About this Abstract |
| Meeting |
MS&T25: Materials Science & Technology
|
| Symposium
|
Advances in Refractory High Entropy Alloys and Ceramics
|
| Presentation Title |
Creep Behavior of a Precipitation-Strengthened
A2-B2 Refractory High Entropy Alloy |
| Author(s) |
Daniel Schliephake, Liu Yang, Sandipan Sen, Alexander Kauffmann, Raja J. Vikram, Stephan Laube, Aparajita Pramanik, Ankur Chauhan, Martin Heilmaier |
| On-Site Speaker (Planned) |
Daniel Schliephake |
| Abstract Scope |
Refractory high entropy alloys (RHEAs) consisting of a disordered A2 matrix and ordered B2 precipitates mimic the microstructures of state-of-the-art, Ni-based superalloys with A1 matrix and ordered L1<sub>2</sub> precipitates. However, systematic studies on their creep behavior are still scarce.
The creep behavior of polycrystalline 27.3Ta-27.3Mo-27.3Ti-8Cr-10Al, consisting of a disordered A2 matrix and B2 precipitates, is systematically investigated at temperatures of 1000 °C and above. Minimum creep rates are found to be significantly lower than for single phase A2 and B2 RHEAs and comparable to those of state-of-the-art single crystalline A1-L1<sub>2</sub> CMSX-4. This is particularly remarkable given the polycrystalline nature of our alloy and the extremely high homologous particle solvus temperature of 0.98 T<sub>S</sub> compared to 0.85 T<sub>S</sub> for CMSX-4. Consistent with a positive lattice misfit, directional coarsening of the precipitates in 27.3Ta-27.3Mo-27.3Ti-8Cr-10Al perpendicular to the compression direction is revealed after creep in grains with 〈100〉 near the compression direction. |