Microstructure and thermal conduction properties involving thermal dif
fusivity and conductivity of composite, Al2O3-Ag, were investigated. T
he Ag particles observed in the composites were spread sporadically th
roughout the composite with inclusion size increasing with Ag content,
rather than forming a network of thin film foil. Thermal conductivity
of the composite increased with Ag content and followed composite the
ory prediction with a negligible influence of interfacial contact resi
stance. The temperature dependence of the thermal conductivity became
less pronounced with increasing Ag content reflecting the nature of el
ectron contribution in Ag rather than the typical phonon contribution
in polycrystalline Al2O3. The lower composite conductivity at higher A
g contents as compared to theoretical predictions is due primarily to
the residual pore phase, associated with the cavity formation for the
composite containing 10 vol.% Ag.