Abstract
Investigations have been made on the hot-pressed ceramics of the solid solution xA(A1/3'Nb2/3)O3–(1-x)[(Pb(ZryTi1-y)O3], where A=Ba or Sr, A'=Pb, Ca or Sr. Curie temperatures, lattice constants, dielectric constants and electromechanical coupling coefficients have been determined as a function of x for various systems near the tetragonal-rhombohedral morphotropic phase boundary. Polished specimens in the compositional range 0.10<x<0.20 and 0.40<y<0.60 have been found to have high optical transmittance and to show pronounced electrooptic effects. The phase diagram of the system Ba(Sr1/3Nb2/3)O3–PbZrO3–PbTiO3 has been also studied and the existence of the intermediate phase, which is likely to be antiferroelectric, has been confirmed.