Bismuth layer-structured piezoelectric ceramics with high piezoelectric constant and high temperature stability

Abstract

Bismuth layer structured lead free piezoelectric ceramics in the system Sr1−x Ca x Na0.5Bi4.5Ti5O18 + 1 wt% CeO2 (SC x NBTC; x = 0, 0.25, 0.5, 0.75 and 1) have been prepared through the conventional solid-state reaction method. X-ray diffraction measurement indicates that a single phase layered perovskite was obtained for all compositions, and with the increase of x, the lattice parameter of c/a value have been increased first and then decreased, giving maximum values of c/a = 12.7085 when x = 0.5. At x = 0.25, the SC x NBTC ceramics exhibited the best properties with a large piezoelectric constant d 33 of 31 pC/N and a high Curie temperature of 607 °C. Moreover, SC x NBTC ceramics have outstanding temperature stability and piezoelectric. The SC0.25NBTC ceramics showed high piezoelectric constant d 33 value (31 pC/N) and good stability with no change of d 33 values after annealing at 350 °C. The results indicate that these compounds are very promising piezoelectric materials for high-temperature transducer applications at 350 °C.