Preparation and Characterization of Semi-Conducting (Ba,Sr)TiO3 Powders by a Wet Chemical Route
Ultrafine (Ba,Sr)TiO3-based powders used for making positive temperature coefficient of resistance (PTCR) were synthesized by two chemical steps: polyacrylamide gel process and liquid phase coating process. First, donor doped (Ba,Sr)TiO3 powders were synthesized by polyacrylamide gel process at rather low temperature, and the physical and chemical characteristics of the gels and the precursorpowders were investigated by DSC, TG, XRD and TEM. Secondly, acceptor and sintering aid were coated by an aqueous solution containing acceptor (Mn) and additive (Si). The characterization and sintering behavior of the semi-conducting powders and the PTC effect of ceramic samples prepared by the as-obtained powders were investigated.
Wei Pan, Jianghong Gong, Chang-Chun Ge and Jing-Feng Li
Z. P. Zheng et al., "Preparation and Characterization of Semi-Conducting (Ba,Sr)TiO3 Powders by a Wet Chemical Route", Key Engineering Materials, Vols. 280-283, pp. 657-660, 2005