Phonon thermal conductivity of nanograined zirconium diboride: molecular dynamics study

In this study, the characteristics of phonon transport in single-crystal and nanograined zirconium diboride have been examined using the molecular dynamics method. In the case of single-crystal ZrB2 the anisotropy of the phonon thermal conductivity decreased gradually with increasing temperature. The results demonstrate that a reduction in grain size in nanograined ZrB2 leads to a decline in thermal conductivity. At a grain size of 1 nm, further reduction does not affect the thermal conductivity of the material. The findings are explained in terms of the scattering of heat carriers at the interfaces and the amorphization of the grain structure.