Publication Date
7-2019
Department
Ames Laboratory; Physics and Astronomy
Campus Units
Physics and Astronomy, Ames Laboratory
OSTI ID+
1527127
Report Number
IS-J 9895
DOI
10.1111/jace.16295
Journal Title
Journal of the American Ceramic Society
Volume Number
102
Issue Number
7
First Page
4344
Last Page
4352
Abstract
The formation possibility of (Hf0.2Zr0.2Ta0.2Nb0.2Ti0.2)C high‐entropy ceramic (HHC‐1) was first analyzed by the first‐principles calculations, and then, it was successfully fabricated by hot‐pressing sintering technique at 2073 K under a pressure of 30 MPa. The first‐principles calculation results showed that the mixing enthalpy and mixing entropy of HHC‐1 were −0.869 ± 0.290 kJ/mol and 0.805R, respectively. The experimental results showed that the as‐prepared HHC‐1 not only had an interesting single rock‐salt crystal structure of metal carbides but also possessed high compositional uniformity from nanoscale to microscale. By taking advantage of these unique features, it exhibited extremely high nanohardness of 40.6 ± 0.6 GPa and elastic modulus in the range from 514 ± 10 to 522 ± 10 GPa and relatively high electrical resistivity of 91 ± 1.3 μΩ·cm, which could be due to the presence of solid solution effects.
DOE Contract Number(s)
AC02‐07CH11358
Language
en
Department of Energy Subject Categories
36 MATERIALS SCIENCE
Publisher
Iowa State University Digital Repository, Ames IA (United States)