| In this paper, we first studied the dielectric properties of MgTiO3, the emphasis is on the relation of dielectric properties and the structure of MgTiO3. Adding small amount of Co2+ to MgTiO3,we got the (Mg0.95Co0.05) TiO3 system, which has good dielectric properties. The temperature coefficient of dielectric constant of (Mg0.95Co0.05) TiO3 system is 54ppm/℃,which is too big to be used in microwave devices. In order to adjust it to near zero, we added CaTiO3, which has a large negative temperature coefficient of dielectric constant to the systems. At the same time, we adjusted the technology process, which improved the sintering outcome and dielectric properties of (Mg0.95Co0.05) TiO3. The influence of calcination and sintering on the dielectric properties was also studied in the paper. Through the experiments, we found the sintering temperature in which the best dielectric properties occurred and we got (Mg0.95Co0.05) TiO3- CaTiO3 with good dielectric properties. We also found that, in the calcinations temperature near 1100℃, the increase of calcination temperature has little influence on the dielectric properties . We also added a kind of glass to the system as the flux, which formed liquid phase in the sintering process, accelerated the sintering of (Mg0.95Co0.05) TiO3- CaTiO3 ceramics. When the amount of glass added to the system is proper, (Mg0.95Co0.05) TiO3- CaTiO3 systems exhibited the best dielectric properties. On the basis of experiments, we have finally achieved high quality, and zero temperature coefficient microwave ceramics with superior dielectric properties. Its main parameters were as follows: ( = 20 ( 2, (c = 0 ( 30ppm/℃, tan( ( 1( 10(4...
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