Dwell fatigue, the reduction in fatigue life experienced by titanium alloys due to holds at stresses as low as 60% of yield, has been implicated in several uncontained jet engine failures. Dislocation slip has long been observed to be an intermittent, scale-bridging phenomenon, similar to that seen in earthquakes but at the nanoscale, leading to the speculation that large stress bursts might promote the initial opening of a crack. Here we observe such stress bursts at the scale of individual grains in situ, using high energy X-ray diffraction microscopy in Ti–7Al–O alloys. This shows that the detrimental effect of precipitation of ordered Ti3Al is to increase the magnitude of rare pri〈
Nucleation of in‐service cracks leads to detrimental consequences for structural components of near‐
- NSF-PAR ID:
- 10373697
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Fatigue & Fracture of Engineering Materials & Structures
- Volume:
- 46
- Issue:
- 1
- ISSN:
- 8756-758X
- Page Range / eLocation ID:
- p. 271-294
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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