Phonon propagation in the disordered nanostructures at a high (about the Debye temperature or higher) temperature is considered. Scattering at the grain boundaries is assumed to be the main mechanism restricting the thermal conductivity. Influence of the structure (the grain size and its dispersion, the pore diameter and their volume concentration, and the intergrain interface structure) as well as temperature on the thermal conductivity is discussed.

• Received 12 March 2002

DOI:https://doi.org/10.1103/PhysRevB.66.134203