Thermal Conductivity, Thermal Diffusivity, and Specific Heat of Solids from a Single Experiment, with Application to Y1.98Nd0.02O3

In the absolute method for determining thermal conductivity K, the difference in temperature between two points along a rod is measured under conditions of steady-state flow of heat. The thermal diffusivity κ may also be determined from measurements of the time required for this temperature difference to decrease to half the steady-state value when the source of heat is removed. From K and κ data, the specific heat may be calculated, using the general relationship C=K/κρ, where ρ is the density. The technique permits determination of K, κ, and C with a single, small specimen having a wide range of K and κ. By observing simple experimental precautions, agreement to within 5%–10% has been obtained, for neodymium-doped yttrium oxide, between C values calculated from K and κ data and those derived from calorimetric data.