TiO2 ceramics doped with 0.75 mol% Ca and 2.5 mol% Ta were sintered at different temperatures ranging from 1300 to 1450degreesC. The effects of sintering temperature on the microstructure, nonlinear electrical behavior, and dielectric properties of the ceramics were studied. The sample sintered at 1300degreesC exhibits the highest nonlinear coefficient (5.5) and a comparatively lower relative dielectric constant. (C) 2002 Elsevier Science Ltd. All rights reserved.