Influence of sintering temperature on nonlinear electrical behavior anddielectric properties of TiO_2-based varistor ceramics

Based on the single sintering process,five disk samples of(Sr,Bi,Si,Ta)-doped TiO_2-based varistor ceramics were fabricated,by sintering separately at the temperatures of 1200 to 1400 ℃ for 2.5h.The influence of sintering temperature on the nonlinear electrical behavior and dielectric properties of these samples were investigated by measuring the characteristics of J-V,dielectric constant,dielectric loss and nonlinear coefficient.It was found that,between 1200 and 1400℃,both breakdown electrical field and nonlinear coefficient decreased and dielectric constant increased gradually with decreasing sintering temperature.It is suggested that the sintering temperature should be about 1350℃ considering both nonlinear electrical behavior and dielectric properties of TiO_2-based varistor ceramics.