The concept of multi-principal component has created promising opportunities for the development of novel high-entropy ceramics for extreme environments encountered in advanced turbine engines, nuclear reactors, and hypersonic vehicles, as it expands the compositional space of ceramic materials with tailored properties within a single-phase solid solution. The unique physical properties of some high-entropy carbides and borides, such as higher hardness, high-temperature strength, lower thermal conductivity, and improved irradiation resistance than the constitute ceramics, have been observed. These promising properties may be attributed to the compositional complexity, atomic-level disorder, lattice distortion, and other fundamental processes related to defect formation and phonon scattering. This manuscript serves as a critical review of the recent progress in high-entropy carbides and borides, focusing on synthesis and evaluations of their performance in extreme high-temperature, irradiation, and gaseous environments.
- Award ID(s):
- 1902069
- NSF-PAR ID:
- 10382550
- Date Published:
- Journal Name:
- Annual Review of Materials Research
- Volume:
- 51
- Issue:
- 1
- ISSN:
- 1531-7331
- Page Range / eLocation ID:
- 165 to 185
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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