Abstract
Very few data on the specific heat capacity of thermocouple materials over a wide temperature range exist. We measured the specific heat capacities at constant pressure of chromel® and alumel® of K-type thermocouples with a power-compensated differential scanning calorimeter in the temperature range 304K-574K. First, we measured the specific heat capacity of synthetic sapphire as a standard reference material to determine the optimum heating rate. Next, we measured the specific heat capacity of high-purity copper as a standard reference material to determine the optimum heat capacity ratio of the specimen and an aluminium pan and to estimate the measurement accuracy of the present calorimeter. Lastly, we measured the specific heat capacities of chromel® and alumel® using the optimum heating rate and the optimum heat capacity ratio. The measured specific heat capacity was compared with the existing published data. The Curie temperature of alumel and the applicability of the Kopp-Neumann law for the measured specific heat capacity were also discussed.
