摘要
为了提高铝电解惰性阳极材料的性能,尝试在合成铁酸镍陶瓷阳极的过程中掺杂一定量MnO2.采用高温固相反应法在1200℃下烧结6h,制备了掺杂MnO2的铁酸镍阳极材料.对掺杂试样进行X射线衍射分析,并且研究了掺杂MnO2对材料密度、导电性及抗弯强度和抗热震性的影响.研究结果表明,掺杂MnO2后未形成新相,MnO2与NiFe2O4形成固溶体,Mn4+离子取代了部分Fe3+离子,材料仍是镍铁尖晶石结构;掺杂MnO2后,NiFe2O4的晶格产生畸变,说明MnO2促进了烧结,提高了材料的密度;并且由于Mn4+离子取代Fe3+离子,产生阳离子空位,改善了铁酸镍阳极的导电性.同时MnO2对改善试样的抗弯强度及抗热震性也有明显作用.
In order to improve the properties of nickel ferrite ceramic as inert anode in aluminium electrolysis, MnO2 as additive was doped in NiFe2O4 spinel. The nickel ferrite ceramic with MnO2 was made by solid-phase reaction at 1200 ℃ for 6 h. XRD analysis showed that when MnO2 was added, no new phase existed, and MnO2 and NiFe2O4 formed solid solution; Mn^4＋ replaced part of Fe^3＋ and the resulting sample still had the structure of NiFe2O4 spinel. The effect of MnO2 addition on the density, conductivity, thermal shock resistance and bending strength of the samples was also studied. The results showed that Mn^4＋ replacing part of Fe^3＋ caused the crystal lattice of NiFe2O4 spinel to become aberrated, which could promote sintering and improved the density. Because Mn^4＋ replaced part of Fe^3＋ and produced conduction electrons, the conductivity of the sample was improved; thermal shock resistance and bending strength were also promoted.
出处
《过程工程学报》
EI
CAS
CSCD
北大核心
2006年第3期495-498,共4页
The Chinese Journal of Process Engineering
基金
国家重点基础研究规划资助项目(编号:G1999064903)
国家'863'高技术资助项目(编号:2001AA335010)
关键词
铁酸镍
惰性阳极
掺杂
密度
电导率
抗弯强度
抗热震性
nickel ferrite
inert anode
additive
density
conductivity
bending strength
thermal shock resistance
