Effects of Hot-Press on Ca3Co4O9 Calcium Cobalt Oxide Thermoelectric Materials

Abstract

In the present Study, the thermoelectric Ca₃Co₄O₉ Calcium Cobalt Oxide powders were synthesized by a conventional methods and pressed with  Indian made  Hot Press based on  high pressure and  temperature simultaneously  which  shows low strain rate,materials  sintering at 1173 K for  30 minutes at 10-3 vacuum in a chamber at pressure 86Mpa. After many trial experiment, We discussed the best parameter which is suit for Calcium cobalt oxide pellets, excellent for thermoelectric measurements. For the prepared Calcium cobalt oxide circular pellets, phase purity and microstructure are analyzed. XRD shows that no unwanted reaction has occurred between the sintering process. From Field effect scanning electron micrographs, it is observed that compactness binds molecules show randomly oriented grains. Density measured by Archimedes principle shows approx 99% with theoretical density.