Abstract
The aim of this research is to understand the influence of notches under thermomechanical fatigue (TMF) in a directionally-solidified (DS) Ni-base superalloy. Experiments were performed utilizing linear out-of-phase (OP) and in-phase (IP) TMF loadings on longitudinally-oriented smooth and cylindrically-notched specimens. Several notch severities were considered with elastic stress concentrations ranging from 1.3 to 3.0. The local response of the notched specimens was determined using the finite element method with a transversely isotropic viscoplastic constitutive model. Comparing the analysis to experiments, the locations observed for crack nucleation in the notch, which are offset from the notch root in DS alloys, are consistent with the maximum von Mises stress. Various local and nonlocal methods are evaluated to understand the life trends under OP TMF. The results show that a nonlocal invariant area-averaging method is the best approach for collapsing the TMF lives of specimens with different notch severities.
Original language | English |
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Pages | 2456-2465 |
Number of pages | 10 |
State | Published - 2013 |
Externally published | Yes |
Event | 13th International Conference on Fracture 2013, ICF 2013 - Beijing, China Duration: Jun 16 2013 → Jun 21 2013 |
Conference
Conference | 13th International Conference on Fracture 2013, ICF 2013 |
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Country/Territory | China |
City | Beijing |
Period | 06/16/13 → 06/21/13 |
Keywords
- Ni-base superalloy
- Notch analysis
- Notched specimens
- Thermomechanical fatigue