Manipulation of σ{sub y}/κ ratio in single phase FCC solid-solutions
We investigate how to manipulate the ratio between thermal conductivity (κ) and yield strength (σ{sub y}) in face-centered cubic solid-solutions by varying the number of principal elements (NPEs) and temperature. The influence of NPEs on κ and its electronic (κ{sub e}) and lattice (κ{sub l}) contribution is evaluated using the Wiedemann–Franz law. Positive Δκ/ΔT and the highest κ{sub l}/κ{sub e} ratio in high-entropy alloys (HEAs) can be understood by considering severe lattice distortion and compositional complexity. Among the solid-solutions from Ni to quinary alloys, the NiCoFeCrMn HEA exhibits the lowest κ. However, σ{sub y} increases with increasing NPEs and decreasing temperature. Thus, the NiCoFeCrMn HEA exhibits the highest σ{sub y}/κ ratio, higher than those of representative cryogenic alloys, which can be distinctively increased with a decrease in temperature. These results would give us a guideline on how to manipulate properties using HEA design concept in order to develop idealized cryogenic materials.
- OSTI ID:
- 22594305
- Journal Information:
- Applied Physics Letters, Vol. 109, Issue 6; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
- Country of Publication:
- United States
- Language:
- English
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