Structure and dielectric properties of Ba1-xSrxCuSi2O6-Ba0.55Sr0.45TiO3 ferroelectric-dielectric composite ceramics

yBa(1-x)Sr(x)CuSi(2)O(6)-(1-y) Ba0.55Sr0.45TiO3 (x = 0, 0.2 and y = 10 wt%, 30 wt%) ferroelectric-dielectric composite ceramics were prepared by the solid-state sintering method. The relationship among phase composition, microstructures and dielectric properties has been investigated. By adjusting the content of the Ba1-xSrxCuSi2O6 and the content of Sr2+ in the Ba1-xSrxCuSi2O6, the effect of the dielectric material on BST was studied. With the increase of Ba1-xSrxCuSi2O6 content and the increase of the Sr2+ content, the dielectric peak of the composite material is gradually suppressed and broadened, and the Curie temperature (Tc) moves to the low temperature. The introduction of Ba1-xSrxCuSi2O6 reduced the permittivity of the composite material to a certain extent, at the same time, the dielectric tunability and quality factor (Q) value are maintained at a high level. The dielectric tunability of the four composite ceramics obtained is still higher than 10% under the applied electric field (at 30 kV/cm). The 30 wt% BCSO-70 wt% BST55 system and the 30 wt% BSCSO-70 wt% BST55 system has lower dielectric permittivity (830, 577), higher dielectric tunability (17.3%, 10.2% at 30 kV/cm) and a decent Q value (149 at 1.25 GHz, 168 at 1.31 GHz).

Automated summary

The relationship among phase composition, microstructures, and dielectric properties of different ceramic composites was investigated. It was found that increasing the content of Ba1-xSrxCuSi2O6 and Sr2+ gradually suppresses and broadens the dielectric peak of the composites. While introducing Ba1-xSrxCuSi2O6 reduces dielectric permittivity to some extent, dielectric tunability and quality factor remain high.