Research on Properties of Al2O3-Based Cermets Inert Anode

The cermets were prepared for aluminum electrolysis as inert anode. The microstructure of cermets inter anode was dense , the crystal of cermets growth ideally. The electric conductivity was stable and good, had the electric conductivity property of the semiconductor. The conductivity increased with temperature increasing. Electrolysis was conducted 12h at 850℃ in cryolite molten salt(CR=2.0, Al₂O₃ comtent 5.0% ), and the anodic current density was 1.0 A/cm2.The results showed that the cermets inert anode had high anti-oxidation, corrosion resistance and high conductivity. The back electromotive force was 2.45V, the decomposition voltage was 2.18V, the conductivity at 850℃ was 47S/cm, the annual corrosion rate was 23.68 mm/year.