NiFe_2O_4-NiO复合陶瓷的熔盐腐蚀行为  

Molten salt corrosion behavior of NiFe_2O_4-NiO composite ceramics

作　　者：王昊[1] 周科朝[1] 李志友[1] 刘宝刚[1] 

机构地区：[1]中南大学粉末冶金国家重点实验室,长沙410083

出　　处：《粉末冶金材料科学与工程》2012年第2期263-269,共7页Materials Science and Engineering of Powder Metallurgy

基　　金：国家重点基础研究发展规划(973计划)资助项目(2005CB623703);国家高技术研究发展计划(863计划)资助项目(2008AA030501);国家自然科学基金创新团队项目(50721003)

摘　　要：采用气氛烧结技术制备NiFe2O4-xNiO复合陶瓷材料(x为复合陶瓷中NiO的质量分数,%。x=0、5、10、17、25),并以该材料作阳极进行960℃的铝电解实验。分析烧结体的显微结构和物相组成以及电解试样的表层形貌与成分,研究NiO的添加对NiFe2O4陶瓷烧结性能和电解腐蚀性能的影响,并对该材料的烧结机制和熔盐腐蚀行为进行探讨。结果表明:氮气气氛下1 300℃烧结的NiFe2O4-NiO复合陶瓷存在NiO和NiFe2O4两种物相,NiO相含量高于理论值;NiFe2O4陶瓷的相对密度为98.54%,添加NiO后复合陶瓷材料的相对密度有所下降,但仍保持在95%以上;电解过程中阳极表面形成不含NiO相的致密保护层,阻止电解质熔盐的渗透;保护层厚50～80μm,为含Al的尖晶石NiFe2O4相;随着NiO含量增加,阳极表面的致密层变得越发不平整。NiFe2O4-xNiO（x=0,5,10,17,25 wt%） composite ceramics were prepared with sintering method under controlled atmosphere and their electrolysis corrosion in aluminum electrolysis at 960 ℃ were examined.Based on the studies of the microstructure and phase composition after sintering,surface morphology and composition after electrolysis,the effects of NiO additive on the sintering properties and electrolysis corrosion of NiFe2O4 ceramics were analyzed.The sintering mechanism and molten salt corrosion behavior were also discussed.The results show that the composite ceramic is composed of NiO and NiFe2O4 phase,and the content of NiO is higher than the theoretical value.The doped NiO results in the decrease of the relative densities of composite ceramics.The dense protective layer,which is thickness of 50～80 μm and consists of NiFe2O4 containing Al element,is formed in the anode surfaces during electrolysis,and they become more uneven with the increase of NiO contents.

关 键 词：铝电解 惰性阳极 铁酸镍 电解腐蚀 

分 类 号：TF821[冶金工程—有色金属冶金]