Title :
Preparation and thermoelectric properties of grain aligned (Ca,Bi) 3Co4O9 ceramics
Author :
Matsubara, I. ; Funahashi, R. ; Takeuchi, T. ; Zhou, Y.
Author_Institution :
Nat. Inst. of Adv. Ind. Sci. & Technol., Osaka, Japan
Abstract :
Effects of sintering process on the thermoelectric properties of (Ca,Bi)3Co4O9 ceramics have been investigated. We have prepared (Ca, Bi)3Co4O9 bulk materials using the methods of spark plasma sintering (SPS), hot pressing (HP), and a combination of them. Power factors of the SPS and HP samples at 700°C are 4.2×10-4 Wm-1 K-2 and 4.5×10-4 Wm-1 K-2, respectively. The combination of SPS and HP enables bulk ceramics (SPS-HP) to be high density, grain alignment, and low resistivity without any degradation of the thermoelectric power. The power factor and figure of merit of the SPS-HP sample attain to 5.7×10-4 Wm-1 K-2 and ZT=0.29 at 700°C, respectively
Keywords :
bismuth compounds; calcium compounds; electrical resistivity; hot pressing; sintering; thermal conductivity; thermoelectric power; (CaBi)3Co4O9; 700 C; ceramics; figure of merit; grain alignment; hot pressing; layered structure; power factor; resistivity; sintering; spark plasma sintering; thermoelectric power; Bismuth; Calcium; Ceramics; Coatings; Conducting materials; Conductivity; Plasma properties; Powders; Reactive power; Thermoelectricity;
Conference_Titel :
Thermoelectrics, 2001. Proceedings ICT 2001. XX International Conference on
Conference_Location :
Beijing
Print_ISBN :
0-7803-7205-0
DOI :
10.1109/ICT.2001.979852
