Electrical and Electromechanical Properties of Hot-Pressed Pb(Fe_1/2Nb_1/2)O₃ Ferroelectric Ceramics

Abstract

Dense ceramics of Pb(Fe 1/2 Nb 1/2 )O 3 with high resistivity were fabricated below 1000°C by making use of the hot-pressing technique. For these hot-pressed specimens, measurements of the spontaneous polarization, dielectric constants, electromechanical coupling factors, piezoelectric constants and elastic compliance constants were carried out as a function of temperatures between -30°C and 200°C. Temperature variations of the resistivity and linear thermal expansion were also studied. At room temperature, the following values were obtained: ε 33 T /ε 0 =2640, P s =11.3 µC/cm 2 , k 33 =0.266, d 33 =145×10 -12 C/N and s 33 E =12.3×10 -12 m 2 /N. These values were briefly compared with those of BaTiO 3 ceramics.