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Title: A new technique for direct traceability of contact thermometry Co-C eutectic cells to the ITS-90

The eutectic Co-C melting point is a promising system to serve as a thermometric fixed-point in the temperature range above 1084.62 °C (copper freezing point). During the last decade, LNE-Cnam has developed and characterized some fixed-point devices, based on eutectic Co-C alloy, for applications to contact and radiation thermometry. Above 962 °C, the ITS-90 is realized by radiation thermometry by the extrapolation from a Ag, Au or Cu fixed point using the Planck law for radiation. So the only way for assigning a temperature in the scale to a Co-C cell (∼1324 °C) is by radiation thermometry. An indirect method is commonly used to assign a temperature to a high-temperature fixed point (HTFP) cell designed for contact thermometry is to fill a pyrometric cell with the same mixture as the contact thermometry cell. In this case, the temperature assigned to the pyrometric cell is attributed to the contact cell. This paper describes a direct method allowing the determination of the melting temperature realized by a 'contact thermometry' Co-C cell by comparison to a 'radiation thermometry' Co-C cell whose melting temperature was assigned in accordance to the scale by extrapolation from the Cu point. In addition, the same Co-C cell ismore » studied with a standard Pt/Pd thermocouple.« less
Authors:
; ; ; ;  [1]
  1. Laboratoire Commun de Métrologie LNE-Cnam, 61 rue du Landy 93210 La Plaine Saint Denis (France)
Publication Date:
OSTI Identifier:
22218022
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 1552; Journal Issue: 1; Conference: 9. international temperature symposium, Los Angeles, CA (United States), 19-23 Mar 2012; Other Information: (c) 2013 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; CARBON; COBALT; COMPARATIVE EVALUATIONS; COPPER; EUTECTICS; EXTRAPOLATION; MELTING POINTS; MIXTURES; PLANCK LAW; PYROMETERS; TEMPERATURE DEPENDENCE; TEMPERATURE MEASUREMENT; THERMOCOUPLES; THERMOMETERS