Dielectric Tunable Properties of Ba_0.4Sr_0.6TiO₃-Mg₂SiO₄ Microwave Composite Ceramics

Abstract

(1−x)Ba_0.4Sr _0.6 TiO₃(BST)–xMg₂SiO₄(MS) (x = 0.00, 0.05, 0.10, 0.20, 0.40, 0.50 and 0.60) composite ceramics have been prepared by the traditional solid state reaction, and its structural and dielectric properties have been characterized. Only two phases, corresponding to the BST and MS phases, are clearly visible for x ≥ 0.20. The permittivity is tailored from 763 to 75 by manipulating the addition of MS from 5 wt% to 60 wt% and the tunability decreases from 11.2% to 6.4% measured at 10 kHz. Meanwhile, the Q value of composite ceramics is decreased from 351 to 128.

Keywords:

• Tunability
• Microwave dielectric properties
• Composite ceramics

Acknowledgments

This research was supported by the Ministry of Sciences and Technology of China through 973-project under grant 2009CB623302, the Cultivation Fund of the Key Scientific and Technical Innovation Project, Ministry of Education of China (No.707024), Shanghai Committee of Science and Technology (No. 07DZ22302).