Abstract
Fatigue-crack-propagation (FCP) thresholds in a nickel-base superalloy at high frequencies and temperatures were investigated. Two different heat treatments were investigated, one yielding a relatively coarse grain size of 55 μm and another yielding a fine grain size of 6 μm. Tests were conducted at 100 Hz and 1000 Hz and at load ratios between 0.3 to 0.7. Scanning electron microscopy (SEM) was used to determine quantitative measures of fracture-surface roughness. Results showed that the roughness of the fracture surface increased as the load ratio was increased for both microstructures.
| Original language | English |
|---|---|
| Article number | 28 |
| Pages (from-to) | 1949-1962 |
| Number of pages | 14 |
| Journal | Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science |
| Volume | 33 |
| Issue number | 7 |
| DOIs | |
| State | Published - 2002 |
| Externally published | Yes |
Funding
This work was supported by the MURI on “High Cycle Fatigue,” funded at Michigan Technological University by the Air Force Office of Scientific Research, Grant No. F49620-96-1-0478, through a subcontract from the University of California at Berkeley. We thank Dr. David L. David-son, retired from Southwest Research Institute, for helpful comments on this manuscript.