Paper Title
Physical and Thermoelectric Properties of YBa2Cu3O7-X-NaYCoO2 Segmented Oxide Ceramic Prepared by Hot-Pressing Method

Abstract
Segmented YBa2Cu3O7-x-NayCoO2 (YBCO-NCO) ceramic was prepared by hot pressing method with the sintering condition of 850C for 1 h at a pressure of 70 MPa in Ar atmosphere. Away from the interface, single phase of YBCO and NCO was obtained. The scanning electron micrographs of segmented indicated that the two layers strongly bonded with the relative density 95%. The peak electrical conductivity of 2.6 × 104 (m)-1 was obtained at 600 K. The Seebeck coefficient of the segmented YBCO-NCO ceramic showed a maximum value of 155 V/K at 800 K. The thermal conductivity values ranged from 0.72-1.25 W/mK. The maximum ZT value of 0.4 was also obtained at 800 K. Keyword - Hot Pressing, Segmented Ceramic, Sodium Cobalt Oxide, Yttrium Barium Copper Oxide.