Influence of Compositional Variation on the Electrical Properties of [Pb(ZnNb)O]-[Pb(Zr,Ti)O] Ceramics and Their Transducer Application.

The ternary system of x[Pb(ZnNbO. ( )[Pb(ZrTi)O] composition with " " varying from 0.1 to 0.6 with interval of 0.1 and " " varying from 0.46 to 0.52 with interval of 0.01 was studied. The main objective was to maximize the dielectric and electromechanical properties through compositional variation and then to establish the full property matrix of the optimized composition for further analysis and device applications. Ceramics with pure perovskite phase have been produced in the entire compositional range that was investigated. The highest ferroelectric and electromechanical properties were obtained at the 0.4[Pb(ZnNb)O-0.6[Pb(ZrTi)O]-(0.4 PZN-0.6 PZT) composition with remanent polarization ( ) of /cm, piezoelectric charge coefficient (d) of 465 pC/N, and electromechanical coupling coefficients ( , , and ) of 0.67, 0.52, and 0.77, respectively. Full property matrix for 0.4 PZN-0.6 PZT was obtained and was used as input in the finite-elements analysis of ceramics in disc and hemispherical shell form. Hollow spherical omnidirectional transducers were fabricated from the lead zinc niobate-lead zirconate titanate (PZN-PZT) ceramics as a device prototype, and underwater characteristics have been determined and reported for these transducers.