Study On The Dielectric Properties Of Low-temperature Sintered Ba(Mg_1/3Ta_2/3)O₃ Microwave Ceramics

The development of modern technology accomplished the development of medium material. Ceramic is a important part of the medium material. In this paper, the application on the medium filter and the medium antenna of medium material was introduced first, then a method of low-temperature sinter aim at a material of good capability.The ceramic Ba(Mg_1/3Ta_2/3)O₃ (BMT) was known as one of the compound having the A( B1′/3B2′′/3)O3(A=Ba, Sr; B′=Mg, Zn; B′′=Nb, Ta) complex perovskite structure. It was the most excellent representative of the lowεr microwave dielectric ceramic materials, which can be developed as filters and resonators using in the microwave frequency area. But the sintering temperature of BMT was too high to about 1600℃, it can easily induce the volatilization of the Mg, Ta component and then deteriorate the dielectric properties. Therefore it is necessary to study on the BMT ceramic material with the propose to lower the sintering temperature and improve the dielectric properties.For the addition of BaSnO3 on (1-x)Ba(Mg_1/3Ta_2/3)O₃-xBaSnO3 ceramic, B-site Sn4+ ions substituted for Mg2+ or Ta5+ ions. It was found that the sinterability of BMT ceramic could be greatly improved by the addition of BaSnO3. The BMT ceramic could be obtained by the addition of 0.15% BaSnO3 sintered at 1500℃for 3h. While the microwave dielectric properties were sensitively related with the density of the ceramics, the excellent properties were as follow:εr=24.9,tgδ=7.3×10-4,Ï„f≈0.Then we research for the further depress the sinter temperature of the system. We use the glass of Bi2O3,and finally the temperature down to 850℃,and the capability kept well. For additional, we also research the addition of glass of ZnO, and also get a ideal result.