Abstract
A nearly single-phase θ-Al2O3 scale has been grown on two FeCrAl alloys, according to a time-temperature-transformation relationship for the formation of external alumina scales. SIMS sputter depth profiles of the 18O 16O distribution consistently indicate that θ-Al2O3 scales grow primarily by the outward transport of Al. This mechanism is consistent with the observed scale microstructure and is significantly different from tracer profiles for α-Al2O3 scales.
Original language | English |
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Pages (from-to) | 99-107 |
Number of pages | 9 |
Journal | Solid State Ionics |
Volume | 78 |
Issue number | 1-2 |
DOIs | |
State | Published - May 1995 |
Externally published | Yes |
Funding
The authors are very grateful to J. Doychak at NASA Lewis, W. Lipscomb at Into and B. Jonsson at Kanthal for providing materials. Among our colleagues at MIT, thanks goes to J. Adario for his assistancew ith the GAXRD measurements,a nd to G. Arndt and R. Perilli for assistancew ith the oxidation equipment and tracer experiments.T he Electric Power Research Institute provided financial support for this research under contract #RP242644. The ASE Facility and SIMS are supportedb y NSF grant #DMR90-22933. BAP and LWH dedicatet his paper to our friend and co-author John R. Martin, whose untimely death on August 15, 1994 cut short the productive career of a talented scientist.
Keywords
- O/SIMS
- Oxide scales
- Phase transformation