Realization and Dissemination of the International Temperature Scale of 1990 (ITS-90) above 962°C at the National Research Council (NRC) Canada

摘要

Above 962 °C, the ITS-90 is realized at NRC by a standard radiation thermometer with a known spectral responsivity and a silver freezing-point blackbody. Together with Planck's law, the temperature scale can be extrapolated to temperatures in excess of 2500 °C albeit with uncertainties that increase with higher temperatures. This realization can then be disseminated to other radiation thermometers via a variable-temperature blackbody for use in, for example, calibration laboratories. In the future, it is expected that new high-temperature fixed points with transition temperatures exceeding 3000 °C will allow an interpolated high-temperature realization and lower uncertainties.