Preliminary testing of NiFe2O4-NiO as ceramic matrix of cermet inert anode in aluminum electrolysis
来源期刊：中国有色金属学报(英文版)2003年第5期
论文作者：秦庆伟 赖延清 肖劲 李劼 刘业翔
文章页码：1208 - 1212
Key words：NiFe2O4-NiO ceramic; solubility; electrical resistivity; inert anode; aluminum electrolysis
Abstract: Sintered samples of nickel ferrite-nickel oxide ceramic, usually used as the ceramic phase of cermet inert anode in aluminum electrolysis, were prepared and characterized. The solubilities of NiFe2O4-NiO ceramics were measured using an equilibration technique in the Na3AlF6-10%AlF3-5%CaF2-5 %Al2O3 melts at 960℃. Electrical resistivity was also measured for NiFe2O4-NiO ceramic samples prepared using the usual ceramic technique as function of temperature and content of NiO with an improved pyroconductivity test device, consisting of a specially constructed closed furnace and a Potentiostat/Galvanostat, based on the conventional direct current four-probe technique. Results show that, under the experimental conditions, the solubility of Fe from NiFe2O4 is 0.06% and Ni from NiFe2O4 is 0.008%. The solubility of Fe and Ni from NiFe2O4-NiO ceramic is inversely related to each other. The solubility of Ni increases but overall solubility of NiFe2O4-NiO ceramics decreases with increasing NiO content. The studied ceramic samples have a semiconductor behavior where electrical resistivity ρ decreases with increasing temperature and the resistivity ρ increases with increasing porosity. The resistivity ρ of NiFe2O4-NiO ceramic shows a minimum with increasing the content of NiO at various temperatures.
基金信息：the National Key Fundamental Research and Development Program of China
