Preparation and Study of 0.7(Mg_(0.8)Zn_(0.2))TiO_3·0.3{Ba_4Nd_(28/3)Ti_(18)O_(54)·zBi_2O_3} Microwave Dielectric Ceramics

摘要

The (Mg_(0.8)Zn_(0.2))TiO_3(MZT) as the foundation is mainly studied to join high dielectric material Ba_4Nd_(28/3)Ti_(18)O_(54)·zBi_2O_3(BNT) to preparation microwave dielectric ceramic 0.7(Mg_(0.8)Zn_(0.2))TiO_3·0.3{Ba_4Nd_(28/3)Ti_(18)O_(54)·zBi_2O_3}(z=0.15, 0.18, 0.2) to improve dielectric properties of MZT. While Bi~(3+) could reduce the sintering temperature to make MZT and BNT composite in a lower sintering temperature (1200～1230°C). According to the results of the dielectric properties, density, XRD and SEM tests of the obtained ceramics, we can find out that the amount of doped Bi~(3+) and the sintering temperature affected the structure and properties of the ceramics. The results show that when z=0.18, 0.7(Mg_(0.8)Zn_(0.2))TiO_3·0.3{Ba_4Nd_(28/3)Ti_(18)O_(54)·zBi_2O_3} sintering at 1230°C can get good dielectric properties: ε_r =35.56, Q_f =5811GHz, τ_t =-3.225 ppm/°C.