Measurements of the thermal conductivity of thin films of magnetite

TLDR: In this paper, a steady-state method involving the use of a calibrated thermopile for determining the surface temperature of the oxide was developed for these measurements, and observed values of the thermal conductivity k0 range from 000625 to 00139 w cm−1 degc−1.

Abstract: Measurements have been made of the thermal conductivity of iron oxide layers in the `as-formed' condition for oxide thicknesses in the range 0027-048 mm over the temperature range 50-80°C. A steady-state method, involving the use of a calibrated thermopile for determining the surface temperature of the oxide, has been developed for these measurements. Observed values of the thermal conductivity k0 range from 000625 to 00139 w cm−1 degc−1, and are correlated as a function of oxide porosity P by the relation k0=00124±00018-915×10−5 P w cm−1 degc−1. Within the limited range of oxidation conditions used in the preparation of the specimens for this investigation, i.e. CO-CO2 gas containing up to 1200 p.p.m. by volume (v.p.m.) of water at temperatures from 400 to 600°C and pressures from 10 to 20 atm, there does not appear to be any correlation between the porosity and the oxidation conditions of the specimens.