Prospection of (Pb,Ca)TiO3 morphotropic phase boundary from experimental thermal analysis data

摘要

Thermal expansion features of the (1-x)PbTiO3-xCaTiO3 (PCT) ceramics were experimentally investigated in a wide temperature range (150-900K). Distinct anomalies of the thermal expansion coefficient were observed in all compositions. Typical negative thermal expansion behavior of the displacive ferroelectric lead titanate system still remained for calcium concentrations up to ~42.5mol%. Additionally, the temperatures of nonpolar-nonpolar, nonpolar-polar and polar-polar phase transitions were found to be in agreement with those expected for a morphotropic phase boundary region earlier proposed in the literature for the PCT system.