Concentrated refractory alloys are an emerging class of alloys that have the potential to push the temperature capability of current metallic solutions.  While these alloys have been shown to have higher specific strength than Ni-base superalloys at elevated temperatures, they have been severely limited by environmental attack.  Recent work has highlighted compositions that have shown increased oxidation resistance in comparison to conventional refractory alloys, which is promoted by the formation of complex refractory oxides.  While this work has identified some beneficial prototype oxide structures, more fundamental work is required to deliver inherent oxidation resistance for structurally sound and ductile concentrated alloys.  We are interested in foundational work focused on inherent oxidation of these complex systems including:  understanding of oxidation thermodynamics and kinetics, identification of protective oxide products and predictive oxidation models.  We are also interested in exploring the use of coatings and surface treatments to increase oxidation resistance while minimally influencing bulk response.

T.M. Butler, “High Entropy Alloys: Oxidation”, Encyclopedia of Materials: Metals and Alloys (2022) 2, 522-532.

 T.M. Butler, O.N. Senkov, T.I. Daboiku, M.A. Velez, H.E. Schroader, L.G. Ware, M.S. Titus, “Oxidation behaviors of CrNb, CrNbTi, and CrNbTaTi concentrated,” Intermetallics 140 (2021), 107374.

T.M. Butler, K.J. Chaput, “Native Oxidation Resistance of Al20Nb30Ta10Ti30Zr10 Refractory Complex Concentrated Alloy (RCCA),” Journal of Alloys and Compounds (2019) 787, 606-617.