Abstract
The stability of coherent L12-ordered Ni3(Al,Ti) intermetallic precipitates was studied in Fe-14Cr-32Ni-3Nb-(3-4)Al-(1-3)Ti (wt.%) based alumina-forming austenitic stainless alloys. Computational thermodynamics predicted the formation of multi-intermetallic phases, including L12 and β-NiAl (B2), in an austenite matrix below ∼900°C. Microstructure characterization revealed a significant stabilization of the L12 phase by Zr addition, with the amount of L12 increasing with increasing Ti addition. However, the Ti addition also degraded the oxidation resistance. Further additions of C and B successfully improved both creep and oxidation properties.
| Original language | English |
|---|---|
| Pages (from-to) | 816-819 |
| Number of pages | 4 |
| Journal | Scripta Materialia |
| Volume | 69 |
| Issue number | 11-12 |
| DOIs | |
| State | Published - Dec 2013 |
Funding
Research sponsored by the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Industrial Technologies Program (currently the Advanced Manufacturing Office), and the U.S. Department of Defense, Defense Advanced Research Projects Agency (DARPA), under contract DE-AC05-00OR22725 with UT-Battelle, LLC. ORNL’s Shared Research Equipment (ShaRE) User Program, the Office of Basic Energy Sciences, the U.S. Department of Energy, is also acknowledged.
Keywords
- Alumina
- Austenitic steels
- Creep
- Intermetallic compounds
- Oxidation