Materials Chemistry and Physics, Vol.170, 118-122, 2016
Microwave dielectric properties of low-fired (1-x) Mg2Si0.9V0.1O4-xCa(0.8)Sr(0.2)TiO(3) composite ceramics.
The low-fired (1-x)Mg2Si0.9V0.1O4-xCa(0.8)Sr(0.2)TiO(3) (MSV-CST, 0.15 <= x <= 0.25) composite ceramics doped with 4 wt% LiF were fabricated by a conventional solid-state route, and their sintering characteristics, microstructures, crystal compositions and microwave dielectric properties were investigated systematically. Eutectic liquid phase Ca2V2O7 and LiF were developed, which lowered the sintering temperature of MSV-CST composite ceramics to 900 degrees C. The microwave dielectric properties of MSV-CST ceramics were mainly controlled by the CST composition (x). A typical sample of 0.81MSV-0.19CST-4 LiF, which owned well microwave dielectric properties (epsilon(r) = 11, Q x f = 49 000 GHz (at 9.5 GHz), and tau(f) = -7 ppm/degrees C), were achieved at 900 degrees C for 4 h. Such sample was compatible with Ag electrodes, suitable for the low-temperature co-fired ceramics (LTCC) applications. (C) 2015 Elsevier B.V. All rights reserved.