Establishing scale realisation equivalence at high-temperature (2000 K) using a Pt-C eutectic point.

Project Description

In a first step, the two laboratories exchange information about cell construction and implementation, taking advantage of the knowledge acquired during the HIMERT project (development, characterisation and comparison of a series of metal-carbon eutectic points in several European laboratories, including LNE-INM).

The cells constructed in each laboratory are studied and have an ITS-90 temperature determination and are then swapped to be studied in the partner laboratory.

The assessment of the capabilities of a single eutectic point to help comparing the realisation of the scale between two laboratories is one of the aims of this study. Of course, this comparison will be affected by the uncertainty in scale realization. Moreover, differences between the cells are to be taken into account and their determination in a single furnace and in a very short time frame (minimising any effect of the radiation thermometer instability) is planned.

Final Report 2010-03-26

After having compared Pt-C cells and determined the temperature differences between the cells, the two laboratories have compared, as a final stage of the common work, two Co-C cells and two Re-C cells.
The difference observed between the Co-C cells melting temperatures was of only a few hundredths of a degree. It however reached several tenths of a degree between the Re-C cells.
A joint paper is in preparation to sum up the results of the comparison of cells and scales at the Co-C and Re-C temperatures.