A lead-reduced ferrolectric solid solution with high curie temperature: BiScO3-Pb(Zn1/3Nb2/3)O3-PbTiO3

A lead-reduced ternary ferroelectric solid solution system of BiScO3-Pb(Zn1/3Nb2/3)O3-PbTiO3 (BS-PZN-PT) in the form of the ceramic was investigated for its structure and properties in order to develop novel ferroelectric materials with high Curie temperature and good piezoelectric properties. A morphotropic phase boundary region was delimited in this system between rhombohedral and tetragonal phases. The Curie temperature TC of this ternary system varied from 321 °C to 131 °C and the coercive fields EC from 24.6 kV/cm to 8.62 kV/cm. The piezoelectric coefficient d33 varies in the range of 100-320 pC/N with increasing PZN content. Those compositions within the MPB region possess good comprehensive piezoelectric properties, for example, d33 and TC of compositions with 0.32BS-0.15PZN-0.53PT, 0.34BS-0.15PZN-0.51PT and 0.28BS-0.30PZN-0.42PT are 313 pC/N and 319 °C, 300 pC/N and 304 °C, 320 pC/N, and 236 °C, respectively. The high TC and d33 make it a promising material for high-powder ultrasound transducers for use over a wide temperature range.