The effects of lamellar orientation and bridging ligaments on the fracture and fatigue of fully lamellar Ti-48Al-2Cr-2Nb
- Univ. of California, Santa Barbara, CA (United States). Materials Dept.
- Harvard Univ., Cambridge, MA (United States). Division of Applied Sciences
The fracture behavior of a fully lamellar Ti-48Al-2Cr-2Nb alloy has been studied under both monotonic and cyclic loading conditions. Crack tip deformations and crack bridging were studied in an attempt to quantify their effects on fracture and fatigue. Crack tip surface strains were determined from in-situ fracture experiments and were used to determine crack tip stress intensities, K{sub tip}, as well as the bridging ligament contribution to fracture toughness, K{sub b}. Both K{sub tip} in monotonic loading and the threshold {Delta}K in fatigue had a strong dependence on lamellar orientation, with K values obtained for cracks parallel to lamellar interfaces {approx} 60% of those for perpendicular cracks. The presence of bridging ligaments increased crack growth resistance during monotonic loading and reduced crack propagation rates during cyclic loading.
- OSTI ID:
- 225161
- Report Number(s):
- CONF-950201--; ISBN 0-87339-304-X
- Country of Publication:
- United States
- Language:
- English
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