Phase Transition and Failure at High Temperature of Bismuth-Layered Piezoelectric Ceramics
Abstract:High-temperature bismuth-layered piezoelectric ceramics (CaxSr1−x)Bi4Ti4O15 have been prepared by the conventional solid reaction method. Our results reveal that there is a “phase transition induced by the composition” taking place in the solid solution at around x=0.4. During transition, the crystal structure changes from orthorhombic to pseudo-tetragonal and then back to orthorhombic. Although all (CaxSr1−x)Bi4Ti4O15 (with any x value) undergo a second-order ferroelectric-to-ferroelectric phase transition at about 200°C below their Curie temperature, only the ceramic with x=0.4 exhibits a failure in piezoelectric properties during the transition. It is suggested that, on the basis of the X-ray photoelectron spectroscopy results, this material failure is induced by the high concentration of oxygen vacancies in the material during the phase transition.
Document Type: Research Article
Affiliations: 1: The State Key Lab of High Performance Ceramics and Superfine Microstructures, Shanghai Institute of Ceramics, Chinese Academy of Science, Shanghai 200050, China 2: Department of Applied Physics and Materials Research Centre, The Hong Kong Polytechnic University, Kowloon, Hong Kong, China
Publication date: 2006-04-01