Thermoelectric properties of p-type Bi-Sb-Te based material prepared by PIES method with conventional ball milling process

For the development of energy saving processes for producing thermoelectric materials, the PIES (Pulverized and Intermixed Elements Sintering) method is known as a suitable one. In this study, a high figure of merit p-type Bi-Sb-Te based thermoelectric material was obtained by the oxygen free PIES method. The electrical resistivity of p-type (Bi/sub 2/Te/sub 3/)/sub 0.175/(Sb/sub 2/Te/sub 3/)/sub 0.825/ material was reduced to 0.8/spl times/10/sup -5/ ohm m and Seebeck coefficient was obtained 2.4/spl times/10/sup -4/ V/K by fabrication in the oxygen free atmosphere process. The maximum ZT value was almost 1.0. Moreover, it was demonstrated that the improvement in figure of merit value was obtained even if the intermixed powder of elements was prepared by a conventional ball milling process in stead of the high energy ball milling process. The PIES methods using a low energy ball milling process is suitable for mass-production because of its cost efficiency.