Hot corrosion stability of double perovskite and pyrochlore in suphate solution of vanadates or chlorides at 900 °C

Abstract

Double perovskites, pyrochlores are having matching thermal expansion co-efficient with bond coat and may act as candidate materials for an intermediate layer between bond coat and top coat in Thermal Barrier Coatings. Hot corrosion stability of double perovskites and pyrochlores is also important for enhanced thermal cycle life. Based on these issues, systematic studies were conducted to find the hot corrosion stability of double perovskites and pyrochlores. The results revealed that, double perovskites and pyrochlores were undergone destabilization in the Na<inf>2</inf>SO<inf>4</inf>+50 wt.% V<inf>2</inf>O<inf>5</inf> and Na<inf>2</inf>SO<inf>4</inf>+10 wt.% NaCl environments at 900 °C. The implications of these findings addresses the key issues related hot corrosion mechanisms and give a pathway to developing newer materials. This study clearly indicates the destabilization of both double perovskites and pyrochlores in vanadium and chloride environments at 900 °C. © (2015) Trans Tech Publications, Switzerland.