Abstract
Low‐temperature phase relations in (Pb,La)Zr0.65Ti0.35O3 ceramics were determined as a function of La content and temperature. Dielectric and piezoelectric measurements and X‐ray data were used to locate and identify phase transitions. The FE1‐FE2 transition between rhombohedral ferroelectric phases occurs at higher temperatures as the La eontent is increased. For x>4, where x is the atom % La substituted for Pb, a phase region exists between the paraelectric and ferroelectric states. Dielectric data suggest that this region is antiferroelectric. For 6<xx∼8 exhibits unusual mechanical properties.