Structural and Electrical Properties of Ba0.85Ca0.15Hf0.1Ti0.9O3 Ceramics

DI LORETTO, ARIEL; FRATTINI, AGUSTÍN; MACHADO, RODRIGO; DE SANCTIS, OSCAR; M. G. STACHIOTTI

Porto

Congreso; 13th European Meeting on Ferroelectricity; 2015

here is an urgent demand for high performance Pb-free piezoelectrics to substitute for the current PZT family. A triple point type morphotropic phase boundary in xBa(Zr0.2Ti0.8)O3-(1-x)(Ba0.7Ca0.3)TiO3 systemhas been reported that shows equally as excellent piezoelectricity as soft PZT at room temperature 1. Those ceramics have attracted great attention during the last years due to their excellent piezoelectric properties,particularly for the composition x = 0.5: Ba 0.85Ca0.15Zr 0.1Ti0.9O3 (BCZT). BCZT ceramics have however some critical problems such as high processing temperatures and low Curie temperature. In this work weinvestigate the effects of the replacement of Zr ions by Hf. Although the chemical properties of hafnium is very much similar to that of zirconium, its atomic weight (178.5 g/mol) is much larger than that of Zr (91.2g/mol). Ba0.85Ca0.15Hf0.1Ti0.9O3 (BCHT) ceramics were prepared by a high-energy ball milling process, and their structural and electrical properties were compared with that of BCZT samples prepared under thesame conditions.