The effect of Sm 2O 3 dopant on the sintering characteristics and dielectric properties of barium zirconium titanate ceramics (BaZr x Ti 1- x O 3) was investigated. It is shown that trace amount of Sm 2O 3 can greatly affect the grain growth and densification of barium zirconium titanate ceramics during sintering. At the same time, the dielectric peak at high temperature shifts to lower temperature and that at low temperature shifts to higher temperature. The two dielectric peaks overlap with each other when the Sm 2O 3 dopant content varies from 0 25% to 1%, and the maximum relative dielectric constant is greatly enhanced. These effects may be attributed to the substitution actions of the rare earth element in perovskite lattice. At the doping content of 0 75%, the dielectric constant maximum of 23570 can be obtained. By adopting some proper additives, an excellent Y5V dielective material is obtained, and the room temperature properties are as follows: relative dielectric constant ε RT ≥23,000, dielectric loss tgδ≤0 0075 and the breakdown strength under alternating field E b≥5 kV·mm -1 .
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