THE SINTERING BEHAVIOUR, MICROSTRUCTURE AND MICROWAVE DIELECTRIC PROPERTIES OF Li2Zn3Ti4O12 CERAMICS DOPED BY LiF

Li2Zn3Ti4O12 ceramics were prepared by the traditional solid-state reaction method. The sintering behaviour, microstructure and microwave dielectric properties of the LiF doped Li2Zn3Ti4O12 ceramics were studied by X-ray powder diffraction (XRD), Scanning Electron Microscopy (SEM) and a network analyser. When a small amount of LiF is added, LiF is a pure phase and the LiF and the Li2Zn3Ti4O12 phase coexisted under co-firing conditions, which reduced the sintering temperature to 900 degrees C without weakening its microwave dielectric properties. With an increase in the LiF content, the apparent density increased from 3.81 g.cm(-3) to 4.17 g.cm(-3), the dielectric constant decreased from 17.9 to 16.4, and the Q x f value firstly increased from 2800 GHz to 47 983 GHz and then decreased to 24 944 GHz. The temperature coefficient of the resonant frequency was slightly decreased from -48 ppm/degrees C to -54 ppm/degrees C. Excellent combined microwave dielectric properties were obtained for the LiF-added composition with x = 1 wt. % with an epsilon r of 17.9, a Q x f of 47983 GHz and a tau f of -48.3 ppm/degrees C when sintered at 900 degrees C for 4 h.