Title :
High performance properties of sintered Bi2Te3-based thermoelectric material
Author :
Sugihara, S. ; Tomita, S. ; Asakawa, K. ; Suda, H.
Author_Institution :
Dept. of Mater. Sci. & Ceramic Technol., Shonan Inst. of Technol., Fujisawa, Japan
Abstract :
Bi/sub 2/Te/sub 3/-based thermoelectric materials have been studied for fabrication parameters and orientation effects. The powder particle sizes were less than 150 /spl mu/m and the mixtured grain sizes after sintering were observed in scanning electron microscope. As the results, electrical resistivity was 40% lower by reducing powders before pressing, and cold isostatic press took away the layer structures formed with pressing. The direction to the pressing and the measurements indicated lower resistivities (30-60%) for both p- and nBi/sub 2/Te/sub 3/, then Z values were 2.05 and 2.23 K/sup -1/ for those types, respectively. It should be notified that the composites of large and small grains will mitigate an enhancement of electrical resistivity and reduce thermal conductivity in a sintered specimen.
Keywords :
bismuth compounds; electrical resistivity; grain size; materials preparation; particle size; semiconductor materials; sintering; thermal conductivity; thermoelectricity; 150 mum; Bi/sub 2/Te/sub 3/; cold isostatic press; electrical resistivity; fabrication parameters; grain sizes; orientation effects; powder particle sizes; scanning electron microscope; sintered Bi/sub 2/Te/sub 3/-based thermoelectric material; thermal conductivity; Bismuth; Electric resistance; Electrons; Fabrication; Grain size; Powders; Pressing; Tellurium; Thermal conductivity; Thermoelectricity;
Conference_Titel :
Thermoelectrics, 1996., Fifteenth International Conference on
Conference_Location :
Pasadena, CA, USA
Print_ISBN :
0-7803-3221-0
DOI :
10.1109/ICT.1996.553254
