Thermoelectric properties of thermoelectric modules consisted of porous FeSi2 based compounds fabricated by pressureless sintering

Single thermoelectric modules, which consist of porous p-type Fe0.9Mn0.1Si2 and n-type Fe0.94Co0.06Si2 compounds prepared by pressureless sintering, w ere fabricated and their thermoelectric properties were measured. It was fo und that the rate of the phase transition to beta-FeSi2 for the Fe0.94Co0.0 6Si2 compound was faster than that for the Fe0.9Mn0.1Si2 compound. The powe r factor of p- and n-type compounds fabricated with coarse powders (< 45 mu m) was similar to that of p- and n-type compounds fabricated with fine pow ders (2-3 mu m). A high power factor of all the p- and n-type compounds was obtained at 400-500 degrees C. The maximum power of the thermoelectric mod ules increased with increasing temperature difference and porosity. It is d emonstrated that the high maximum power of the module can be obtained with porous p- and n-type compounds fabricated by a pressureless sintering. (C) 2000 Elsevier Science S.A. All rights reserved.