Title

From Thermal Conductive to Thermal Insulating: Effect of Carbon Vacancy Content on Lattice Thermal Conductivity of ZrCₓ

Abstract

Lattice thermal conductivities of zirconium carbide (ZrCx, x = 1, 0.75 and 0.5) ceramics with different carbon vacancy concentrations were calculated using a combination of first-principles calculations and the Debye-Callaway model. The Grüneisen parameters, Debye temperatures, and phonon group velocities were deduced from phonon dispersions of ZrCx determined using first-principles calculations. In addition, the effects of average atomic mass, grain size, average atomic volume and Zr isotopes on the lattice thermal conductivities of ZrCx were analyzed using phonon scattering models. The lattice thermal conductivity decreased as temperature increased for ZrC, ZrC0.75 and ZrC0.5 (Zr2C), and decreased as carbon vacancy concentration increased. Intriguingly, ZrCx can be tailored from a thermal conducting material for ZrC with high lattice thermal conductivity to a thermal insulating material for ZrC0.5 with low lattice thermal conductivity. Thus, it opens a window to tune the thermal properties of ZrCx by controlling the carbon vacancy content.

Department(s)

Materials Science and Engineering

Second Department

Nuclear Engineering and Radiation Science

Comments

National Science Foundation, Grant DMR 1742086

Keywords and Phrases

First-Principle Calculations; Lattice Thermal Conductivity; Theoretical Study; Zirconium Carbide

International Standard Serial Number (ISSN)

1005-0302

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2021 Elsevier, All rights reserved.

Publication Date

20 Aug 2021

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