Preparation and characterisation of the Ba(Zr,Ti)O-3 ceramics with relaxor properties

Ba(Zr-x Ti1-x)O-3 ceramics with x = 0. 10, 0. 15 and 0. 18 were prepared via solid state reaction. For the composition x = 0. 10, ceramics with various Min sizes in the range 0.75-3.20 mu m were obtained by sintering at various temperatures 1350-1500 degrees C. High permittivity (above 14,000 at the transition temperature) and losses smaller than 7% for temperatures below 120 degrees C, together with a shift of the Curie temperature towards lower values with increasing x. are characteristic to these ceramics. A ferroelectric-relaxor crossover takes place when x increases, with intermediate character for all the compositions. For the composition x = 0. 10, the relaxor state is favoured by reducing the grain size. (c) 2007 Elsevier Ltd. All rights reserved.