RESEARCH AND DEVELOPMENT ON ADVANCED GRAPHITE MATERIALS VOLUME ⅩⅩⅠ CARBON ARC IMAGE FURNACE STUDIES OF GRAPHITE

摘要

Measurements obtained using a carbon arc image furnace indicate that the spectral reflectance and emissivity of carbon and graphite samples in the visible region of the spectrum are strongly dependent on surface finish, but are independent of temperature to at least 3000°K, regardless of surface finish. Discrepancies with other measurements of emissivity are indicated to be caused by errors in the measurement of surface temperature, due to thermal gradients.nInformation has been obtained with the carbon arc image furnace indicating that the thermal conductivity of surface material depends strongly on surface finish and is smaller than the conductivity of substrate material.nThis technical documentary report has been reviewed and is approved.