Papers by Author: Xiao Hui Wang

Abstract: Sintering behavior of pure and Nb-doped barium titanate powders prepared by high-gravity reactive precipitation (HGRP) process was investigated. A thermal dilatometer was employed to monitor the sintering shrinkage continuously during sintering. TEM and SEM were used to characterize the microstructures of the samples. The experimental results confirmed that Nb-doped BaTiO3 ceramics sintered at 1220°C for 2 h reached a larger densification of 97.0% relative density compared with 94.6% of pure BaTiO3 ceramics sintered at 1265°C for 2 h, and Nb-doped BaTiO3 ceramics had a smaller grain size (1.2μm) than that of pure BaTiO3 ceramics (2μm).

Abstract: Sintering behavior and mechanism of barium titanate powders prepared by high-gravity reactive precipitation (HGRP) process has been investigated by a dilatometer. The mean particle size of barium titanate powders prepared by HGRP was about 80 nm. Pure BaTiO3 pellets were sintered at a constant heating rate of 2.0 K/min and the temperature of shrinkage-onset for pellet was 1060°C. The maximal shrinkage was 165um and the maximum of shrinkage rate was 8.0 x 10-3 / min at 1170°C. The sintering mechanism for the initial stages of sintering was determined by isothermal dilatometric measurements and was found to be viscous flow.