Accession Number : ADA321913
Title : Emissivity and Temperature Scale for Vacuum Heated Uranium,
Corporate Author : TECHNICAL INFORMATION SERVICE (AEC) OAK RIDGE TN
Personal Author(s) : Wahlin, H. B.
PDF Url : ADA321913
Report Date : 12 SEP 1944
Pagination or Media Count : 3
Abstract : In this investigation the true and apparent temperatures were determined for uranium which had been heated in a vacuum of 10(exp -6)mm or lower for a period of 300 hours or more. The procedure was to take flat strips of the metal and roll them into hollow cylinders about 3 mm in diameter and 12 cm long. A hole 1/2 mm in diameter was drilled in the side of the cylinders. These were then mounted in a tube connected to a pumping system and evacuated. During the heat treatment continuous pumping was carried on. At the start the emissivity, calculated from the temperatures of the metal surface and the temperature of the hole (which gives the true temperature), was higher than the final value. Continuous heating at temperatures between 1250 and 1300 deg K will clean the surface and lower the emissivity. This cleaning, it seems, may be speeded up by turning the heating current off and allowing the cylinder to cool through the recalescence points.
Descriptors : *TEMPERATURE, *VACUUM, *HEATING, *URANIUM, *EMISSIVITY, METALS, COOLING, HEAT TREATMENT, SURFACES, CYLINDRICAL BODIES, CLEANING, PUMPING.
Subject Categories : Inorganic Chemistry
Distribution Statement : APPROVED FOR PUBLIC RELEASE