Accession Number : AD0621484

Title :   INSTABILITY OF REFRACTORY METAL THERMOCOUPLES.

Descriptive Note : Interim rept.,

Corporate Author : NAVAL RESEARCH LAB WASHINGTON D C

Personal Author(s) : Walker,B. E. ,Jr. ; ewing,C. T. ; Miller,R. R.

Report Date : 26 MAR 1965

Pagination or Media Count : 18

Abstract : Thermoelectric instabilities of some refractory metal thermocouples were studied in the temperature range 1000 to 2000C under vacuum and neutral atmospheres. The sources of instability were found to complex, involving contamination from ceramic protection tubes and furnace environments, preferential volatilization, and various thermal anomalies such as recrystallization and phase changes in the refractory thermoelements. Refractory thermocouples and thermoelements were studied under a variety of conditions, and emf changes associated with each were noted. Recommendations were made for the selection and application of these thermocouples to attain maximum thermoelectric stability. (Author)

Descriptors :   (*THERMOCOUPLES, STABILITY), (*REFRACTORY METALS, THERMOCOUPLES), THERMOELECTRICITY, CONTAMINATION, COMPATIBILITY, HIGH TEMPERATURE, VACUUM, CERAMIC MATERIALS, SELECTION, FURNACES, RECRYSTALLIZATION, PHASE STUDIES, TUNGSTEN, RHENIUM, MOLYBDENUM

Distribution Statement : APPROVED FOR PUBLIC RELEASE