| The preparation method, dielectric properties of Bi2O3-ZnO-Nb2O3(BZN) ceramic system, and the effect of TiO2 dopants on the system were studied in this paper.BiNbO4 based dielectric ceramics were studied first. It has good sintering behaviour, but the high dielectric loss and nagetive temperature coefficient make it not suitable for application. The way of B-site substitution of Ta for Nb was also studied, which makes the sintering temperature increasing and dielectric properties getting better.Different processing route of BZN system were also studied. The results show that BZN ceramic with good dielectric properties can be got using (Nb2O5-ZnO) precursor. While using (Bi2O3-Nb2O5) precursor or calcinating Bi2O3, ZnO, Nb2O5 directly can hardly get BZN ceramic with good dielectric properties. The best dielectric properties can be obtained when calcinating (Nb2O5-ZnO) precursor at 860℃for 2 hours. Fast heating can benefit for the dielectric properties during the sintering of BZN ceramic. The dielectric properties can be listed as follows:ε>=150 tgδ<=2×10-4αε<=-370×10-6/℃On the basis of experiments above, through doping of TiO2, the sintering temperature of BZN-based system can be lowered from 1100℃to 900℃, and temperature coefficient of the ceramic shifts for the positive direction from -370×10-6/℃to 200×10-6/℃.
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