Variations of Thermoelectric Power of Ni–Fe Invar Alloys with Temperature and Magnetic Field

The thermoelectric powers of Ni–Fe alloys containing 30∼50 at.%Ni and pure Ni have been measured from 77 K to the Curie temperature as a function of the external magnetic field. The temperature dependence of the magnetic thermopower of the alloys with low Ni-concentration has been interpreted, with reasonable fitting parameters, in terms of Kasuya's relation based upon the s-d exchange interaction model. A remarkable decrease in the thermopower due to the magnetic field was observed in the alloys over a wide temperature range. This magnetic field effect has been discussed from Kasuya's relation.