Abstract
The n-type Bi/sub 2/Te/sub 2.85/Se/sub 0.15/ compounds were fabricated by the hot extrusion under in the temperature range of 300 to 440/spl deg/C under an extrusion ratio of 20:1. The microstructure and thermoelectric properties of the compounds were studied. It was found that the compounds was highly dense. The density was increased with increasing temperature. Also, equiaxed fine grains (/spl sim/1.0 /spl mu/m) were formed because dynamic recrystallization occurred during the extrusion. The hot extrusion gave rise to a slightly preferred orientation of grains. The small grain size and preferred orientation of grains and the high density contributed to an improvement in the thermoelectric properties. The highest figure of merit (2.62/spl times/10/sup -3//K) was obtained at 440/spl deg/C. In addition, the Sbl/sub 3/ dopants significantly increased the figure of merit. The values of the figure of merit for 0.05 wt% Sbl/sub 3/-doped Bi/sub 2/Te/sub 0.85/Se/sub 0.15/ compounds hot extruded at 440/spl deg/C was 3.05/spl times/10/sup -3//K.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call