About this Abstract |
| Meeting |
TMS Specialty Congress 2026
|
| Symposium
|
4th World Congress on High Entropy Alloys (HEA 2026)
|
| Presentation Title |
Efficient Design of Quinary Alumina-Forming Refractory Multi-Principal Element Alloys |
| Author(s) |
Melina A. Endsley, Chiyo McMullin, Collin S. Holgate, Gareth G. E. Seward, Akane Suzuki, Michael Worku, Noah R. Philips, 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 and Co-based superalloys in high temperature gas turbine engines due to their high melting temperatures. However, these alloys generally exhibit poor oxidation resistance, and will therefore require oxidation-resistant environmental barrier coatings, which historically have provided protection via formation of a dense alumina scale. Unfortunately, current alumina-forming alloys have inadequate temperature capabilities and are thermochemically incompatible with state-of-the-art RMPEAs, motivating the design of new oxidation-resistant coatings. Thermodynamic modeling (CALPHAD) and statistical methods were used to select promising two-phase alloys in the Nb-Mo-Ti-Al-Hf composition space, which were then synthesized via arc melting. Alloys that oxidize favorably to form a continuous and adherent alumina scale at 1400°C under isothermal conditions were identified. Differences in microstructure are confirmed via electron probe microanalysis (EPMA) and x-ray diffraction (XRD), and compared to explain the differences in oxidation behavior. |
| Proceedings Inclusion? |
Undecided |