Mechanical and thermoelectric environmental evolution properties of Bi2Sr2Co1.8Ox ceramics textured by laser floating zone technique

Bi2Sr2Co1.8Ox ceramics have been synthesized through solid-state reaction methods and directionally grown from the melt by laser floating zone technique. Mechanical and thermoelectric characteristics of this material were determined by three point bending tests and the four probe technique, respectively. The mechanical and thermoelectric properties of Bi2Sr2Co1.8Ox were determined as a function of the environmental conditions, air and water. Flexural strength data show that textured materials possess a high degradation resistance due to the low porosity of the external part of the rods (similar to 65 mu m), which avoids water infiltration and, as a consequence, the internal degradation. Moreover, power factor values are maintained practically unchanged for the samples immersed in water for 24 h.