From thermal conductive to thermal insulating: Effect of carbon vacancy content on lattice thermal conductivity of ZrC

Stability and structural properties of vacancy-ordered and -disordered ZrCx

“…3,4 The mechanical and thermodynamic properties of ZrC x are strongly dependent on the stoichiometry and structural ordering, 5 but much is unknown about the character of the vacancy ordering. As the variation of the thermophysical properties with vacancy concentration makes zirconium carbides a candidate for creating tuneable ceramics, 6,7 it is necessary to more closely explore the origins and consequences of the structural vacancy ordering in order to successfully fabricate materials for a specic application.…”

Electronic structure and thermal conductivity of zirconium carbide with hafnium additions

“…The purpose of this paper is to use theoretical methods to study the effect of hafnium content on the electronic structure and lattice thermal conductivity of (Zr,Hf)C solid solutions. Note that some of the results for pure ZrC used for comparison in the present study were from our previous study on the effect of carbon vacancy content on the thermal properties of ZrC x ceramics 34 . The previously published results are shown in Figures 1A, 6A, and 7A as well as in Table 1.…”

First‐principles study of the thermal properties of Zr2C and Zr2CO

“…The calculated elastic constants and Poisson's ratio for both compounds are listed in Table 1 with values from other reports 22,28 included for comparison. The elastic constants are a direct reflection of bond strength.…”

“…Figure 4 shows the temperature‐dependent lattice thermal conductivities of Zr 2 C and Zr 2 CO that were calculated using a combination of first‐principles calculations and the Debye–Callaway model. The effects of Zr isotopes, grain boundaries, and Umklapp and normal processes were considered in these calculations as detailed in our previous studies 22,23 . The lattice thermal conductivities for both ordered compounds at elevated temperatures are significantly lower than those at room temperature due to phonon scattering 25 .…”

“…Once phonon frequencies over the first Brillouin zone are known, the energy of the phonon system ( E ) can be obtained from the canonical distribution in statistical mechanics using the harmonic approximation. Lattice thermal conductivities were predicted using the Debye–Callaway model as reported in our previous papers 22,23 …”