(中南大學(xué) 粉末冶金國(guó)家重點(diǎn)實(shí)驗(yàn)室，長(zhǎng)沙 410083)
摘 要: 采用氣氛燒結(jié)方法制備NiFe2O4基金屬陶瓷材料，并進(jìn)行960 ℃的鋁電解腐蝕實(shí)驗(yàn)。通過分析燒結(jié)體的顯微結(jié)構(gòu)和物相組成、電解試樣的表層形貌與成分以及電解質(zhì)和陰極鋁的雜質(zhì)含量等，研究BaO、Yb2O3和CoO的添加以及金屬相的組成對(duì)NiFe2O4基金屬陶瓷燒結(jié)性能的影響；表征了該金屬陶瓷強(qiáng)化燒結(jié)體作為鋁電解惰性陽極的電解腐蝕性能；并對(duì)材料強(qiáng)化燒結(jié)機(jī)制和熔鹽腐蝕行為進(jìn)行探討。結(jié)果表明：燒結(jié)過程中，BaO和Yb2O3與該金屬陶瓷中的陶瓷相反應(yīng)生成新的物相，CoO與陶瓷相形成固溶體，并加快燒結(jié)致密化進(jìn)程；以Cu-Ni取代純Cu和純Ni作為金屬陶瓷的金屬相，可提高材料的相對(duì)密度；NiFe2O4基金屬陶瓷的高致密度可抑制電解過程中金屬相的流失和陶瓷相的腐蝕，陽極表層也轉(zhuǎn)變?yōu)橹旅艿腘iFe2O4相。
關(guān)鍵字: 惰性陽極；鋁電解；金屬陶瓷；NiFe2O4；電解腐蝕
nickel ferrite based cermets
（State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China）
Abstract:NiFe2O4 based cermets were prepared by sintering method under controlled atmosphere, and their electrolysis corrosion in aluminum electrolysis at 960 ℃ was examined. Based on the studies of the microstructure and phase composition after sintering, surface morphology and composition after electrolysis, impurity content in electrolyte and cathode aluminum, the effects of BaO, Yb2O3 and CoO additive and metal composition on the sintering properties of NiFe2O4 based cermets were analyzed. The electrolysis corrosion property of highly sintered cermets as inert anode was characterized. The enhanced sintering mechanism and molten salt corrosion behavior were also discussed. The results show that the doped BaO, Yb2O3 and CoO react with the ceramic matrix, and then accelerate the process of sintering densification. The substituting of pure Cu and pure Ni by Cu-Ni as metal phase of cermets can increase the relative density of NiFe2O4 based cermets. The high relative density of NiFe2O4 based cermets is benefit to inhibit metal loss and ceramic-phase corrosion, and the anode surface will change to NiFe2O4 dense layer.
Key words: inert anode; aluminum electrolysis; cermets; NiFe2O4; electrolysis corrosion
