| Author(s) |
David Beaudry, Michael J. Waters, Gianna M. Valentino, Daniel L. Foley, Nathan Smith, Elaf Anber, Yevgeny Rakita, Charlie J. Brandenburg, Jean-Philippe Couzinie, Loic Perriere, Toshihiro Aoki, Keith E. Knipling, Patrick G. Callahan, Benjamin W.Y. Redemann, Tyrel M. McQueen, Elizabeth J. Opila, Christopher Wolverton, James M. Rondinelli, Mitra L. Taheri |
| Abstract Scope |
Refractory multiprincipal element alloys (RMPEAs) offer superiority to incumbent high-temperature structural alloys due to high melting points and retained strength at elevated temperatures. Of this class of alloys, those containing Group IV and V elements possess adequate ductility, low density, and the necessary formability. However, these elements have dramatically different interactions with oxygen, which creates uncertainty in predicting oxide evolution and in alloy design for oxidation resistance. We used high fidelity characterization and Monte Carlo simulations to decipher the complex sub-surface phase evolution during high-temperature oxidation of Group IV-V RMPEAs. We found that a refined hierarchical microstructure of phase-separated oxides form, which leads to a hardness increase of over 600% while preserving the ductility of the base metal. High-throughput computational screening identified doping elements that would capitalize on our fundamental phase evolution findings to improve oxidation resistance and mechanical properties in these alloys. |