Effects of sintering condition on microstructure and microwave dielectric properties of Ba(Mg1/3Ta2/3)O3 ceramics

The effects of sintering condition on the microwave dielectric properties and the microstructure of Ba(M1/3Ta2/3)O-3 ceramics were investigated. Does not only the amount and types of the Ba-Ta-O extra phase but also the degree of the B-site ions ordering change with the sintering conditions, so that the dielectric properties change a lot. The B-site ions can be arranged more in order by annealing process of slowly cooling, and the Q value improved at the same time. However, it has been found that the longer the sintering time or the higher the sintering temperature, the more the amount and types of the extra phase appeared, which would cause the dielectric loss increase. When the Ba(Ma(1/3)Ta(2/3))O-3 ceramics was sintered at 1600 degreesC for two hours then annealed to 1000 degreesC with the cooling rate of 50 degreesC per hour, its Q value could reach 15000 (10 GHz), which has been used in millimetre-wave band as resonator material and works well.