掺钙铬酸镧-氧化物复合材料的导电性能研究  

Conductivity of Ca-doped LaCrO_(3)-Oxide Composite

作　　者：齐素慈[1] 李建朝[1] 许继芳 QI Su-ci;LI Jian-chao;XU Ji-fang(Department of Material Engineering,Hebei College of Industry and Technology,Shijiazhuang 050091,Hebei,China;School of Iron and Steel,Soochow University,Suzhou 215137,Jiangsu,China)

机构地区：[1]河北工业职业技术学院材料工程系,河北石家庄050091 [2]苏州大学沙钢钢铁学院,江苏苏州215137

出　　处：《矿冶工程》2021年第4期125-129,共5页Mining and Metallurgical Engineering

基　　金：国家自然科学基金(51704201);河北省高等学校科学研究计划青年基金(QN2020161);河北工业职业技术学院自然科学项目(ZRY2017001)。

摘　　要：基于通用有效介质方程,建立掺钙铬酸镧-氧化物复合材料的电导率模型,研究服役温度、掺钙量、环境气氛和氧化物类型对电导率的影响。结果表明,掺钙LaCrO_(3)-ZrO_(2)中ZrO_(2)的临界体积分数为10%,临界指数为1.71;掺钙LaCrO_(3)-Al_(2)O_(3)中Al_(2)O_(3)的临界体积分数为15%,临界指数为1.74。当氧化物体积分数小于临界体积分数时,复合材料电导率随温度升高而逐渐减小;当氧化物体积分数远大于临界体积分数时,复合材料电导率随温度升高而急剧增大。复合材料电导率随掺钙量增加而逐渐提高,较低温度下氢气气氛中复合材料电导率明显低于在空气气氛中的电导率。掺钙铬酸镧中分别添加ZrO_(2)和Al_(2)O_(3)对导电性能的影响相差不大。A conductivity calculation model for the Ca-doped LaCrO_(3)-oxide composite was established based on a general effective medium equation,and used to investigate the effects of service temperature,Ca-doped content,atmosphere and oxide type on the conductivity of composite.The results show that the critical volume fraction(that is percolation threshold)of the ZrO_(2) for the conductivity of Ca-doped LaCrO_(3)-ZrO_(2) composite is 10%and the critical exponent is 1.71;while the percolation threshold of the Al_(2)O_(3) for the conductivity of Ca-doped LaCrO_(3)-Al_(2)O_(3) composite is 15%and the critical exponent is 1.74.When the volume fraction of the oxides is less than the critical volume fraction,the conductivity of the composite gradually decreases with the increase of temperature;when the volume fraction of oxides is much greater than the critical volume fraction,the conductivity increases sharply with the increase of temperature.The conductivity of composite increases gradually with the increasing of the Ca doping amount,and the conductivity of the composite in H2 atmosphere at a lower temperature is significantly lower than that in air atmosphere.It is shown that the doping of ZrO_(2) or Al_(2)O_(3) has brought little effect to the conductivity of the composite.

关 键 词：陶瓷复合材料 掺钙铬酸镧 电导率模型 氧化物 服役温度 环境气氛 

分 类 号：TG113.22[金属学及工艺—物理冶金]