Design of refractory multi-principal-element alloys for high-temperature applications
Abstract
Refractory multi-principal-element alloys (RMPEAs) exhibit high specific strength at elevated temperatures (T). However, current RMPEAs lack a balance of room-temperature (RT) ductility, high-T strength, and high-T creep resistance. Using density-functional theory methods, we scanned composition space using four criteria: (1) formation energies for operational stability: $$-150\le {E}_{{\rm {f}}}$$ − 150 ≤ E f ≤ +70 meV per atom; (2) higher strength found via interstitial electron density with Young’s moduli E > 250 GPa; (3) inverse Pugh ratio for ductility: G/B Tm > 2500 °C. Using rapid bulk alloy synthesis and characterization, we validated theory and down-selected promising alloy compositions and discovered Mo72.3W12.8Ta10.0Ti2.5Zr2.5 having well-balanced RT and high-T mechanical properties. This alloy has comparable high-T compressive strength to well-known MoNbTaW but is more ductile and more creep resistant. It is also superior to a commercial Mo-based refractory alloy and a nickel-based superalloy (Haynes-282) with improved high-T tensile strength and creep resistance.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Aug 10, 2023
- Source ID
- 10.1038/s41524-023-01095-4
Entities
People
- Daniel Miracle
- Duane D. Johnson
- Gaoyuan Ouyang
- John H. Perepezko
- Jun Cui
- Matthew J Kramer
- Oleg N. Senkov
- Prashant Singh
- Ranran Su
Organizations
- Office of Basic Energy Sciences
- Office of Energy Efficiency and Renewable Energy
- United States Air Force
- United States Department of Energy