Design of high-temperature refractory high-entropy alloys

Refractory high-entropy alloys (RHEAs) have great potential for ultra-high temperature structural applications with the capability that is beyond the current Ni-based superalloys. Yet, excellent and balanced combinations of density, high-temperature strength, room-temperature ductility and oxidation resistance have not been achieved in this type of alloys so far.

In this project, a strategy of combining intermetallic phases and massive solid solutions is employed to design novel RHEAs. The intermetallic phases are formed in an in-situ way to maintain coherent or semi-coherent interfaces with low energy. The tunable phase components and microstructures allow us to fully tap their potentials in terms of mechanical properties and oxidation resistance. Advanced characterization methods from macroscopic to atomic-scales (OM, XRD, SEM/EDS/EBSD/ECCI, TEM and APT) are being used to investigate the structure-property relations.