Abstract
A bar of pyrolytic graphite, grown at a constant surface temperature of 2200°c by resistance heating of the substrate, was cleaved into a number of thin sections; crystallographic and a-direction thermal and electrical measurements were made as a function of distance through the deposit. These properties were found to vary in a systematic way consistent with the increased substrate temperature to be expected in this method of growth. The temperature profile through the deposit was estimated, yielding a substrate temperature of 3050°c for a deposit 24 mm thick. Comparison of the electrical properties with other workers' results on pyrolytic graphites annealed at known temperatures gives adequate confirmation of the estimated temperatures and shows that resistance-grown graphites may be used to measure a-direction properties of material effectively annealed at temperatures much in excess of the surface deposition temperature.
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