I and II SBIR contracts VEXTEC demonstrated the ability to use probabilistic microstructural modeling methods requiring significantly less test data and yielding more accurate results on "industry" titanium blades. The analytical tool VEXTEC created needs to be evaluation using existing JSF data, designs,and materials before it can be included in engine OEM designs. The goal of the proposed expansion effort is to demonstrate the application of VEXTEC’s technology on a JSF first stage fan blade to predict fatigue durability under various surface treatment, foreign object damage and repair conditions. The by product of this effort will be the development of a simulation tool that P&W can use to provide a level of tractability to VEXTEC simulation results.