纳米增韧Φ100 mm圆柱形NiFe₂O₄基惰性阳极的电解腐蚀行为研究

Study on Electrolytic Corrosion Behavior and Mechanism of Nano Toughened Φ100 mm Cylindrical NiFe₂O₄ Based Inert Anode

采用粉末冶金两步烧结法制备纳米增韧Φ100 mm圆柱形NiFe2O4基惰性阳极,通过10 h电解实验研究其电解腐蚀行为与机理。研究结果表明纳米增韧Φ100 mm圆柱形NiFe2O4基惰性阳极高温稳定性好,金属导杆和惰性阳极通过固相烧结扩散连接具备足够的高温强度和导电性能,电解过程中槽电压保持相对稳定。电解10 h后阳极没有发生开裂、肿胀、表面起层等现象,表现出较好的抗热震性能和耐腐蚀性能;产品铝纯度为98.02%,其中杂质主要为Fe、Ni和Cu,耐腐蚀性能需要进一步提升。NiFe2O4纳米粉的添加能够有效地增强阳极材料的晶界结合强度和降低气孔率,降低电解质组成渗入阳极内部几率,从而有效提高NiFe2O4基惰性阳极的耐熔盐腐蚀能力。

Nano toughened Φ100 mm cylindrical NiFe2O4 based inert anodes was prepared by powder me-tallurgy two-step sintering method. The electrolytic corrosion behavior and mechanism of NiFe2O4 based inert anodes were investigated by 10 h electrolysis experiment. The results show that the cell voltage keeps relatively stable, which is attributed to the good high temperature stability of nano toughened cylindrical NiFe2O4 based inert anode as well as the adequate high-temperature strength and conductivity of the solid state sintered connection between metal rod and inert anode. The electrolyzed inert anode has not undergone cracking or swelling, showing a suitable thermal shock resistance and corrosion resistance. The corrosion resistance should be enhanced for the purity of product aluminum was 98.02%, where the main impurities were Fe, Ni and Cu. The enhanced grain boundary bonding strength and decreased porosity, derived from the adding of NiFe2O4 nanopowder, can reduce the probability of electrolyte infiltration into the anode inside. As a result, the corrosion resistance of nano toughened NiFe2O4 based inert anodes has been improved effectively.