Relaxor behavior of piezoelectric Pb(Yb_(1/2)Nb_(1/2))O_3-PbTiO_3 ceramics sintered at low temperature

摘要

A (100-x)Pb(Yb_(1/2)Nb_(1/2))O_3-xPbTiO_3 [PYN-PTx] solid solution system with 49.0≤x≤51.0 was prepared using a conventional ceramics process and sintered at low temperature. When excess PbO was added into the PYN-PTx system, all samples were sintered at temperatures as low as 800℃ with good dielectric and piezoelectric properties. It is suggested that a liquid phase with excess PbO was formed during the sintering and improved the densification of PYN-PTx ceramics at low temperatures. For the PYN-PTx binary system, it was found that the temperature dependence of the relative permittivity follows a Curie-Weiss Law above the deviation temperature (T_D) at high temperatures. Good piezoelectric properties of d_(33)= 510 pC/N, ε_r=2800 at RT, k_p=0.57, and k_t=0.42 with T_c= 373℃ were obtained for PYN-PT49.5 ceramics sintered at 800℃ for 8 h.