Microstructural Characteristics and Nonequilibrium Core-Shell Phase in (Pb_xSr_(1-x))TiO_3 Materials and their Electrical Properties

摘要

Microstructural characteristics and the corresponding resistivity-temperature (#rho#-T) properties of microwave- and conventionalsintered Pb_(0.6)Sr_(0.4)TiO_3 materials with positive temperature coefficient of resistivity (PTCR) were investigated in the present work. The specimens pre-pared by microwave sintering exhibited a single T_c, whereas those prepared using conven-tional sintering show double T_c behavior. During the microstructural investigations, sintering aids, SiO_2 and TiO_2, showed intriguing liquid phase sintering characteristics in the speci-mens. Large amounts of Ph-species dissolved in high Si regions, where a nonequilibrium core-shell structure was frequently observed, especially for microwave sintered specimens, which showed very complicated domain arrangements in the grain interiors.