Authors : J. A. Trujillo, Garcia Muriel and Ruben-Dario Ortiz-Ortiz
Abstract: An ac technique for the measurement of the thermoelectric power is introduced. We have developed a high resolution experimental set-up in the temperatures range 300-600 K. The method was used to measure the thermoelectric power (and specific heat) of the alumel alloy (95% Ni-2% Mn-2% Al-1% Si). Optical radiation was used to heat the sample periodically with a frequency of ω0/2π = 2.6 Hz which induces temperature modulation Tac in one end of the sample. The induced emf, Vac (T), between the illuminated and the obscure ends of the sample was then measured. The thermoelectric power S (T) was calculated from the relation Vac/Tac whose data points indicate an anomaly near 463 K. The temperature region of this anomaly agrees with that of the previously reported specific heat anomaly of alumel which is associated with the para-ferromagnetic phase transition in this Ni alloy.
J. A. Trujillo, Garcia Muriel and Ruben-Dario Ortiz-Ortiz, 2016. The Thermoelectric Power of Alumel at High Temperatures. Journal of Engineering and Applied Sciences, 11: 2304-2306.