Effect of NiO addition on the high-temperature oxidation and corrosion behaviors of Fe–Ni alloy as inert anode material for aluminum electrolysis
- 10 Downloads
A new type of Fe–Ni ceramet inert anode with the NiO contents of 0, 10, 20 and 30 wt% for aluminum electrolysis was prepared by the powder metallurgy process. The effects of NiO addition on the high-temperature oxidation and corrosion behaviors of the ceramet had been investigated by the thermogravimetric analysis and electrolysis, respectively. The results indicated that the pre-existing oxide phase shortened the time for formation of the oxide scale on the sample, which promoted the formation of continuous dense scale with the good adhesion to substrate materials during high-temperature oxidation. Besides, the appearance of NiO at the grain boundary hindered the oxidation of the metal phase, which avoids the peeling phenomenon. As a result, the addition of NiO in the Fe–Ni alloy played an important role in hindering the oxidation process, which greatly improved the anti-oxidant properties. Compared with the alloy anode, additionally, the total impurity content in the melted aluminum electrolyte was 0.28 mass% for 100 h of electrolysis at 20 A. It indicated that the addition of NiO improved the corrosion resistance of Fe–Ni ceramet anode significantly. Therefore, the Fe–Ni ceramet anode may be the promising inert anode materials for the aluminum electrolysis.
This work was supported in part by the financial support of the Key Scientific Research Projects of Higher Education Institutions in Henan Province (19B430013) and the Young Key Teachers Training Program of Henan Province Higher Education Institutions (2018GGJS090).
- 1.Benedyk JC (2001) Status report on inert anode technology for primary aluminum. Light Met Age 59(2):36–37Google Scholar
- 2.Nora D (2001) Inert anodes are knocking at the door of aluminium producers. In: CRU annual meeting, vol 26, LondonGoogle Scholar
- 10.Sadoway DR (1990) A materials systems approach to selection and testing of non-consumable anodes for the Hall cell. Light Met TMS, 403–407Google Scholar
- 18.Lin QQ, Long YP, Dong WZ (2014) Effect of Y2O3 doped on high-temperature oxidation performance of 17Ni/(NiFe2O4–10NiO) cermet. Bull Ceram Soc 33(4):890–894Google Scholar