Microwave dielectric properties of (Pb0.4Ca0.6)(Fe0.5Ta0.5)O3 ceramics prepared by mechanochemical processing

The complex perovskite (Pb0.4Ca0.6)(Fe0.5Ta0.5)O3 ceramics (PCFT) were prepared by mechanochemical process and the microwave dielectric properties were investigated. A single phase PCFT of the perovskite structure was obtained with PbO, CaCO3 and pre-reacted FeTaO4 by high-energy mechanochemical milling and subsequent heat treatment. Without calcination, a single phase of the perovskite structure could be obtained by 60 h milling and sintering at 1000NBDGC for 3 h, which was lower by 100NBDGC than that prepared by conventional mixed oxide method. The PCFT specimen sintered at 1050NBDGC for 3 h showed dielectric constant of 62, QDTf of 9000, and the temperature coefficient of resonant frequency (TCF) of -15 ppm/DGC.