Technology and electrophysical properties of piezoelectric ceramics based on PbTiO ₃ – Ba 0.85 Ca 0.15 Ti 0.90 Zr 0.10 O ₃ solid solution

The aim of the research is to develop a technology of ceramic piezoelectric materials which сan be used in thermo cyclic mode at temperatures above 280 °C. This technology has been developed for the piezoelectric ceramics based on (1-x)PbTiO3 – xBa0.85Ca0.15Ti0.90Zr0.10O3 (x = 0.15–0.45). The use of low-temperature (380–400 °C) synthesis of ultrafine phase powders and stepwise firing of press blanks make it possible to produce densely packed ceramics with grain diameter of 1 to 2 µm. It has been established that the mole fraction of Ba0.85Ca0.15Ti0.90Zr0.10O3 in the composition increases εТ33/ε0 from 620 to 1070, and increases d33 from 165 to 330 pC/N. Thermal cycling of piezoelements based on phases with x = 0.2–0.25 (8 cycles: heating to 350 °C – cooling) reduces d33 only by 6–8%, and εТ33/ε0 – by about 5%.