Thermal expansion of ceramics in Pb(Zn _{1 3}Nb _{2 3})O₃ - based solid solution systems

No systematic study on the thermal expansion behavior of Pb(Zn _{1 3}Nb _{2 3})O₃ - based ceramics has been made so far. This study is very important because these materials are potential candidates for multilayer capacitors and optical-mirrors substrates.Lead-zinc-niobate Pb(Zn _{1 3}Nb _{2 3})O₃ (PZN) based ceramics with perovskite structure are difficult to synthesize because of the formation of a undesirable pyrochlore phase. However, an addition of BaTiO₃, PbTiO₃ or SrTiO₃ stabilizes perovskite structure in PZN. In this work ceramic samples in the solid solution systems of PZN with these additives were prepared and thermal expansion measurements were carried out on the ceramic specimens using a push rod dilatometer. No substantial and systematic change in bulk thermal expansion with the change in composition was observed. Most of the samples demonstrated very low thermal expansion at lower temperature.