Papers by Author: Shao Bo Qu

Abstract: To improve the temperature stability of PMN(Pb(Mg_1/3Nb_2/3)O₃)-based ceramics, PMN-based composite ceramics were prepared by co-sintering two kinds of ceramics with different curie temperature. One unit is MHT(0.82PMN (Pb (Mg_1/3Nb_2/3) O₃) -0.18PT (PbTiO₃) (the curie temperature Tm=74°C)), and the other unit is MLT (0.88PMN (Pb (Mg_1/3Nb_2/3) O₃)-0.12BT (BaTiO₃) (the curie temperature Tm=-50°C)). The effects of the sintering temperature and the ratio of high and low T_m units on dielectric temperature stability were studied. The results show that the temperature stability can be improved greatly by co-sintering and coating method. The results show that PMN(Pb(Mg_1/3Nb_2/3)O₃)-based composite ceramics are promising candidate for practical applications.

Abstract: 0.85Pb(Zn1/3Nb2/3)O3-0.10BaTiO3-0.05PbTiO3 (abbreviated as PZN-based ceramics hereafter) ternary system ceramics with Zn2+ deficiency were synthesized by the columbite method. The effect of deficient Zn2+ on phase structure, ordered micro-region size and dielectric properties was investigated in detail. The analysis of Raman scattering spectra demonstrated that Zn2+ deficiency sharply enlarged the ordered micro-region size. Zn2+ deficiency significantly increased the dielectric constant, and decreased the diffusion degree of phase transition. There is a close correlation between effective ordered micro-regions size and dielectric properties for the PZN-based ceramics.