Texture and thermoelectric properties of hot-extruded Bi2Te3 compound

This paper concerns about the applicability of extrusion process to fabricate Bi2Te3 thermoelements. High duality products were obtained by hot-extrusion method and their texture and the thermoelectric properties measured. The hot-extruded material had very fine grains derived from dynamic recrystallization. It was found that hot-extruded material has a ring-like texture in which the normal to the basal plane orients to the radial direction and [110] orients to the extrusion direction. Figure of merit of the extrudate increases with decreasing extrusion temperature and the value of the product extruded at 693 K showed a value corresponding to about 88% of unidirectionally solidified elements. (C) 2000 Elsevier Science S.A, All rights reserved.