CaO掺杂10NiO-NiFe₂O₄复合陶瓷的导电性能

来源期刊：中国有色金属学报2006年第9期

论文作者：赖延清 张刚 张勇 李劼 贺跃辉 黄伯云 刘业翔

文章页码：1608 - 1614

关键词：10NiO-NiFe₂O₄; CaO; 导电性能; 惰性阳极; 铝电解

Key words：10NiO-NiFe₂O₄; CaO; electrical conductivity; inert anode; aluminum electrolysis

摘    要：研究添加剂CaO含量和烧结温度对CaO掺杂10NiO-NiFe₂O₄复合陶瓷的物相组成和电导率的影响。 结果表明： CaO含量在0~4%范围内， 烧结试样的X射线衍射谱仅有NiO和NiFe₂O₄的衍射峰； 10NiO-NiFe₂O₄复合陶瓷在空气中升温过程存在明显的吸氧和失氧行为； CaO含量对1 473 K烧结的10NiO-NiFe₂O₄复合陶瓷的电导率影响显著； 当CaO含量为0~1%时， 随测试温度的升高， 材料电导率逐渐增大， 随后在773~923 K出现1~2个数量级的突降， 然后重新缓慢增大； 当CaO含量为2%和4%(质量分数， 下同)时， 材料电导率在298~1 233 K范围内随着测试温度的升高而增大； 2%CaO掺杂10NiO-NiFe₂O₄复合陶瓷在不同测试温度下均具备最高电导率， 1 233 K下达到16.29 S/cm， 远高于未掺杂试样的1.03 S/cm； 烧结温度由1 473 K提高到1573 K时， 未掺杂试样在1 233 K时电导率提高近15倍， 2%CaO掺杂试样1 233 K时电导率略有提高。

Abstract: The effects of CaO content, in the range from 0% to 4%, and sintering temperature on the phase composition and electrical conductivity of CaO doped 10NiO-NiFe₂O₄ composite ceramics were studied. The results show that the composites consist of NiO phase and NiFe₂O₄ phase. There is an apparent oxygen absorbing and releasing behavior during the heating process in air for 10NiO-NiFe₂O₄ composites. The electrical conductivity of composites sintered at 1 473 K markedly depends on the CaO content. As the CaO content is in the range from 0% to 1%, the conductivity increases firstly with the temperature increasing from room temperature to 773 K, then abruptly decreases with one or two orders of magnitude at the temperature between 773 K and 923 K, and finally increases gently with the temperature increasing from 923 K to 1 233 K. As the CaO content is in the range from 2% to 4%, the conductivity increases with the temperature increasing without a decreasing phenomenon. The maximum conductivity of 16.29 S/cm at 1 233 K is obtained for composites doped with 2%CaO, compared to the 1.03 S/cm of the undoped composites. As the sintered temperature increases from 1 473 K to 1 573 K, the electrical conductivity at 1 233 K increases about 15 times for the undoped composites, compared to a slight increase for the 2%CaO doped composites.

基金信息：湖南省自然科学基金资助项目