Papers by Author: Mi Xiao

Abstract: The effects of BaB₂O₄ glass on the synthesis of Ba₂Ti₉O₂₀ were studied. The doping amounts of BaB₂O₄ varied from 0 to 10wt% and the compositions were sintered in the temperature range of 1200~1280^◦C for 2h. The benefit of BaB₂O₄ addition to the densification of the ceramics is apparently due to the liquid phase which accelerates the migration of reactant species, which results in the decreasing of the sintering temperature. With the amount of BaB₂O₄ increased, the microstructure and properties of the ceramics were also changed: BaTi₄O₉ became the major phase instead of Ba₂Ti₉O₂₀, bulk density decreased, and dielectric constant decreased accordingly, while dielectric loss kept small.

Abstract: (Ag1-xNax)(Nb1-yTay)O3 (ANNT) dielectric ceramic material with perovskite structure was prepared through a wet chemical synthetic method. The precursor solution for the material was obtained from the citric acid solutions of different metal oxides or nitrates with exact molar ratio by a sol-process. The precursor solution thus prepared was then heated under an infrared lamp to evaporate the solvent. This period showed a self-propagating combustion behavior. Ceramic powder was obtained after the residue was calcined at a certain temperature. It is proved that ANNT sintered at 1040°C was finely grained. The obtained ceramic showed excellent high frequency dielectric properties with considerable high dielectric constant and rather low dissipation factor under 1MHz.