Nominal Versus Local Shot-Peening Effects on Fatigue Lifetime in Ti-6Al-2Sn-4Zr-6Mo at Elevated Temperature (Preprint)

Abstract

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Understanding Materials Uncertainty for Prognosis of Advanced Turbine Engine Materials

“…Figure 1 provides a schematic illustration of the dual-fatigue behavior. 9 The above understanding when applied to fatigue design of materials suggests that any compositional, processing, or microstructural modification needs to be focused at the lower-lifetime limit and the associated controlling microstructural configurations, which may not be accurately determined by purely statistical or meanfatigue based approaches. The proposed method, however, enables such a material development process by providing a mechanistic basis for the limiting fatigue behavior.…”