Progress with the development of high temperature fixed-points in the eu through the himert project projet européen himert : le point sur la réalisation de points fixes à haute température

The EU FP5 funded research project HIMERT (Novel High temperature Metal-carbon Eutectic fixed points for Radiation Thermometry, Radiometry and Thermocouples) aims to develop high temperature fixed points above the freezing point of copper to approximately 2500 °C with a repeatability of less than 0.1°C. NPL and BNM-INM have constructed fixedpoint blackbody sources, while BNM-LNE has constructed cells up to 1950 °C (Ru-C) for the calibration of contact sensors. PTB will perform absolute radiometry of the cells constructed by NPL and BNM-INM. Pt-Pd thermocouple studies will be undertaken by PTB and BNM-LNE. Also a major materials compatibility study has been undertaken by BNM-LNE to identify thermocouple sheath materials that are compatible with graphite to 1950 °C. The University of Valladolid is investigating the background physics of the eutectic process and seeking to develop physically realistic models. The two industrial companies will test whether improved traceability at lower uncertainties can be achieved by using metal-carbon eutectics. This paper describes the HIMERT project and current progress.