Abstract
The thermal conductivities of three specimens of well-oriented, annealed pyrolytic graphite have been measured over the temperature range 100–900°K. The conductivity parallel to the deposition plane is analysed in terms of mean free paths using the semi-continuum model of Komatsu and Nagamiya. An expression is derived for the phonon mean free path due to Umklapp scattering. A temperature independent phonon mean free path results from boundary scattering. The conductivity perpendicular to the deposition plane has been fitted to the Leibfried-Schlomann equation.