The Effect of Sintering Temperature on Lead-Free Bi_(0.5) (Na_(0.78)K_(0.22))_(0.5)TiO_3-(Na_(0.5)K_(0.5))NbO_3 Ceramics

摘要

Lead-free piezoelectric Bi_(0.5)(Na_(0.78)K_(0.22))_(0.5)TiO_3-(Na_(0.5)K_(0.5))NbO_3 ceramics have been synthesized by a conventional solid-state reaction methods at different sintering temperatures (1100-1200℃). The effect of sintering temperature on the crystal structure, density and electrical properties was investigated. The Bi_(0.5)(Na_(0.78)K_(0.22))_(0.5)TiO_3-(Na_(0.5)K_(0.5))NbO_3 ceramics sintered at an optimum temperature of 1150℃ exhibited high density and electrical properties. High field-induced strain (0.22%) and high dynamic piezoelectric coefficient (S_(max)/E_(max) = d~*_(33) = 440 pm/V) were obtained for samples sintered at 1150℃. These results are believed to be due to the high density and lower conductivities at this temperature.