About this Abstract |
| Meeting |
2026 TMS Annual Meeting & Exhibition
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| Symposium
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Environmental Degradation of Multiple Principal Component Materials
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| Presentation Title |
Tuning the oxidation behavior of Nb-Mo-Ti-Al-X alloys at intermediate temperatures |
| Author(s) |
Melina A. Endsley, Collin S. Holgate, Kirmina M. Monir, Eddy L. Rao, Michael Worku, Carlos G. Levi, Tresa M. Pollock |
| On-Site Speaker (Planned) |
Melina A. Endsley |
| Abstract Scope |
Refractory multi-principal element alloys (RMPEAs) are promising candidates for replacing Ni-based superalloys in gas turbine engines due to their exceptional strength at high temperatures. However, these alloys generally exhibit poor oxidation resistance, and will therefore require overlay protective coatings, which historically have gained protection from the formation of an alumina scale. Unfortunately, current alumina-forming bond coats have inadequate temperature capabilities and are thermochemically incompatible with state-of-the-art RMPEAs, motivating the design of new environmental coatings. Previous work has explored the Nb-Mo-Ti-Al composition space, where new alloys formed a continuous and adherent alumina scale at 1400°C, but performed poorly at 1200°C, experiencing runaway oxidation. To mitigate this intermediate temperature oxidation, alloy variants with additions of 5 at% Hf, Cr, or Si were synthesized and tested. The resultant oxidation behavior and microstructural differences are analyzed via various characterization techniques, including EPMA and TEM. Oxidation kinetics, assessed by TGA, will also be discussed. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Environmental Effects, High-Temperature Materials, Other |