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采用粉末冶金法在3种温度下制备了60Ni40Fe,10Cu50Ni40Fe和65Cu25Ni10Fe3种合金,并分别作为惰性阳极在700℃钾冰晶石低温体系(CR=1.3)中进行5A级的实验室规模铝电解,电解电流密度为0.5A.cm-2,电解时间为8.0h。3种NiFe合金阳极体系电解过程相差明显,不含有Cu的60Ni40Fe合金阳极电解过程槽电压波动较大,原铝的纯度仅为91.23%;65Cu25Ni10Fe合金阳极电解过程中槽电压比较平稳,平均槽电压为3.422V,但是原铝中杂质Cu含量达到4.5%;10Cu50Ni40Fe合金阳极电解过程槽电压比较平稳,平均槽电压为3.829V,原铝的纯度可达99.74%,是3种合金中电解性能最优的阳极。采用XRD,SEM和EDS等手段分析合金阳极电解后表面组成、结构及形貌的变化情况。表明3种NiFe合金阳极表面氧化膜成分相差明显,60Ni40Fe和65Cu25Ni10Fe合金阳极表面分别生成了NiO和Ni0.8Cu0.2O,结构比较疏松。10Cu50Ni40Fe合金阳极表面氧化膜的元素扫描表明各元素为层状分布,在合金基体表面生成了比较致密的Ni1.25Fe1.85O4,Ni1.25Fe1.85O4对合金阳极具有很好的保护作用,抑制了熔盐及氧对合金基体的腐蚀。
60Ni40Fe, 10Cu50Ni40Fe and 65Cu25Ni10Fe3 alloys were prepared by powder metallurgy method and used as inert anode for 5A scale laboratory scale aluminum electrolysis at 700 ℃ for cryolite cryogenic system (CR = 1.3). The electrolysis current The density is 0.5A.cm-2, the electrolysis time is 8.0h. The electrolysis process of the three kinds of NiFe alloy anode system was obviously different. The voltage of the anode in 60Ni40Fe alloy anode without electrolytic copper had large fluctuation and the purity of primary aluminum was only 91.23%. The cell voltage of 65Cu25Ni10Fe alloy was steady and the average cell voltage was 3.422V, but the content of Cu in the primary aluminum reached 4.5%. The cell voltage of 10Cu50Ni40Fe alloy anode was relatively steady, the average cell voltage was 3.829V, the purity of primary aluminum was up to 99.74%, which was the best of the three alloys anode. XRD, SEM and EDS were used to analyze the changes of surface composition, structure and morphology after anodization. The results show that the composition of the oxide films on the surface of the three kinds of NiFe alloy anodes are obviously different. NiO and Ni0.8Cu0.2O are formed on the surface of 60Ni40Fe and 65Cu25Ni10Fe alloy, respectively. Elemental scanning of the oxide film on the surface of 10Cu50Ni40Fe alloy showed that all the elements were layered and formed relatively dense Ni1.25Fe1.85O4 on the surface of the alloy matrix. Ni1.25Fe1.85O4 had a good protective effect on the alloy anode and inhibited the melting Salt and oxygen corrosion of the alloy matrix.