Effects of Doping on Sintering Process and Dielectric Properties of PMN Ceramics

Sintering process and dielectric properties were studied by adding a small amount of different dopants into PMN ceramics using normal two-step method. When doped with lmol% Li2O, the sintering temperature of PMN can be reduced to 950-1000℃ . The dielectric constant and loss tangent of this material are 13500 and 0.55% respectively, which are better than those of pure PMN. When doped with 2mol% SrO, low temperature sintering about 800-900 ℃ can be attained while its loss tangent at room temperature reduced to only 0.36%. Analysis results show that the materials have good microstructures and are highly condensed. Anyhow, doped with Li2O and SrO can slightly lower and enhance the extent of diffuse phase transition (DPT).