Abstract
Crack closure is held to be responsible for very low fatigue crack growth rates in many alloys such as Al-Li 2090 T8E41, and early crack face contact during unloading or prolonged contact during loading seems to reduce the driving 'force' for crack extension. High resolution x-ray computed tomography (i.e., microtomography) allows one to image the entire volumes of samples and to quantify opening as a function of applied load over the entire crack surface. Crack closure results are reported for a fatigue crack grown under load ratio R=0.1 in a compact tension sample of Al-Li 2090 T8E41; the crack was free to choose its path unconstrained by side-grooves which are normally used to suppress crack deflection. The inter-relationship between crack path, crack face contact and applied load level are discussed.
Original language | English (US) |
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Pages (from-to) | 31-35 |
Number of pages | 5 |
Journal | Materials Research Society Symposium - Proceedings |
Volume | 591 |
State | Published - Dec 3 2000 |
Event | The 1999 MRS Fall Meeting - Symposium S 'Nondestructive Methods for Materials Characterization' - Boston, MA, USA Duration: Nov 29 1999 → Nov 30 1999 |
ASJC Scopus subject areas
- General Materials Science
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering