About this Abstract |
Meeting |
2nd World Congress on High Entropy Alloys (HEA 2021)
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Symposium
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2nd World Congress on High Entropy Alloys (HEA 2021)
|
Presentation Title |
ON DEMAND: Superior High-temperature Strength in a Refractory High-entropy Alloy |
Author(s) |
Rui Feng, Bojun Feng, Michael C. Gao, Chuan Zhang, Joerg C. Neuefeind, Jonathan D. Poplawsky, Yang Ren, Ke An, Michael Widom, Peter K. Liaw |
On-Site Speaker (Planned) |
Rui Feng |
Abstract Scope |
Refractory high-entropy alloys (RHEA) show promising applications at high temperatures. However, achieving high strengths at elevated temperatures above 1,173K is still challenging due to heat softening. Using intrinsic material characteristics as the alloy-design principles, a single-phase body-centered-cubic (BCC) RHEA with high-temperature strengths (beyond 1,000 MPa at 1,273 K) is designed, superior to other reported RHEAs as well as conventional superalloys. The origin of the high-temperature strength is revealed by in-situ neutron scattering, transmission-electron microscopy, and first-principles calculations. The designed RHEA’s elevated-temperature strength retention up to 1,273 K arises from its large local lattice and modulus misfits, the insensitive temperature dependence of elastic constants, and the dominance of non-screw character dislocations caused by the strong solute pinning, which makes the solid-solution strengthening pronounced. The alloy-design principles and the insights in this study pave the way to design RHEAs with outstanding high-temperature strength. |
Proceedings Inclusion? |
Undecided |