Uncertainty evaluation on the freezing point of silver for thermocouple calibration

The freezing point of silver is realized using an open type cell. The uncertainty of the thermocouple calibration of this temperature was evaluated using Pt/Pd thermocouples. The sources of uncertainty estimated were stability and repeatability of the plateau, temperature distribution in the cell. impurity effect of the metal, surroundings pressure correction and hydrostatic pressure correction. The combined standard uncertainty is 7.8 mK.